please help 86 buick gn when starting warm or cold crank and cranks ( about 5- 8 second crank times)and them back fires it runs fine after starts only has problem when starting... any clues thanks glen
Welcome! Now, lets get to basics first! What do you have for a scan tool? What are your TPS IAC Cam sensor doing? Have you done any reading at GNTTYPYPE.org yet? Spring cleaning done? Any upgrades done to the car? What chip? Injectors? Etc etc etc. So tell us what you have car wise, scan tool wise, knowledge wise? Cheers!
Do you have an adjustable fuel pressure regulator or a guage to read fuel pressure? If not they are a great start to diagnose fuel related problems. Also, a modern chip from Eric @ Turbotweak burned for your setup would be a good start! Now, what about what Steve mentioned?
i adj the tps .46 it was at .40 this helps alot it starts up fine cold, but it still has hard time when hot, im going to put injetor cleaner in and new wires and new plugs and see it this helps, fuel pressure is 35lbs at ideal with vacuume hose off.
Thanks for the initial post, Steve. I think this is the problem with my intermittent startup issue. I'll verify by listening for the fuel-pump cuton and all that jazz you spoke of in post 2!! :cheers: :yup:
i took the car to a local and he put it on a engine tester, he said that every thing looked good, he said it might be the crank sensor going bad with long crank engine times, if so is it easy to change crank sensor?
Has anyone been in the engine on this car? A buddy of mine did the cam on his T and I'm not sure what he was smoking when he set the cam sensor but it was way out and his car did exactly what your describing yours as doing.
You might follow up on what Craig suggested and pop the top on the cam sensor and make sure the interupter wheel is still fixed in place...also make sure the body of the sensor is not loose and has turned a bit.
Won't hurt to look at the crank sensor and make sure it is not loose in its bracket, either.
re-did the pump test... turned on key and the pressure went up tp 40 psi, did not start the car, held pressure at 40 psi for more then 30 minutes is 40 psi too high???... is this saying the injectors are ok and are not leaking? i have green strip disk injectors
my next thing to do is look at the crank sensor and see if it oily and then adj the cam sensor... this is killing me :crazy: