No spark or fuel, whats wrong?
Thread Starter
Staging Lane
Joined: May 2006
Posts: 74
Likes: 0
No spark or fuel, whats wrong? This is on a 98 C5 i got about 2 weeks ago. I already swapped headgaskets and drive it for a week just fine.
Car was running good but had an exhaust leak so i tried to fix it. I unbolted the driver side header, dropped it down out of the way so I could retap the bolt holes and then bolted it back up. When i went to start it no fuel was getting to the motor.
I replaced the pump and checked all the fuses/relays and it was all good. Now you can hear the fuel pump running but checking the plugs their dry as bone if you turn the motor over. Checked for spark and didnt see anything either.
The fuel pump deal is weird at 1st it wasnt doing anything so my buddy jumped power to it at the relay w/ a power probe and that kicked the fuel pump on full blast. Took the jumper off and the fuel pump will run full blast the entire time the key is on like it goes to prime and doesnt shutoff. You can feel/hear fuel running in and out of the line to the fuel rail. Even like that no fuel is getting thru the injectors.
So whats going on? Is there a sensor back there that could have gotten broken. Ive looked over all the wiring i can see and its all good there including 2 grounds that I saw. This is driving me nuts and I cant take it to a shop i'd have to have someone come to me so i'd like to figure this out myself and quickly.
Car was running good but had an exhaust leak so i tried to fix it. I unbolted the driver side header, dropped it down out of the way so I could retap the bolt holes and then bolted it back up. When i went to start it no fuel was getting to the motor.
I replaced the pump and checked all the fuses/relays and it was all good. Now you can hear the fuel pump running but checking the plugs their dry as bone if you turn the motor over. Checked for spark and didnt see anything either.
The fuel pump deal is weird at 1st it wasnt doing anything so my buddy jumped power to it at the relay w/ a power probe and that kicked the fuel pump on full blast. Took the jumper off and the fuel pump will run full blast the entire time the key is on like it goes to prime and doesnt shutoff. You can feel/hear fuel running in and out of the line to the fuel rail. Even like that no fuel is getting thru the injectors.
So whats going on? Is there a sensor back there that could have gotten broken. Ive looked over all the wiring i can see and its all good there including 2 grounds that I saw. This is driving me nuts and I cant take it to a shop i'd have to have someone come to me so i'd like to figure this out myself and quickly.
Check the camshaft position sensor behind the manifold. The one sticking about 3" vertically out is the oil pressure sending unit, this one is below/beside it. The VATS resistor in you key might also be messed up, give another set of keys a try.
Originally Posted by Steve Burger
Did you check fuses?
Even though you said you did, I'd look again, particularly the underhood fuses. I blew a fuse and the entire passenger side bank was getting no fire.
The factory PCM will not release spark to the injectors or coils during cranking if it does not have a clean ignition and cam reference signal. You might follow the wires to the cam and crank sensors and check to make sure they are plugged in. Also check any ground wires that may connect to the chassis and engine. Maybe something was unplugged.If you have a way to read codes I'll bet you have one lurking by now. Good luck.
