997.1 C2S - Another IDLE mystery
10-31-2012, 12:45 PM
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997.1 C2S - Another IDLE mystery
Hi everyone,
I'm trying to help a friend (who doesn't speak english) to fix his IDLE problems on a 997.1 C2S. I will try to describe to the best what's going on :
- He installed cat bypass and GT3 82mm TB + IPD 82mm plenum on a fine working car then he noticed a lack of torque in the low/middle which I know is normal due to the lack of backpressure. A couple of days later, he noticed that his car was running OK for 10-15 min (when cold) and then once the engine at its operating temperature he had problems ONLY with IDLE ex. at a red light his IDLE decreasing slightly until engine starving...but it was not every time at IDLE. Then, a couple of days later, he had a CEL which was probably caused by the cat bypass (according to me) so he returned to stock cats but changed the mufflers and headers to Fabspeed ones...then Resested the DME...same problem : engine starving from time to time at IDLE only when hot.
Later, he reprogramed the DME with Softronic : same problem remains. He replaced the MAF sensor because we thought that it was the problem (because the IDLE was OK with MAF disconnected but noticed a loss of torque and hesitation). After MAF replaced, the problem is...still the same.
We checked for air leaks after the MAF sensor and everything was correctly tightened - TB/Plenum gasket in place so I'm pretty sure it's also not an air leak. BUT I noticed that in the plenum, there was a lot of liquid (unburned fuel I guess?). To me it seems very suspicious because I worked a couple of times in this area on my car and I don't remember having seen that!
So what does it mean? Engine is running too rich? Too much fuel from the injectors for the amount of air readed by the MAF?
If the MAF sensor in OK (new) and there is no intake leaks, what can be the cause? Now he has no CEL. O2 sensors? OK, but why is the engine IDLing OK with the MAF sensor disconnected?
I thought that he may try to put spacers on the O2 post cat sensors to fool them and see if the problem remains (to avoid buying new O2 sensors for nothing)
I must admit that I don't know what to think and I would greatly appreciate any help
Thanks in advance
I'm trying to help a friend (who doesn't speak english) to fix his IDLE problems on a 997.1 C2S. I will try to describe to the best what's going on :
- He installed cat bypass and GT3 82mm TB + IPD 82mm plenum on a fine working car then he noticed a lack of torque in the low/middle which I know is normal due to the lack of backpressure. A couple of days later, he noticed that his car was running OK for 10-15 min (when cold) and then once the engine at its operating temperature he had problems ONLY with IDLE ex. at a red light his IDLE decreasing slightly until engine starving...but it was not every time at IDLE. Then, a couple of days later, he had a CEL which was probably caused by the cat bypass (according to me) so he returned to stock cats but changed the mufflers and headers to Fabspeed ones...then Resested the DME...same problem : engine starving from time to time at IDLE only when hot.
Later, he reprogramed the DME with Softronic : same problem remains. He replaced the MAF sensor because we thought that it was the problem (because the IDLE was OK with MAF disconnected but noticed a loss of torque and hesitation). After MAF replaced, the problem is...still the same.
We checked for air leaks after the MAF sensor and everything was correctly tightened - TB/Plenum gasket in place so I'm pretty sure it's also not an air leak. BUT I noticed that in the plenum, there was a lot of liquid (unburned fuel I guess?). To me it seems very suspicious because I worked a couple of times in this area on my car and I don't remember having seen that!
So what does it mean? Engine is running too rich? Too much fuel from the injectors for the amount of air readed by the MAF?
If the MAF sensor in OK (new) and there is no intake leaks, what can be the cause? Now he has no CEL. O2 sensors? OK, but why is the engine IDLing OK with the MAF sensor disconnected?
I thought that he may try to put spacers on the O2 post cat sensors to fool them and see if the problem remains (to avoid buying new O2 sensors for nothing)
I must admit that I don't know what to think and I would greatly appreciate any help
Thanks in advance
10-31-2012, 02:31 PM
#2
he is throwing too many variables into the mix and not isolating the problem.
I will go 100% stock: plenum, TB and exhaust. see what happens. if ok, then do the Plenum+TB. see what happens. if ok, do the mufflers and would leave the headers and cats for last.
The unburned fuel at the plenum is actually brought by the vacuum/vapor lines from the gas tank/AOS, that's normal...
I will go 100% stock: plenum, TB and exhaust. see what happens. if ok, then do the Plenum+TB. see what happens. if ok, do the mufflers and would leave the headers and cats for last.
The unburned fuel at the plenum is actually brought by the vacuum/vapor lines from the gas tank/AOS, that's normal...
10-31-2012, 02:37 PM
#3
Drifting
Does he have a Durametric diag tool and what does it indicate? You can also use it to run a self test of all systems. One guess w/o further info would be an air leak somewhere especially as the engine heats up. Does he have a smoke generator to test for leaks? What method was used to test for leaks? Suspect would be the rubber hoses connections between the intake manifolds and the Plenum... these are tricky to align. Is he using a dry air filter or an oiled one. It doesn't take much to foil up the MAF. Remember to use very little oil after cleaning an oiled filter and let it sit over night to saturate/distribute properly throughout the filter. It's very common to over oil those types of filters and you will foul the MAF and see oil inside the intake manifold as a result. Try to remove the MAF and clean with some MAF cleaner spray. Don't touch the MAF wiring either unless you're well grounded JIC... think anti-static strap just to be safe.
Check with Softronics as well and make sure the re-program took. When uploading it's essential with most ECU remap programs that you remove all firewalls and anti-virus scan programs from the PC/notebook before doing so... otherwise it may not upload properly/fully and you will see CEL's intermittently after driving. Also make sure that he had a secure connection when he connects the cable to the ODBC port. These were symptoms I dealt with and resolved with my own FVD remap program after some experimentation and excellent tech support from FVD.
You may have multiple issues here so troubleshoot all items and back track... for example, an easy back track would be to just upload the original ECU map to eliminate Softronic as a potential cause. Work backwards removing one item/mod at a time until you have the system completely stock again if necessary... for example, you may have two fouled/bad MAF's (it happens especially if you're friend has never handled one before) and a stock setup would help to root cause/illustrate root cause. This is why I like to only modify one item at a time on my cars and I'll drive them for a few weeks between mods to isolate any idiosyncrasies with any particular add on. BTW, I just went thru a similar list of mods on my '08 C2S in the following order:
1. Full FVD 70mm vs. 62mm stock exhaust (200 cell cats, long race pipe headers, muffler, and tips)... drove for two months w/o CEL then
2. FVD remap... ditto and learned how to properly upload to the ECU
3. IPD Competition TB and Plenum... recently executed mod and too early to tell if it's stable yet but no issues so far.
GL and share the outcome with the group when your friend makes further progress. Very nice of you to help him by writing this up.
Check with Softronics as well and make sure the re-program took. When uploading it's essential with most ECU remap programs that you remove all firewalls and anti-virus scan programs from the PC/notebook before doing so... otherwise it may not upload properly/fully and you will see CEL's intermittently after driving. Also make sure that he had a secure connection when he connects the cable to the ODBC port. These were symptoms I dealt with and resolved with my own FVD remap program after some experimentation and excellent tech support from FVD.
You may have multiple issues here so troubleshoot all items and back track... for example, an easy back track would be to just upload the original ECU map to eliminate Softronic as a potential cause. Work backwards removing one item/mod at a time until you have the system completely stock again if necessary... for example, you may have two fouled/bad MAF's (it happens especially if you're friend has never handled one before) and a stock setup would help to root cause/illustrate root cause. This is why I like to only modify one item at a time on my cars and I'll drive them for a few weeks between mods to isolate any idiosyncrasies with any particular add on. BTW, I just went thru a similar list of mods on my '08 C2S in the following order:
1. Full FVD 70mm vs. 62mm stock exhaust (200 cell cats, long race pipe headers, muffler, and tips)... drove for two months w/o CEL then
2. FVD remap... ditto and learned how to properly upload to the ECU
3. IPD Competition TB and Plenum... recently executed mod and too early to tell if it's stable yet but no issues so far.
GL and share the outcome with the group when your friend makes further progress. Very nice of you to help him by writing this up.
11-01-2012, 11:53 AM
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Joel, I absolutely do agree with you...too much variables too quickly at once. Now yeah, let's find the problem 
USMC, no he doesn't but he got a Durametric cable when he bought his Softronic tune. I guess this cable and Durametric software he dowloaded from the internet are not enough in order to read the error codes? (never used on mine aswell)
No we didn't used smoke generator - just bolted everything off, checked there was no cracks or holes in the rubber hoses and bolted everything back again - also checked the o-ring gasket between TB and plenum.. I know it's not a very scientific approach but it was all we were able to do at the time...
I installed his MAF and uploaded his Softronic and unless the new MAF is wrong from factory, I'm absolutely sure I was very attentive to not touch with anything the MAF sensor. Same thing with Softronic - followed very carefully the instructions and I'm sure the upload was OK
Oh, and he is using a dry dual cone air intake.
Today morning we reseted the DME (first time after the Softronic upgrade) and he was very pleased with how the car ran - very smootly - IDLE perfect for almost one hour of driving - THEN - the car cooled down for 20 min - after starting again - IDLE OK for 2-3 sec then engine starving. Definitely curious story.
I obviously may be wrong but I think that at this point if it's not the MAF reading which is in cause, it may be the O2 sensors (once warmed up).
Can You tell me even if with faulty O2 sensor(s) disconecting the MAF sensor would bring the car back to normal like we see it on his one? Another question - assuming it's the O2 sensor(s), would putting spacers (like those used by guys with catbypass) on the post cats sensors and connecting the MAF back again cause a loss of power/torque? Because he says that when he disconects the MAF he feels the car a bit lazy and different - in other words, does the DME/MAF/O2 sensors "algorithmic loop" must be intact in order to have optimum performance or is it possible to fool the O2 sensors without experimenting any performance loss?
Thank you for your help guys
USMC, no he doesn't but he got a Durametric cable when he bought his Softronic tune. I guess this cable and Durametric software he dowloaded from the internet are not enough in order to read the error codes? (never used on mine aswell)
No we didn't used smoke generator - just bolted everything off, checked there was no cracks or holes in the rubber hoses and bolted everything back again - also checked the o-ring gasket between TB and plenum.. I know it's not a very scientific approach but it was all we were able to do at the time...
I installed his MAF and uploaded his Softronic and unless the new MAF is wrong from factory, I'm absolutely sure I was very attentive to not touch with anything the MAF sensor. Same thing with Softronic - followed very carefully the instructions and I'm sure the upload was OK
Oh, and he is using a dry dual cone air intake.
Today morning we reseted the DME (first time after the Softronic upgrade) and he was very pleased with how the car ran - very smootly - IDLE perfect for almost one hour of driving - THEN - the car cooled down for 20 min - after starting again - IDLE OK for 2-3 sec then engine starving. Definitely curious story.
I obviously may be wrong but I think that at this point if it's not the MAF reading which is in cause, it may be the O2 sensors (once warmed up).
Can You tell me even if with faulty O2 sensor(s) disconecting the MAF sensor would bring the car back to normal like we see it on his one? Another question - assuming it's the O2 sensor(s), would putting spacers (like those used by guys with catbypass) on the post cats sensors and connecting the MAF back again cause a loss of power/torque? Because he says that when he disconects the MAF he feels the car a bit lazy and different - in other words, does the DME/MAF/O2 sensors "algorithmic loop" must be intact in order to have optimum performance or is it possible to fool the O2 sensors without experimenting any performance loss?
Thank you for your help guys
11-01-2012, 01:43 PM
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Yes I found that we can use his cable after instaling Durametric 6 (thought would need some activation codes or so).
Here is what we found :
-P 1095 AIR MASS HFM ahead of throttle valve - implausible
-P 1090 HFM : electrical fault
-P 0112 : Intake - air temperature sensor : electrical fault
So yep, it seems to clearly come from the MAF sensor. I guess that the electrical faults come from disconecting the MAF? What does this mean to You?
His new MAF sensor would be in cause ? I think it is more probable that there is something wrong with the filters. I will tell him to clean his MAF and replace filters..
Here is what we found :
-P 1095 AIR MASS HFM ahead of throttle valve - implausible
-P 1090 HFM : electrical fault
-P 0112 : Intake - air temperature sensor : electrical fault
So yep, it seems to clearly come from the MAF sensor. I guess that the electrical faults come from disconecting the MAF? What does this mean to You?
His new MAF sensor would be in cause ? I think it is more probable that there is something wrong with the filters. I will tell him to clean his MAF and replace filters..
Last edited by 997C2S9ff; 11-01-2012 at 02:00 PM.
11-01-2012, 02:19 PM
#6
Drifting
OK, a lot going on here but I'll comment where I have some shared DIY knowledge:
"USMC, no he doesn't but he got a Durametric cable when he bought his Softronic tune. I guess this cable and Durametric software he dowloaded from the internet are not enough in order to read the error codes? (never used on mine aswell)"
The cables all look similar. My FVD cable looks just like the Durametric cable as well but I was advised by FVD that internally they are different so the DM software will not work a 100% unless I actually get a true DM cable. Check with Softronics to see if this is the case as well with your cable but it does sounds like your cable is getting some readings here... so I wonder if it is fully supported by DM. They can be a great source for trouble supporting as well. Your error codes seem to be pointing towards the MAF issue so again an air leak or bad MAF are the likely suspects. Don't rule out the MAF wiring as well. Try to spray some contact cleaner on the MAF connector/contact points. If you're car is similar to you're friend's Carrera then swapping MAF's back and forth is another troubleshooting option, however, it could potentially transfer his issues to your car. For example, swapping components from one PC to anther(know good donor PC) is a common troubleshooting practice but there are those rare occasions where a bad component will affect/fry the other good donor system components. Can be a convenient and inexpensive troubleshooting method on PC's but with a Porsche it's something to be careful off for obvious reasons. So here's the MAF troubleshooting option I highly recommend you try once you get the DM cable working properly... http://www.6speedonline.com/forums/9...urametric.html
"I installed his MAF and uploaded his Softronic and unless the new MAF is wrong from factory, I'm absolutely sure I was very attentive to not touch with anything the MAF sensor. Same thing with Softronic - followed very carefully the instructions and I'm sure the upload was OK
Oh, and he is using a dry dual cone air intake." This is all good. BTW, did you try running the car with the original ECU mapping to eliminate the Softronic tune/remap as a potential root cause?
"USMC, no he doesn't but he got a Durametric cable when he bought his Softronic tune. I guess this cable and Durametric software he dowloaded from the internet are not enough in order to read the error codes? (never used on mine aswell)"
The cables all look similar. My FVD cable looks just like the Durametric cable as well but I was advised by FVD that internally they are different so the DM software will not work a 100% unless I actually get a true DM cable. Check with Softronics to see if this is the case as well with your cable but it does sounds like your cable is getting some readings here... so I wonder if it is fully supported by DM. They can be a great source for trouble supporting as well. Your error codes seem to be pointing towards the MAF issue so again an air leak or bad MAF are the likely suspects. Don't rule out the MAF wiring as well. Try to spray some contact cleaner on the MAF connector/contact points. If you're car is similar to you're friend's Carrera then swapping MAF's back and forth is another troubleshooting option, however, it could potentially transfer his issues to your car. For example, swapping components from one PC to anther(know good donor PC) is a common troubleshooting practice but there are those rare occasions where a bad component will affect/fry the other good donor system components. Can be a convenient and inexpensive troubleshooting method on PC's but with a Porsche it's something to be careful off for obvious reasons. So here's the MAF troubleshooting option I highly recommend you try once you get the DM cable working properly... http://www.6speedonline.com/forums/9...urametric.html
"I installed his MAF and uploaded his Softronic and unless the new MAF is wrong from factory, I'm absolutely sure I was very attentive to not touch with anything the MAF sensor. Same thing with Softronic - followed very carefully the instructions and I'm sure the upload was OK
Oh, and he is using a dry dual cone air intake." This is all good. BTW, did you try running the car with the original ECU mapping to eliminate the Softronic tune/remap as a potential root cause?
11-01-2012, 04:01 PM
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Yes, it was exactly the same before and after the Softronic - the only difference is that the car runs better with MAF connected and Softronic
I told him to buy MAF cleaner and electrical cleaner to start with. If it doesn't works, we will log the maf data according to the link you sent!
I think that I didn't wrote clearny enough (sorry for my english) The DM cable he has works fine. It's just that until today, we thought that we need some activation code or a durametric CD or so in order to make it work. A quick research on the net showed that all we needed to do is...download and intall the Durametric 6 software
I will keep the post updated!
I told him to buy MAF cleaner and electrical cleaner to start with. If it doesn't works, we will log the maf data according to the link you sent!
I think that I didn't wrote clearny enough (sorry for my english) The DM cable he has works fine. It's just that until today, we thought that we need some activation code or a durametric CD or so in order to make it work. A quick research on the net showed that all we needed to do is...download and intall the Durametric 6 software
I will keep the post updated!
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11-06-2012, 04:22 PM
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Today we cleaned the new MAF sensor two times with MAF cleaner - let it dry...reconnected. First start up IDLE ok for a minute (but a little low around 500rpm). 5 min later started it again and idle became crazy from 150 (almost starving) to 800-900 rpm then starved after a few cycles.
I just don't understand what else can be linked to these MAF errors... It's driving us crazy.
Air filters? Honestly I doubt it could cause a such strong and crazy effect on the MAF/IDLE (and the filters are 4-5 months old). I may be wrong.. Or the rubber between the air intake and throttle body (used the one that came with the air intake, not the one from IPD because it was designed for the stock intake box)
Maybe we should try to retrofit the stock air intake box and see how it behaves...?
If anyone has an idea, we would really appreciate any suggestion.
Thanks
I just don't understand what else can be linked to these MAF errors... It's driving us crazy.
Air filters? Honestly I doubt it could cause a such strong and crazy effect on the MAF/IDLE (and the filters are 4-5 months old). I may be wrong.. Or the rubber between the air intake and throttle body (used the one that came with the air intake, not the one from IPD because it was designed for the stock intake box)
Maybe we should try to retrofit the stock air intake box and see how it behaves...?
If anyone has an idea, we would really appreciate any suggestion.
Thanks
11-10-2012, 02:39 PM
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Ok 
Good news up there.
Today we bolted the stock air filter box with the BMC filter and then...miracle.
IDLE is perfect. Started the car a couple of times and did some runs and everything works fine. I'm really surprised on the filter box being capable of such consequences on the IDLE.. Anyway, happy end this time
For those interesed in the filter box he bought (and maybe to avoid similar problems to other members) it's this one (Y shape carbon fiber dual cone one) : http://www.porscheshop.co.uk/acatalo...sche_cars.html
Thanks for the help!
Good news up there.Today we bolted the stock air filter box with the BMC filter and then...miracle.
IDLE is perfect. Started the car a couple of times and did some runs and everything works fine. I'm really surprised on the filter box being capable of such consequences on the IDLE.. Anyway, happy end this time For those interesed in the filter box he bought (and maybe to avoid similar problems to other members) it's this one (Y shape carbon fiber dual cone one) : http://www.porscheshop.co.uk/acatalo...sche_cars.html
Thanks for the help!
11-10-2012, 03:05 PM
#10
Ok Good news up there.
Today we bolted the stock air filter box with the BMC filter and then...miracle.IDLE is perfect. Started the car a couple of times and did some runs and everything works fine. I'm really surprised on the filter box being capable of such consequences on the IDLE.. Anyway, happy end this time
For those interesed in the filter box he bought (and maybe to avoid similar problems to other members) it's this one (Y shape carbon fiber dual cone one) : http://www.porscheshop.co.uk/acatalo...sche_cars.html
Thanks for the help!
Good news up there.Today we bolted the stock air filter box with the BMC filter and then...miracle.
IDLE is perfect. Started the car a couple of times and did some runs and everything works fine. I'm really surprised on the filter box being capable of such consequences on the IDLE.. Anyway, happy end this time For those interesed in the filter box he bought (and maybe to avoid similar problems to other members) it's this one (Y shape carbon fiber dual cone one) : http://www.porscheshop.co.uk/acatalo...sche_cars.html
Thanks for the help!
11-11-2012, 01:09 PM
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Holy F***!! The problem is still there. I will explain what happened.
After the retrofit to the stock air filter box, the car ran fine for a while, then suddenly today it came back! So it clearly had an influence on this IDLE mystery...
Important thing : today we noticed that there was some kind of "click" noise on the right side of the car, close the throttle body area - like a valve or something - and EACH time it "opens" or "closes" the IDLE is fine, then on the next "click" it varies between 400-900rpm...then after the next ones comes back to smooth IDLE and so on and so on...every approx. 10sec.
We have no idea what it can be but it is absolutely linked to the variation of the IDLE. We also noticed that while doing this, when he hits the throtle, the IDLE comes back to normal for maybe 5 sec. It looks like there is a difference between the amount of air readed by the MAF and received by the engine..But what? The reading would be too low according to this? Or the opposite?
I also read somewhere that this clicking can be the throttle body adapting opening for the IDLE...but what does it mean? Why is it fluctuating every 10 sec? It's a brand new Porsche part..
We also tried some special sray (used on the cars air filter during winter to help them to start). Sprayed it on the plenum/manifold rubber but there wa no reaction. I know it's not as efficient method as smoke...we just tried what we could.
We would appreciate any help to solve this sick mystery
After the retrofit to the stock air filter box, the car ran fine for a while, then suddenly today it came back! So it clearly had an influence on this IDLE mystery...
Important thing : today we noticed that there was some kind of "click" noise on the right side of the car, close the throttle body area - like a valve or something - and EACH time it "opens" or "closes" the IDLE is fine, then on the next "click" it varies between 400-900rpm...then after the next ones comes back to smooth IDLE and so on and so on...every approx. 10sec.
We have no idea what it can be but it is absolutely linked to the variation of the IDLE. We also noticed that while doing this, when he hits the throtle, the IDLE comes back to normal for maybe 5 sec. It looks like there is a difference between the amount of air readed by the MAF and received by the engine..But what? The reading would be too low according to this? Or the opposite?
I also read somewhere that this clicking can be the throttle body adapting opening for the IDLE...but what does it mean? Why is it fluctuating every 10 sec? It's a brand new Porsche part..
We also tried some special sray (used on the cars air filter during winter to help them to start). Sprayed it on the plenum/manifold rubber but there wa no reaction. I know it's not as efficient method as smoke...we just tried what we could.
We would appreciate any help to solve this sick mystery
Last edited by 997C2S9ff; 11-11-2012 at 03:18 PM.
06-29-2016, 07:15 PM
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Holy F***!! The problem is still there. I will explain what happened.
After the retrofit to the stock air filter box, the car ran fine for a while, then suddenly today it came back! So it clearly had an influence on this IDLE mystery...
Important thing : today we noticed that there was some kind of "click" noise on the right side of the car, close the throttle body area - like a valve or something - and EACH time it "opens" or "closes" the IDLE is fine, then on the next "click" it varies between 400-900rpm...then after the next ones comes back to smooth IDLE and so on and so on...every approx. 10sec.
We have no idea what it can be but it is absolutely linked to the variation of the IDLE. We also noticed that while doing this, when he hits the throtle, the IDLE comes back to normal for maybe 5 sec. It looks like there is a difference between the amount of air readed by the MAF and received by the engine..But what? The reading would be too low according to this? Or the opposite?
I also read somewhere that this clicking can be the throttle body adapting opening for the IDLE...but what does it mean? Why is it fluctuating every 10 sec? It's a brand new Porsche part..
We also tried some special sray (used on the cars air filter during winter to help them to start). Sprayed it on the plenum/manifold rubber but there wa no reaction. I know it's not as efficient method as smoke...we just tried what we could.
We would appreciate any help to solve this sick mystery
After the retrofit to the stock air filter box, the car ran fine for a while, then suddenly today it came back! So it clearly had an influence on this IDLE mystery...
Important thing : today we noticed that there was some kind of "click" noise on the right side of the car, close the throttle body area - like a valve or something - and EACH time it "opens" or "closes" the IDLE is fine, then on the next "click" it varies between 400-900rpm...then after the next ones comes back to smooth IDLE and so on and so on...every approx. 10sec.
We have no idea what it can be but it is absolutely linked to the variation of the IDLE. We also noticed that while doing this, when he hits the throtle, the IDLE comes back to normal for maybe 5 sec. It looks like there is a difference between the amount of air readed by the MAF and received by the engine..But what? The reading would be too low according to this? Or the opposite?
I also read somewhere that this clicking can be the throttle body adapting opening for the IDLE...but what does it mean? Why is it fluctuating every 10 sec? It's a brand new Porsche part..
We also tried some special sray (used on the cars air filter during winter to help them to start). Sprayed it on the plenum/manifold rubber but there wa no reaction. I know it's not as efficient method as smoke...we just tried what we could.
We would appreciate any help to solve this sick mystery
07-04-2016, 01:56 AM
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Possible faulty MAF sensor
I had a similar problem as the OP. Even after fixing a couple of vacuum leaks the CEL still re-appeared, finally, I replaced my MAF the other day and P095 never came back. I was clearing the CEL every day for a full week. Have since driven it 100 plus miles in 2 days and my car drives much better. No more speradic flat spots as I ride up the RPMs. The only annoyance now is the engine RPM's fluctuating 45 seconds after i start the car but goes away by the time I pull out of my driveway. I commented about this, looking for answers in another post and wonder if it's simply the car adapting. I hope the ECU learns.....and learns quickly.
