I NEED A REAL GURU ON THIS ONE!!! 1993 GMC K1500 5.0L Have changed most of the fuel system but still having issues of not wanting to start.
The truck is a standard cab with an 8ft bed and 131" wheel base if that makes any
difference. So here is the scenario: the truck was having issues of starting and then
would start to stall and I would need to feather the gas pedal to keep it running then do
the two foot keeping the idle up and braking at lights to keep it from stalling to get it
home. Did the Seafoam cleaning regimen in the throttle body, ran the motor a bit to clean
it out and then changed plugs, wires, cap, rotor. Started and idled fine but the problem
immediately came back when I went for a drive. Since then have installed new fuel pump,
lines, pressure regulator, injectors, and throttle position sensor. Went for a drive and
seemed to fix the problem. The same day I went back to start the vehicle and the same
problem popped up again. This time it was a full tank of fuel but thankfully the pump had
already been changed and is working properly so that is ruled out. Thinking of it now I am
going to change the gas cap as well as that may be a problem but, beyond anything I
have replaced, what other items parts could be causing this issue?? Give me a
possibilities list in progression and I will eliminate each as I go to zero in on the problem.
It sounds like others have had this issue but I haven't found where there has been a
specific solution. Any help from a true guru would be greatly appreciated!! Thanks!! SK
Have you done a compression test all cylinders?
Compression on all cylinders is good. The engine has 75,000 on it and when it decides to run it runs beautifully. Now that I have replaced the injectors and pressure regulator it runs (when it decides to start) even better than it did before. A lot more consistent power on highway hills. It fired up this morning, I let it run for awhile, took it down the road and back, and now coming back to it to 4-5 hours later and try and start it, it will not kick over. I sprayed a bit of starting fluid into the open flaps and it tried to kick so I getting spark. This thing has me totally stumped. When it starts it runs perfect and idled perfect. Like new. When it doesn't want to start it just won't. If I come back in about 4-5 hours it wouldn't surprise me if it kicked right over. What on earth else could ther be short of changing the ECM could it be???? And the issue is not temperature related as it would do this cold or marginally warm here in New England. This truck ran perfect until this situation popped up before changing anything fuel or electronic related. So, that tells me it is either a part that has worn out that can create an intermittent issue or a condition that can arise from a part that is on it's way out none of which I have described being already replaced, know what I mean?? Really need my damn truck!!! Grrrrr.......
Is there something in the ECM that would tell the injectors to throw a little fuel down the throttle body on start up that may be an intermittent issue or would something like that just let go and not operate at all? Can't think of anything else.
Oh, and I have changed out the gas cap just in case there was an air lock issue. The old cap did have a bit of stickiness to it when I sucked on it. And yes, I put my mouth on it and sucked on the thing, lol, because there really is no other way to test the thing properly. :) So aggravated at the moment. :(
Check your grounds. Especially the block to frame