Misfire
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From: Belgium
Originally Posted by GabiOsz
It could possibly be the O2 sensor on the catalitic converter or the MAF sensor. The O2 sensor is a fair bit cheaper than the MAF, and I believe that some have had success with cleaning the MAF sensor with PCB cleaner. Incidentally what air filter are you using?
If you want to test the distributer belt, with the engine off, unplug the wire from the ignition coil to the primary distributer, if the engine starts then the belt is in tact.
If you want to test the distributer belt, with the engine off, unplug the wire from the ignition coil to the primary distributer, if the engine starts then the belt is in tact.
Are the car sensos accessible without taking the engine apart ?
If I drive the car at high speed for a while the problem seems to go away. It started again in stop and go traffic. It was pissing down with rain when it reoccurred yesterday. Running rough and billowing smoke. Went away when I got on the motorway, but fuel consumption was scary.
Peter R.
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From: Belgium
Originally Posted by JasonAndreas
I don't think your problem is CHT related but you wanted to know what the current day equivalent was of the cold start injector. The DME control unit uses the temperature reading from the CHT to increase the opening time (i.e. add extra fuel) of all the injectors.
Peter R.
Burning Brakes
Joined: Mar 2004
Posts: 993
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From: United Kingdom
Peter, I have ditched the K & N filter all together. An even slightly over oiled filter causes the oil to get sucked into the intake and it can sit on the MAF creating an oily film on the "hot wire" sensor which reduces it's effectivness and causes these problems.
The MAF sensor is easy to get at, if you take off the air box (back and front) you will see a wire coming out of the next part of the intake, thats your MAF sensor. You should really unplug the wire and remove the section of the intake with the sensor inside the get good access, then clean it with PCB cleaner, being careful not to leave a residue. Replace the whole assembly and air box, preferably with a OEM paper filter (believe me these are good enough for our engines and you'll avoid these problems). Now take the car for a good drive, and remember the ECU can take a little time to adjust to changes.
Let me know how you get on.
The MAF sensor is easy to get at, if you take off the air box (back and front) you will see a wire coming out of the next part of the intake, thats your MAF sensor. You should really unplug the wire and remove the section of the intake with the sensor inside the get good access, then clean it with PCB cleaner, being careful not to leave a residue. Replace the whole assembly and air box, preferably with a OEM paper filter (believe me these are good enough for our engines and you'll avoid these problems). Now take the car for a good drive, and remember the ECU can take a little time to adjust to changes.
Let me know how you get on.
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From: Belgium
Originally Posted by FotoVeloce
OK. I know this is sort of 'out there' but did you fill UP the tank with fuel.. like all the way? Sure.. why not, right?
OK. so I bought thist 964. The next day it ran like complete trash when you put more than 3/4 of a tank of fuel in. Sometimes, smoke, sputter, stall, lose power.. not fun.. especially if you forget to tell the guy to STOP at 3/4 when he's filling it up.
To make matters worse.. mine got so bad fuel was dripping out of the eval canister in front of the left-rear wheel!
Turned out that is was a failed check valve on top of the fuel tanks expansion chamber. Replaced that and viola.. all is right with the world.
Just tossing that out there.... I was
when I thought the 964 had gone TU 1 day after purchase..
Good luck, and congrats on dumping the 2-wheeler!
OK. so I bought thist 964. The next day it ran like complete trash when you put more than 3/4 of a tank of fuel in. Sometimes, smoke, sputter, stall, lose power.. not fun.. especially if you forget to tell the guy to STOP at 3/4 when he's filling it up.
To make matters worse.. mine got so bad fuel was dripping out of the eval canister in front of the left-rear wheel!
Turned out that is was a failed check valve on top of the fuel tanks expansion chamber. Replaced that and viola.. all is right with the world.
Just tossing that out there.... I was
when I thought the 964 had gone TU 1 day after purchase.. Good luck, and congrats on dumping the 2-wheeler!
Peter R.
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From: Belgium
Originally Posted by GabiOsz
Peter, I have ditched the K & N filter all together. An even slightly over oiled filter causes the oil to get sucked into the intake and it can sit on the MAF creating an oily film on the "hot wire" sensor which reduces it's effectivness and causes these problems.
The MAF sensor is easy to get at, if you take off the air box (back and front) you will see a wire coming out of the next part of the intake, thats your MAF sensor. You should really unplug the wire and remove the section of the intake with the sensor inside the get good access, then clean it with PCB cleaner, being careful not to leave a residue. Replace the whole assembly and air box, preferably with a OEM paper filter (believe me these are good enough for our engines and you'll avoid these problems). Now take the car for a good drive, and remember the ECU can take a little time to adjust to changes.
Let me know how you get on.
The MAF sensor is easy to get at, if you take off the air box (back and front) you will see a wire coming out of the next part of the intake, thats your MAF sensor. You should really unplug the wire and remove the section of the intake with the sensor inside the get good access, then clean it with PCB cleaner, being careful not to leave a residue. Replace the whole assembly and air box, preferably with a OEM paper filter (believe me these are good enough for our engines and you'll avoid these problems). Now take the car for a good drive, and remember the ECU can take a little time to adjust to changes.
Let me know how you get on.
Peter R.
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From: Belgium
So I took out the MAF yesterday evenig, cleaned it with PCB cleaner (very carefully), and put it back.
I've got the impression it starts smoking even faster than before, so I guess I'm on the right track. I'm trying to locate a 'loaner' MAF in the neighborhood to make absolutely sure. Decided to pass on taking her out for a spin.
What's the sensor that is located abbout 2" to the left of the MAF ?
Good new is I've learnt a lot about taking apart my M05, and it's workings lately. So it's not all bad news !
Peter R.
Edit : I tried the starting-on-one-dizzy lark, and it starts just fine, so the belt is still in one piece. I also disconnected the cold running solenoid, and the engine stalls immediately, so that's ok as well.
I'll check the caps and rotors tonight. But since it overfuels like there's no tomorrow, I have the impression it MUST be the MAF gizmo
I've got the impression it starts smoking even faster than before, so I guess I'm on the right track. I'm trying to locate a 'loaner' MAF in the neighborhood to make absolutely sure. Decided to pass on taking her out for a spin.
What's the sensor that is located abbout 2" to the left of the MAF ?
Good new is I've learnt a lot about taking apart my M05, and it's workings lately. So it's not all bad news !
Peter R.
Edit : I tried the starting-on-one-dizzy lark, and it starts just fine, so the belt is still in one piece. I also disconnected the cold running solenoid, and the engine stalls immediately, so that's ok as well.
I'll check the caps and rotors tonight. But since it overfuels like there's no tomorrow, I have the impression it MUST be the MAF gizmo
Last edited by Peter R.; Feb 14, 2007 at 05:34 AM.
Three Wheelin'
Joined: Dec 2004
Posts: 1,779
Likes: 1
From: Halifax, Nova Scotia , Canada
Gizzmo to the left ( 2 pin plug ? ) is the air temperature sensor .
Have you considered getting an interface for Dougs excellent software ?
You could then look at the values the the DME is "seeing" and identify the problem much more quickly ! Probably less expensive than all the parts you could change !!
Geoff
Have you considered getting an interface for Dougs excellent software ?
You could then look at the values the the DME is "seeing" and identify the problem much more quickly ! Probably less expensive than all the parts you could change !!
Geoff
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Three Wheelin'
Joined: Dec 2004
Posts: 1,779
Likes: 1
From: Halifax, Nova Scotia , Canada
Peter,
Just do a search for "OBD software" on this forum. There is moutains of it !
Bottom line is that a simple serial interface is needed together with the top rate Doug Boyce software .
Armed with that combo , actual values can be read which will help dramatically with fault finding.
Good luck
Geoff
Just do a search for "OBD software" on this forum. There is moutains of it !
Bottom line is that a simple serial interface is needed together with the top rate Doug Boyce software .
Armed with that combo , actual values can be read which will help dramatically with fault finding.
Good luck
Geoff
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From: Belgium
Unfortunately, my gizmo is OBDII only, and refuses to communicate with my p-car.
I'm getting mighty depressed with all this smoking lark.
Next question : when I start her up stone cold, and I pull the plug on that temp sensor about 2" to the left of the maf, absolutely nothing happens to the running of the engine. Is this normal ? OTOH, if I pull the plug on the ISV, it stutters a bit and dies. This DOES seem normal.
Peter R.
I'm getting mighty depressed with all this smoking lark.
Next question : when I start her up stone cold, and I pull the plug on that temp sensor about 2" to the left of the maf, absolutely nothing happens to the running of the engine. Is this normal ? OTOH, if I pull the plug on the ISV, it stutters a bit and dies. This DOES seem normal.
Peter R.
Three Wheelin'
Joined: Dec 2004
Posts: 1,779
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From: Halifax, Nova Scotia , Canada
Peter,
Air temp compensation is very small . The head temp is a major element in fuelling level.
The head sensor is screwed into the front of number 3 head. The sensor connector is the white plug in the row on the LH side of the motor . If you pull the plug you will see it has two pins in a three pin housing.
A multimeter across the two pins will give an idea as to what temperature the sensor is seeing at the head.
Without a software method of looking at these parameters it all gets to be a PIA.
I have a Hammer but put together a simple interface to try the FREE software .
It is excellent.
The system is OBDI so your OBDII scanner is useless.
Good luck
Geoff
Good luck with this
Air temp compensation is very small . The head temp is a major element in fuelling level.
The head sensor is screwed into the front of number 3 head. The sensor connector is the white plug in the row on the LH side of the motor . If you pull the plug you will see it has two pins in a three pin housing.
A multimeter across the two pins will give an idea as to what temperature the sensor is seeing at the head.
Without a software method of looking at these parameters it all gets to be a PIA.
I have a Hammer but put together a simple interface to try the FREE software .
It is excellent.
The system is OBDI so your OBDII scanner is useless.
Good luck
Geoff
Good luck with this
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From: Belgium
Some news.
I took off one of the rotor caps just now, and they're a disaster area. The conductors are so pitted they look like the moon (same color too !)
I don't know if this is 'the' problem, but it certainly is 'a' problem. I'm getting new ones tomorrow (and rotors) and will update when fitted.
I'd post a pic, but I don't want to frighten you lot.
Peter R.
I took off one of the rotor caps just now, and they're a disaster area. The conductors are so pitted they look like the moon (same color too !)
I don't know if this is 'the' problem, but it certainly is 'a' problem. I'm getting new ones tomorrow (and rotors) and will update when fitted.
I'd post a pic, but I don't want to frighten you lot.
Peter R.
Three Wheelin'
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From: Bremerton, WA
Mine has had some hesitation and a minor misfire at idle so I orderd up a set of caps and rotors last week. Should get here Monday. I've not pulled mine but I suspect they are pretty bad considering the horrible condition of the air filter.. whith the PPI mised! OK.. I'll not go on that tirade again.
Good luck and I hope it fixes everything up. I say post the pics though.
Good luck and I hope it fixes everything up. I say post the pics though.
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From: Belgium
Originally Posted by black ice
Hi peter,
How long were those caps on? I recently got a 95, but don't know when the caps and rotors were changed, if ever - car runs pretty well, tho..
How long were those caps on? I recently got a 95, but don't know when the caps and rotors were changed, if ever - car runs pretty well, tho..
No wonder the old girl is billowing smoke and running 12 miles to the gallon. Poor thing.
Peter R.