1997 ranger 3.0 auto… took it to a shop to have some work done. trans fluid valve covers leaking. had no real probems with the truck.
now, first start in the AM and only them, it runs lean and dies. second start Ok rest of the starts during the day OK
replaced ICV, tosses no codes. fuel pressure Ok
help, any thoughts.
How quickly does the fuel pressure bleed off after the fuel pump stops running?
I had the same problem with my Ford Explorer 4.0L V6. I checked fuel pressure, cleaned the throttle body and IAC, and finally settled on the intake manifold gaskets. Cold, they would leak a little until the engine warmed them up just a tad, maybe a minute. Then, it was good the rest of the day. It took 6 months of this bizarre action to set the ‘check engine’ light with a code telling me it was detecting a lean burn.
thank you…they did take off the intake…sounds like the problem.
to busted knuckles
did you replace the gasket or just snug it down. I have a new gasket on the intake now,
I replaced the gaskets. A Fel-Pro set of upper and lower gaskets was less than $20, so I did them all. The old ones looked Ok, slightly compressed but no cracks or breaks and seemed pliable, not hard. But the new gaskets solved the problem. Do you know if they replaced both the upper and lower gaskets?
I just think just the upper. he just needed room to get to the valve covers. but I will replace both.
anything to fix the problem. thank for your help. no one else seemed to have the same problem.
Gaskets make sense, as the thermal expansion from the hot engine could close them off, then they’d open when the engine got cold. If it doesn’t turn out to be the gaskets creating an air leak, be sure to pay att’n to @Tester 's comment above. It could be the fuel pressure check valve is leaking, or an injector is leaking. The low fuel pressure will cause a lean condition after the car has been sitting for an extended time between starts.