Running lean.. First Cylinder on driver side

J

J_RAUD

New member
My MM thru a running too lean code.. So I checked the COPs, changed the injector and did a compression test.. The compression on that cylinder was 75 psi, all other cylinders were around 150psi.. So I did a wet test and the first test it jumped to 125psi and then to about 141psi... There's no smoke from my exhaust at start up or while running.. Well of course there was smoke after the wet test but I cleared.. Any help??
 
I am gonna say that you are having problem with a valve on that cylinder. Possibly a dropped seat.
 
I was thinking the same think MartyO... Cause there's no smoke anywhere.. Well when I get the time, I'll have to go in to her.. Do you guys recommend any mechanics on the Maryland side for these cars?
 
J_RAUD said:
I was thinking the same think MartyO... Cause there's no smoke anywhere.. Well when I get the time, I'll have to go in to her.. Do you guys recommend any mechanics on the Maryland side for these cars?
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Chris Vining is a member here.

Someone please pipe in with his screen name, I am having a bad case of CRS.
 
Is the car running bad? If the car is running okay you should look for other causes of the lean code. Vacuum leak, bad or dirty mass air flow sensor or ? If the car is not running bad I would hesitate to tear into the engine. Running a smoke test for vacuum leaks should be done after the car sits overnight.
 
RF Overlord said:
He said he did a wet compression check and it improved. Doesn't that clear the valves?
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Not always.

I am basing my guess on an Internet diagnosis which is just a guess.

I would urge him to get with Chris to have the car gone over.
 
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What was the fault code?

P0171/P0174? or something different?


I do OBDII calibration for a living.. May provide some additional non intrusive tests for ya...

No seasoned veteran here but ten years working for major OEM's.... I suppose the do call me a Senior Engineer these days...
 
RF Overlord said:
Then tell us how to disable all the I/M monitors without letting the state's equipment flag it...

OK, OK...can't blame a guy for trying. ;)
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No point in disabling.... Just calibrate to pass them instead of fail and not set the readiness bits that they looked at...

😎
 
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