P0174 is driving me nuts!
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P0174 is driving me nuts! I have had this code for month and I took it to my mechanic to see what is causing it.
He checked the fuel injectors,fuel pump,MAF,manifolds, and even smoked the system to check for vacuum leaks. Nothing was found. I needed my car for work,so I went to pick it up before he could check other things,really don't know what else he could check.
Anybody have any other ideas as to what it may be?
He checked the fuel injectors,fuel pump,MAF,manifolds, and even smoked the system to check for vacuum leaks. Nothing was found. I needed my car for work,so I went to pick it up before he could check other things,really don't know what else he could check.
Anybody have any other ideas as to what it may be?
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Most likely something in the fuel system. Low pressure because of fuel regulator etc. Both fuel trims are +25 at that point the pcm doesn't adjust it any higher and you must find why its not getting enough fuel. I would replace the fuel filter and a complete fuel system test including a driving test if needed to find the problem.
http://www.obd-codes.com/p0174
... but did he clean the MAF? (I had this problem and the solution was a good MAF cleaning, as the article above suggests.)
Are you running a K&N or oiled air filter?
... but did he clean the MAF? (I had this problem and the solution was a good MAF cleaning, as the article above suggests.)
Are you running a K&N or oiled air filter?
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Here's a few details.......
MAF never really got over 1.0 lb/min ar idle except when I reved up to 894/rpm when it hit 4.3988 lbs/min. Does that seem right?
MAF never really got over 1.0 lb/min ar idle except when I reved up to 894/rpm when it hit 4.3988 lbs/min. Does that seem right?
Last edited by Red97LT1; May 3, 2015 at 08:16 PM.
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first start with what p0174 means: the o2 sensor on bank 2 (passenger side) has read lean condition for longer than was expected... which the computer could not adjust for with extra fuel. so somehow someway, there was extra air passing the front o2 sensor on passenger side to make it read lean for an extended period of time to set P0174.
if you have only got P0174 (bank 2) and never got P0171 (bank 1) then what does that tell you?
if you have only got P0174 (bank 2) and never got P0171 (bank 1) then what does that tell you?
I'd look at the MAF under magnification and make sure the did it right. I'd
also burn the K&N and go back to paper. If you DD the car nothing good can come of using an oiled air filter.
According to GM, when K&N first trashed my car, the oil can also foul the O2 sensors...
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Got back from the garage again and found out that the upstream 02 sensor is bad.
Replaced it with one from another Z28 that was there and the fuel trims are hovering around the 0-1% mark. The 02 sensor was only 7 months old,but I guess they got bad. Good thing is it's under warranty so I'm getting another one shipped to me.
Replaced it with one from another Z28 that was there and the fuel trims are hovering around the 0-1% mark. The 02 sensor was only 7 months old,but I guess they got bad. Good thing is it's under warranty so I'm getting another one shipped to me.
Got the code today on my 99 Camaro with 123K miles on it, stock engine. Read a couple of threads about it, then opened the hood. Removed and cleaned the MAF (looked OK to me), then went to the PCV valve. The 3/8" hose fell apart in my hand! Replaced with some spare 3/8" fuel hose, then took it for a spin. Seems like the computer is resetting things (idle was not steady for a minute, then got steady), but the code is gone, and the exhaust seems to smell like it should. Will see if gas mileage improves. As usual, check the easy stuff first!