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Sharing my BAD MAF Experience, This one is confusing and misleading.

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Sharing my BAD MAF Experience, This one is confusing and misleading.

 
Old 09-10-2009, 05:09 PM
  #1  
ShokWaveRider
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Default Sharing my BAD MAF Experience, This one is confusing and misleading.

It all started when I got the following ECU errors:

1) PSM ABS Lights came hard on after a WOT acceleration in 2nd gear. The car seemed to stutter for a second, (Like Fuel Injectors shut down for a sec or the throttle bosy closed) then continued as normal.

2) Stopped turned off ignition started again PSM and ABS Lights hard on. Everything I read says that they come on after aggressive driving in most cases and go out after a shutdown and restart. Not the case this time.

3) Drove the car easily got 1.1bar with no apparant hiccups. I then went home and plugged in Durametric Logger the following errors were noted:

PSM/ABS 5525 General Fault of "Torque tranfer from DME disturbed at times"

P0102 MAF Error "Mass Air Flow Sensor - Below Lower Limit"


4) Tried to reset them but no luck.

5) Disconnected the battery for 15 mins

6) Restarted the car, No lights for 15 seconds then both PSM and ABS lights again hard on. Same durametric Errors


No CEL light during all this.

So I read all the posts some said MAF, and others had horror stories about ABS controllers and BAD DME (All dealer diagnosed and replaced).

Being cheap and not relishing the thought of a new DME 7.8. I took the MAF out and cleaned, it as recommended but still no joy same problem. Re-Flashed my DME 7.8 back to stock just in case, and this made no difference. Except I saw the P0102 error more frequently on the stock Flash. When I cleared the P0102 it just comes back. Cannot clear the 5525 at all without disconnecting the battery.

I also did a pressure test at 10-15 psi at the air intake and I could not hear any air leaks, other than out the oil fillter cap.

Again being cheap, I thought I would take the easy way out first. I ordered a MAF from Pelican Parts for $233.50.

Here are the Durametric numbers for the Duff MAF at Idle and 2500 RPM:

MAF Air flow (HSM)= 24.7 Kg/h at 777 RPM and 60 or so at 2500 this does seem to move OK.

Hot Film MAF Voltage = 1.04 all the time.

The Other MASS Air Flow reading was a solid at 3 all the time.


Well it appears a replacement MAF fixed the problem...... for Now. I reset all the codes and all is well. It arrived today and everything is back to normal. Thank @#$% or whoever you like!

Here are some Durametric numbers for the good MAF

RPM: 777 (Idle)
Mass Air Flow (HFM) 20 Kg/h
Mass Air Flow 20.7 Kg/h
Hot Film MAF 1.35 Volts

RPM: 1500
Mass Air Flow (HFM) 43 Kg/h
Mass Air Flow 37.6 Kg/h
Hot Film MAF 1.61 Volts

RPM: 2552
Mass Air Flow (HFM) 63 Kg/h
Mass Air Flow 66.8 Kg/h
Hot Film MAF 1.92 Volts


I hope this helps some one.
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Old 09-11-2009, 03:36 AM
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Thanks for posting the details.

Given the durametric data from the bad maf, I don't see what was misleading- seemed pretty well bad from the get go.

But given the lack of quantitative data in other reports of 'bad mafs' I suppose that part was the confounding part..
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Old 09-11-2009, 07:46 AM
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Originally Posted by adam_ View Post
Thanks for posting the details.

Given the durametric data from the bad maf, I don't see what was misleading- seemed pretty well bad from the get go.

But given the lack of quantitative data in other reports of 'bad mafs' I suppose that part was the confounding part..
The problem I had is no one had actually posted what a bad one looked like from a Durametric/Technical Parameter Perspective. So I have nothing to compare it with. As the main flow was being read, incremented and decrimented as expected so therefore looked normal (To Me). The voltages were all out, but I had no benchmark to tell me so.
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Old 09-11-2009, 11:13 PM
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Originally Posted by ShokWaveRider View Post
Drove the car easily got 1.1bar with no apparant hiccups.
That's a lot of boost (and hard on's!) - your car must be flashed. Do a search to read about many others with high boost levels triggering those lights and damaging the MAF sensor!
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Old 09-12-2009, 08:10 AM
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Originally Posted by WCE View Post
That's a lot of boost (and hard on's!) - your car must be flashed. Do a search to read about many others with high boost levels triggering those lights and damaging the MAF sensor!
Yes Softronic. 1.3 bar K24 Flash.

Current Mods Include:

1) Silicone "F" Hose
2) Billet diverter Valves with 23 - 30 psi (Blue) Springs
3) 1 Bar Waste Gate Actuators Set to 11-12psi cracking pressure
4) Custom Designed Headers
5) FabSpeed 200Cell Hi Flow CATS mated to a Gen II Max Flow Exhaust System

That is all I will be doing also. Unless I decide to install Water/Meth Injecton for extra cooling only). I am still debating the benefits vs Cost.
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Old 07-19-2016, 11:38 AM
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Get a Protomotive MAFLESS Tune and get rid of that junk that always is breaking.

Originally Posted by ShokWaveRider View Post
Yes Softronic. 1.3 bar K24 Flash.

Current Mods Include:

1) Silicone "F" Hose
2) Billet diverter Valves with 23 - 30 psi (Blue) Springs
3) 1 Bar Waste Gate Actuators Set to 11-12psi cracking pressure
4) Custom Designed Headers
5) FabSpeed 200Cell Hi Flow CATS mated to a Gen II Max Flow Exhaust System

That is all I will be doing also. Unless I decide to install Water/Meth Injecton for extra cooling only). I am still debating the benefits vs Cost.
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Old 08-31-2017, 02:19 PM
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Originally Posted by ShokWaveRider View Post
It all started when I got the following ECU errors:

1) PSM ABS Lights came hard on after a WOT acceleration in 2nd gear. The car seemed to stutter for a second, (Like Fuel Injectors shut down for a sec or the throttle bosy closed) then continued as normal.

2) Stopped turned off ignition started again PSM and ABS Lights hard on. Everything I read says that they come on after aggressive driving in most cases and go out after a shutdown and restart. Not the case this time.

3) Drove the car easily got 1.1bar with no apparant hiccups. I then went home and plugged in Durametric Logger the following errors were noted:

PSM/ABS 5525 General Fault of "Torque tranfer from DME disturbed at times"

P0102 MAF Error "Mass Air Flow Sensor - Below Lower Limit"


4) Tried to reset them but no luck.

5) Disconnected the battery for 15 mins

6) Restarted the car, No lights for 15 seconds then both PSM and ABS lights again hard on. Same durametric Errors


No CEL light during all this.

So I read all the posts some said MAF, and others had horror stories about ABS controllers and BAD DME (All dealer diagnosed and replaced).

Being cheap and not relishing the thought of a new DME 7.8. I took the MAF out and cleaned, it as recommended but still no joy same problem. Re-Flashed my DME 7.8 back to stock just in case, and this made no difference. Except I saw the P0102 error more frequently on the stock Flash. When I cleared the P0102 it just comes back. Cannot clear the 5525 at all without disconnecting the battery.

I also did a pressure test at 10-15 psi at the air intake and I could not hear any air leaks, other than out the oil fillter cap.

Again being cheap, I thought I would take the easy way out first. I ordered a MAF from Pelican Parts for $233.50.

Here are the Durametric numbers for the Duff MAF at Idle and 2500 RPM:

MAF Air flow (HSM)= 24.7 Kg/h at 777 RPM and 60 or so at 2500 this does seem to move OK.

Hot Film MAF Voltage = 1.04 all the time.

The Other MASS Air Flow reading was a solid at 3 all the time.


Well it appears a replacement MAF fixed the problem...... for Now. I reset all the codes and all is well. It arrived today and everything is back to normal. Thank @#$% or whoever you like!

Here are some Durametric numbers for the good MAF

RPM: 777 (Idle)
Mass Air Flow (HFM) 20 Kg/h
Mass Air Flow 20.7 Kg/h
Hot Film MAF 1.35 Volts

RPM: 1500
Mass Air Flow (HFM) 43 Kg/h
Mass Air Flow 37.6 Kg/h
Hot Film MAF 1.61 Volts

RPM: 2552
Mass Air Flow (HFM) 63 Kg/h
Mass Air Flow 66.8 Kg/h
Hot Film MAF 1.92 Volts


I hope this helps some one.

Hey ShokWavRider, yes, this does help quite a bit. I had a very similar experience.

I was WOT in first gear in my 00 Boxster S, and the engine spins up much faster than stock as I have added a fairly sticky clutch and an Aase lightened flywheel.

Right when I hit about 6500 rpms the car just stopped, I almost hit my nose on the steering wheel. It was pretty violent. So, immediately let off the gas and start coasting to the side of the road, as I realize that the car died, and I restart it, which it starts right up, but, now it won't idle.

I pull into a parking lot and for a couple mins blip the throttle and nothing seems awry except that it won't idle.

Since I'm less than 1/2 mile home, I proceed to drive slowly home. By the time I get home, the car idles, and the CEL is on.

I pull the codes via my durametric and get a P1130 O2 sensing adaptation idle range bank 2. P0153 O2 sensor ageing ahead of cat cyl 4-6, P0102. The next day I clear all the codes, and believe it or not, the car runs OK, a bit of hesitation from idle, and a bitt bumpy from idle, and it doesn't fly thru the rpm range like before.

So, I've driven it around for a few days, and cannot get rid of the P0102 for the MAF Sensor below limit value.

My numbers are almost identical to yours here. I will post them once I download them, but, I was trying to determine whether or not to just replace the MAF.

Now I know it need replacing.

What I think happen is that it broke right in the middle of that acceleration and the car's DME just didn't know what to do. So, all those other secondary codes flashed, and then the car adapted as it is no longer getting correct values from the MAF.

I'll update this in a few days when I replace the MAF and will post my before and after values as well.

Thanks AGAIN!!!

Brian
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Old 08-31-2017, 08:36 PM
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its astonishing how badly these cars can run, all for the want of a new clean hot wire maf. i recently replaced mine to cure an idle hunt, and all is perfect again.
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