Truck won't start
The best test is the presence or absence of a good, strong spark at the plugs. If you've got that good spark, the coil's fine.
I've seen coils fail such that the spark got weaker as the coil got hotter, but that failure mode can't happen during a cold start.
I've seen coils fail such that the spark got weaker as the coil got hotter, but that failure mode can't happen during a cold start.
OK, I started diagnostics today. Fuel pressure is good. I checked the resistance on all of the injectors and they were fine. I checked the fuel and ASC relays and they were fine.
While checking all of the spark plugs for spark the engine started while I had the #6 wire off. When I replaced it, it wouldn't start the first time, but will start now. When I get to about 3000 RPM it runs real rough, like it is missing a few cylinders. I don't believe it can be the dist cap or rotor, as they are new and I was having problems before replacing them. Where should I go next?
Thanks,
Ken
Oh, I checked the resistance on the coil and it was good.
While checking all of the spark plugs for spark the engine started while I had the #6 wire off. When I replaced it, it wouldn't start the first time, but will start now. When I get to about 3000 RPM it runs real rough, like it is missing a few cylinders. I don't believe it can be the dist cap or rotor, as they are new and I was having problems before replacing them. Where should I go next?
Thanks,
Ken
Oh, I checked the resistance on the coil and it was good.
Last edited by BoneEOD; Jun 4, 2010 at 05:57 PM.
Entirely possible. Incorrect airflow readings will give you too much/not enough fuel to burn. Check the map sensor (on the front of the throttle body), make sure it is plugged in good, is seated well in its spot......
Yes, not sure how removing the one spark plug wire and watching it for spark could get the engine to start!
I removed the pre-cat and all the sputtering stopped and it will now go past 3000 RPM. I wish I could have seen this before when I tried it, but that is the way it goes.
I guess I will drill out the cat, need to find directions on here. I could have bought a new cat with all of the money I wasted not doing proper diagnostics and don't have enough money now to do so. Arrgg!
I removed the pre-cat and all the sputtering stopped and it will now go past 3000 RPM. I wish I could have seen this before when I tried it, but that is the way it goes.
I guess I will drill out the cat, need to find directions on here. I could have bought a new cat with all of the money I wasted not doing proper diagnostics and don't have enough money now to do so. Arrgg!







