[Grn96Taurus]

First off - if this was posted with the same symptoms I apoligize...

'96 3.0L 111,135 Miles. P&P upper intake, Gutted MAF, cone fileter...

Im constantly getting a running lean code p0171/0174 IIRC, which is running lean front and rear banks. The code has only been thrown on normal driving conditions, I.E - not flooring it or revving it up constantly. Now, I have replaced almost every gasket on the upper part of the motor and double, even triple checked the torque specs. The gutted MAF and intake setup have not given me any problems up until ~ 8 months or so ago when I first got the code. Ive had the P&P/MAF/Intake setup for approx 2 years prior to this code with NO problems...The only thing that is activly wrong with the engine is the IAC is going bad and it needs a serpentine belt.... Ive replaced/tested the following:

Replaced all 4 O2's
Replaced TPS
Replaced UIM Gasket
Replaced EGR Gasket
Replaced PCV Valve
Replaced in line Fuel filter
Tested Fuel pressure at shrader, KOEO, KOER everything in normal spec, incl. FPR
Checked all vac lines to intake and sensor connecotrs
Ive run many bottles of FI cleaner through the system


The only thing that I can see going wrong is the MAF sensor is failing, but on a eec-v/obd-II system that would throw a "MAF out of range" or equivilant code right?

I do have a spare MAF/sensor and intake hose that I will be swapping out soon to see if this will remedy the problem. Does anyone else have any imput concerning what else to look at? Im pretty much stumped, and the maf swap is the only thing that I have left up my sleeve of tricks.

 

[gtx2000]

Got to remember if it says it is running lean doesn't mean that it is. running lean is only telling you that there is abundance of air in the system. You could have a misfire in that bank or no spark at all and it will induce to much air into the system and the 02 sensors will think it is lean but it isn't I would start out checking the plugs and wires make sure the spark plug tips are in normal condition. Not black or grey this indicate lean or rich conditions.

 

[silvapain]

the misfire code is different. I'd replace the MAF housing. it's not getting a proper reading on the amount of air. The MAF itself won't throw a code, because it's doing what it should. also, if you have a K&N filter, I would clean the MAF sensor with electrical contact cleaner too. the extra airflow across the wires have probably brought alot of oil along with it.

 

[Grn96Taurus]

GTX - plugs and wires were replaced 3 days ago. The failure of a plug would bring along a stumble in the ignition, misfire code and rough idle and general running - non of which my car has. Running lean/rich with it not really running lean/rich would also indicate failing o2 sensors, which was the first thing that I changed out.

Silva - Thanks for the backup with the idea. I don't have a K&N cone/panel filter on my car - the one I have is not oiled. I have some spare MAF sensors laying around the garage I will swap them out.

Also, is there anyway to test the maf sensor using a heafty amount of DIY tools? Or shouldn't I worry about this?

 

[gtx2000]

I agree with you on that but you did not mention that you had did that already. Not too mention some people dont even notice a miss in there car.

 

[silvapain]

I ported my MAF too, and had to replace it because the engine was running too lean.

You need a multimeter to test the voltage across the sensor. Here's what the Haynes manual says to do:

backprobe the MAF signal (+) and ground (-) terminals with a voltimeter. Start the engine and check the voltage, it should read between 0.5 and 0.7 volts at idle.

increase the engine RPM. The signal should increase to about 1.5 to 3.0 volts.

Hope that helps.

 

[Guest]

How is the accordion behind the maf?

 

[Grn96Taurus]

Originally posted by XLSuruaT@Mar 7 2004, 11:45 PM
How is the accordion behind the maf?

Silva - once again man, good information.. Thanks for the tip I didn't even know the haynes had that info in there! go figure!

what accordian

I don't need no stinkin accordian!!!! Don't have one

 

[Guest]

Originally posted by Grn96Taurus@Mar 8 2004, 06:12 PM
what accordian

I don't need no stinkin accordian!!!! Don't have one

That thing right before the intake? You dont have that!?

 

[gtx2000]

Look at my previous post this is a 1990 car here:
But mines an 87 but i converted the wiring and ECM too 1990

NOTE: wide open intake no small puny intake MInes totally new and i think i got something internal going on im trying to debate ripping apart the engine got new trans in there

 

[-qaz-]

I agree with the MAF theory. I'd say o2 also but you changed those already. From what i understand of how the MAF works you shouldnt try to gut it out, but you had it for 2 years... so i dont know. Cleaning the maf with electrical contact cleaner as adviced before might also help. Oh and also i think you'll get a MAF failure code only if it reads more then 5v or something... dont remember.