I have a 95 GT and have been getting a check engine light intermitantly ever since I had a rebuilt engine installed. The codes are 172 and 176, (left bank lean), and (right bank lean). It occures randomly and will stay on at idle, but I have only ever seen it come on at power, never comes on at idle. It may come on for a minute or two and go off for a minute or two, totaly randome. The engine is a stock rebuild except for a Ford Motorsport E303 Cam (I think, whichever is the mildest of the 303 series). It has headers, H pipe exhaust, cold air intake, no cats, and the smog pump has been removed, all of this was done well before the engine change. So far, I have changed the O2 sensors, didn't fix. I checked the vacuume and it is 21psi at idle, no problems there. I cleaned the MAF sensor with CRC MAF sensor cleaner, no change. I do not have a fuel pressure guage, but I capped the vacuume on the fuel pressure regulator which should have raised the pressure by 5-8 psi, no change. When the engine was installed I put in a new fuel pump, new stock injectors, new fuel filter and new idle air controller. I pulled some of the plugs and they have a light grey color, which if i remember right is good. The car runs strong and has smooth idle, other than the light I can't tell anything is wrong. It does hesitate a little when pulling out, if you don't let it warm up in the morning, but it did that before the rebuild. I just don't want to damage the engine if it is running lean. I can't think of what else to check, at this point I am stumped. All suggestions welcome.
HELP with lean trouble code
- Thread starter jake00574
- Start date
jake00574 said:
How do you know there was no fuel pressure change if you dont have a gauge? Removing the FPR line is what raises the pressure (to simulate WOT).
Recheck your manifold vac.
Check things like the PCV valve to make sure it seals tight and hasnt popped out.
Good luck.
I am going to pick up a fuel pressure tester this weekend. When I disconected the pressure regulator line I was hoping the pressure increase would make the problem go away, thinking maybee the 303 cam was requiring the engine to need some more fuel, guess not. I do however want to make sure the pressure was at least in the correct range so I am getting a guage. I will recheck the vacuume and look at the PCV valve and seal.
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