Air lid causing P0171 & P0174 codes
Air lid causing P0171 & P0174 codes I've noticed lately that my '02 Z28 just hadn't felt as responsive as it once was and also noticed some pinging under WOT. Didn't think much of it because I haven't been racing it and just chalked it up as bad gas, bad air etc.
Saturday night I got the dreaded "Service Engine Soon" light and once I got home, I hooked up the scan tool and I got 4 trouble codes, all relating to a lean condition on banks 1 & 2 (2 of the codes were just duplicates).
Monday afternoon I checked for obvious things under the hood but it all checked out so I started to pull things off from the front, starting with the air lid. Once I got everything off up to the MAF, this is what I saw. See pic #1
I'm not a fan of removing MAF screens and the 1st thing that popped into my head was THANK GOD I DIDN"T REMOVE THAT SCREEN!!
I could see where there was a large area of dust on the til of the cover where it meets the MAF. I noticed that the TSP air lid had just enough gap that a decent amount of air was going around the filter and being sucked directly into the MAF. See pic #2. It is underneath and in the back and without the trail of dust, it would have been hard to notice. This explains the large debris that otherwise could not get pulled through the filter. Notice the indentation in the molding of the lid which is where the leak was.
I put some RTV sealer in the gaps and then put some foam weatherstripping around the inside of the lid where it seals against the filter.
This fixed the problem completely. My car is once again scary responsive, no more pinging and no more codes. I did a normal drive for about 30 minutes and then a WOT blast, everything perfectly fine. Still, 4 days later and it's fine.
Saturday night I got the dreaded "Service Engine Soon" light and once I got home, I hooked up the scan tool and I got 4 trouble codes, all relating to a lean condition on banks 1 & 2 (2 of the codes were just duplicates).
Monday afternoon I checked for obvious things under the hood but it all checked out so I started to pull things off from the front, starting with the air lid. Once I got everything off up to the MAF, this is what I saw. See pic #1
I'm not a fan of removing MAF screens and the 1st thing that popped into my head was THANK GOD I DIDN"T REMOVE THAT SCREEN!!
I could see where there was a large area of dust on the til of the cover where it meets the MAF. I noticed that the TSP air lid had just enough gap that a decent amount of air was going around the filter and being sucked directly into the MAF. See pic #2. It is underneath and in the back and without the trail of dust, it would have been hard to notice. This explains the large debris that otherwise could not get pulled through the filter. Notice the indentation in the molding of the lid which is where the leak was.
I put some RTV sealer in the gaps and then put some foam weatherstripping around the inside of the lid where it seals against the filter.
This fixed the problem completely. My car is once again scary responsive, no more pinging and no more codes. I did a normal drive for about 30 minutes and then a WOT blast, everything perfectly fine. Still, 4 days later and it's fine.
hmm.. my factory lid was like that? but my seal came off on the way back from florida when i bought it. the clear tape holding the seal on came off and got on the screen covering a good 1/3 of the maf up. the engine would have a rough idle and buck, i had to give it wot just to move so i pulled over and saw that on the screen.
+1, glad i didnt remove the screen.....
+1, glad i didnt remove the screen.....
I bet I just had the same exact thing happen to me too, but havent got my car on the scanner yet. SES Light just went off. My TSP just doesnt fit that great. Mine has a gap in the back too and Im wondering if this could be it. I might have to go out in the garage and look at this. Damn I wish I could get my lid to fit better.
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My TSP lid kind of fits a little crooked in the two slots by the MAF. Maybe if I can find another lid used I may just pick it up. I don't think the quaility of my TSP lid is worthy of $100. They said all lids are the same, but I don't know about that assumption now. Proper fitment is very, very important.
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Originally Posted by irnbru83
I don't have nearly that much crap on my screen, but it could have been a gap in my old air filter / lid setup... With the k&n and the rubber seal, seems like my lid is on pretty tight now.
I am about to buy a lid for my car, is the SLP lid the one that fits good?
Originally Posted by speedfreak440
I am about to buy a lid for my car, is the SLP lid the one that fits good?
Joined: Nov 2003
Posts: 6,216
Likes: 236
From: Wichita KS / Rancho San Diego
Originally Posted by Marblehead
I've noticed lately that my '02 Z28 just hadn't felt as responsive as it once was and also noticed some pinging under WOT.
Once I got everything off up to the MAF, this is what I saw. I could see where there was a large area of dust on the til of the cover where it meets the MAF. I noticed that the TSP air lid had just enough gap that a decent amount of air was going around the filter and being sucked directly into the MAF.
Once I got everything off up to the MAF, this is what I saw. I could see where there was a large area of dust on the til of the cover where it meets the MAF. I noticed that the TSP air lid had just enough gap that a decent amount of air was going around the filter and being sucked directly into the MAF.
Originally Posted by 02SS0384
If your willing to shell out some money the SLP Blackwing fits perfectly. It's OEM fit and quality.
Staging Lane
Joined: Jun 2006
Posts: 83
Likes: 0
From: austin tx.
quick note....just recharged my K&N ..and i noticed that when i attached the little casing up under the filter ,on the filter ,up in the lid, then put it all back down in the box,that little itty bitty gap i once had is no longer there,actually, i had pulled the lid off a few times and had gotten use to the way it fit until i looked at it closely,and i guess the previos owner ,sort of half ***,would put it all back together..just a little info...
12 Second Club
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Joined: Aug 2005
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From: Chesapeake,va and Charlotte,NC
I think my factory air lid has a little gap on the side of it somehow. Cause one time my maf screen was covered in grass. Im gonna check it again tonight, but my slp lid comes on monday.
Damn its a good thing you didnt descreen your MAF. Youd be in bad bad shape my friend. Well I just bought a TSP smoked lid so I hope it fits better than some of you guys were saying. I may just be keeping my SLP if it doesnt fit right. I guess Ima have to check my MAF aswell.