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Lopey Idle and intake pops on a cold start


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Yeah, try unplug the MAF and reset the DME also and see how the car drives.

I may try that tomorrow, I didn't have the time with stuff going on around the house this evening.  The Bosch MAF will be here tomorrow.  I did start the car and just let it warm up so I could get a log of what its doing from a stand still if you wanted to check it out.  towards the end I shut it off, unplugged the MAF, reset the codes (there weren't any though) and let it run for a few more minutes under the same log.

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When I got home today I took the AOS back out to check the o-ring, I thought maybe i damaged it or that it wasn't seated right, then put it back in, I put the Bosch MAF in then took it for a long enough drive for it to hit temp.  The issue may be solved.  I will drive it to work tomorrow to see how it does.  

 

I also made sure to log the trip, its available with the same log in information.

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That sounds promising. I look forward to seeing less crazy MAF reading. In your old logs, a lot of times, the engine was pegged at full rich with no a/f control at all at idle. O2 sensors flat lined at 0.7v or so (rich) and not swinging.

 

Yes, those AOS o-rings are easy to crush. I replaced all 4 on mine. You can use some rubber grease (or engine oil) to lube the new one to make it easier to install and less prone to damage as well. Also make sure the locking connectors click.

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Yes John. You, Loren and me all had mentioned the MAF but the OP did replace the newly replaced MAF with yet another new MAF in post #31. I assumed that was a Bosch unit as a response to our comments but it was not.

 

So this will be the first time a Bosch MAF is fit in this case.

 

And I've been wondering about that MAF since this conversation began.

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Yes John. You, Loren and me all had mentioned the MAF but the OP did replace the newly replaced MAF with yet another new MAF in post #31. I assumed that was a Bosch unit as a response to our comments but it was not.

 

So this will be the first time a Bosch MAF is fit in this case.

 

And I've been wondering about that MAF since this conversation began.

 

You are right.  The MAF was replaced for me free of charge once the first one seemed bad.  I figured the odds of the original Bosch, replacement non-Bosch then its replacement could all be the problems.  I just took another longer drive into town and was data logging the whole time.  The car feels much more responsive and never popped once.  The idle was nice and steady.  The big test will be Thursday morning, it supposed to be in the 30's around the time I leave for work so we'll see how the startup goes.

 

Side note (i reviewed the carfax late last night and saw where it was noted that the dealer changed the MAF around 41k miles on the car as well)

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Based on your last drive log (4:19pm today), everything looks pretty normal now! Warm idle MAF reads 4~5g/s..right on. Would be good to log the O2 sensor readings as well.

 

Let's see if it cures the cold start issue on Thurs.

Edited by Ahsai
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Based on your last drive log (4:19pm today), everything looks pretty normal now! Warm idle MAF reads 4~5g/s..right on. Would be good to log the O2 sensor readings as well.

 

Let's see if it cures the cold start issue on Thurs.

The time must be off.  I was definitely not home from work yet then.  I thought that I had the o2 sensor's on there???  I'll take a look.  I also took a reading with the manometer and its steadier even with revs.  its holding a 5.2 in H20

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Thanks for the update and I'll keep my fingers crossed for you :)

I want to call this one solved!  The cold weather start this morning was flawless!  It has power and responsiveness I didn't know it had.  This has been a long one, Plugs, tubes (leaking and cracked), boots (Cracked and torn), AOS, TB and intake tube cleaning (oily and dirty), lots of data logging and three MAF's (probably should have just been one!!!!) and I think its finally over!  While there were some contributors that probably were not helping, I'd say the primary issue was the non-Bosch MAF.  This should be a PSA or sticky, just because it looks identical doesn't mean its made identical.  Bosch MAF's ONLY in these cars!!!

 

A Big thank you to Ahsai and JFP for sticking it out with me, giving me feedback and reviewing my data!  I would have been lost!

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Is true of all sensors, spark plugs and coils, OEM parts turn out the cheapest in money and time. Happy for you that it is resolved.

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Thanks for the update and I'll keep my fingers crossed for you :)

I want to call this one solved!  The cold weather start this morning was flawless!  It has power and responsiveness I didn't know it had.  This has been a long one, Plugs, tubes (leaking and cracked), boots (Cracked and torn), AOS, TB and intake tube cleaning (oily and dirty), lots of data logging and three MAF's (probably should have just been one!!!!) and I think its finally over!  While there were some contributors that probably were not helping, I'd say the primary issue was the non-Bosch MAF.  This should be a PSA or sticky, just because it looks identical doesn't mean its made identical.  Bosch MAF's ONLY in these cars!!!

 

A Big thank you to Ahsai and JFP for sticking it out with me, giving me feedback and reviewing my data!  I would have been lost!

 

 

Don't be down on yourself about getting the wrong MAF, a lot of people have learned the same lesson the hard way.  I'm just glad it is finally sorted.

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Glad to hear that! This must be the longest MAF thread on renntech and thanks for the reps. Appreciate those.

 

Looking back...this could have been solved on page 1 after post #14 :)

 

SHHHHHHHHHHHHHHHHHHH!!!!!!! Lol.  Lesson learned.  And on the brightside... there was some possibility that the AOS was on its way out... right?  maybe?  The tubes and boots where definitely bad, I have pics of those.

 

 

Thanks for the update and I'll keep my fingers crossed for you :)

I want to call this one solved!  The cold weather start this morning was flawless!  It has power and responsiveness I didn't know it had.  This has been a long one, Plugs, tubes (leaking and cracked), boots (Cracked and torn), AOS, TB and intake tube cleaning (oily and dirty), lots of data logging and three MAF's (probably should have just been one!!!!) and I think its finally over!  While there were some contributors that probably were not helping, I'd say the primary issue was the non-Bosch MAF.  This should be a PSA or sticky, just because it looks identical doesn't mean its made identical.  Bosch MAF's ONLY in these cars!!!

 

A Big thank you to Ahsai and JFP for sticking it out with me, giving me feedback and reviewing my data!  I would have been lost!

 

 

Don't be down on yourself about getting the wrong MAF, a lot of people have learned the same lesson the hard way.  I'm just glad it is finally sorted.

 

Thanks man!  I appreciate it!

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