DOH! That pesky P0174

[Kristophe]

I thought cleaning my MAF would eliminate that occasional P0174 code it'd get but now this has happened twice within the past two weeks on my morning drive to work and the second time this morning; my car will hesitate with power loss but still run enough to make it to work and when I turn the engine off and start it back up no SES light and runs fine afterward. And the only code stored is P0174. Last weekend I replaced both pre-cat O2 sensors as routine maintance.

At 177K I suspect my MAF is on its way out. From what I've read the next time this happens I can dissconnect my MAF and see if the engine corrects itself?

[bcredliner]

From my experience when the MAF goes bad it stays that way until it is either cleaned or replaced. Assuming the MAF is malfunctioning--cleaning the MAF doesn't always work and even when it does it sometimes acts up again not many miles later.

Usually when the MAF is bad you will easily notice a loss in power and/or rough idle and engine roars more when you rev it. If your idle is rough, removing the MAF connector should smooth the idle out if the MAF is bad.

[squeasel]

I don't know if this helps but I had P0171 and P0174 and the culprit was a deteriorated air intake hose after the MAF but before entering block. My write-up is here FWIW ... http://www.xoutpost.com/bmw-sav-foru...174-fixed.html

[BigBlack48is]

+1 squeasel!

[Kristophe]

Sorry guys but I might should have mentioned in my post that I replaced my intake "elbow" last summer. At lunch today I decided to swing by my bother's and we pulled code P1347 this time. That would suggest the coil is going out on cylinder #3. Now THAT makes more sense. I'll do some more checking.

At least a coil is cheaper than a new VDO MAF

[upallnight]

Check the plastic line from the aux air pump to the egr valve and some of the plastic line to the CCV.

[Kristophe]

Originally Posted by upallnight

Check the plastic line from the aux air pump to the egr valve and some of the plastic line to the CCV.

Will do

[upallnight]

If you do decide to try a new MAF, buy a SIEMENS, not one of those cheap aftermarket.

A BMW 330 E46 uses the same MAF as some E53 3.0.

[Ricky Bobby]

check DISA seal for leakage as well, if the code is a misfire I'd look into a faulty coil or spark plug needing replaced.

[Kristophe]

Originally Posted by Ricky Bobby

check DISA seal for leakage as well, if the code is a misfire I'd look into a faulty coil or spark plug needing replaced.

I ordered a new Breimi coil today. I also ordered the DISA rebuild kit from G.A.S since I've now become paranoid (rightfully) about that retaining pin falling out in the intake and causing my engine unthinkable horror. So that should take care of any possible leaks (s) there.