Car cranks, doesn’t fire, no codes
Thread Starter
Cruising
Joined: Sep 2012
Posts: 11
Likes: 0
From: Indiana
Car cranks, doesn’t fire, no codes
Hi everyone. Hopefully I didn’t double post due to jumping between pages.
2004 C5 had the clutch go out at least a year ago. Life got busy and I finally buttoned it back up. Now it cranks, maybe fires once, but won’t start. No codes.
Theres fresh fuel in the rails. New battery (old one was questionable anyway). I even tried ground the engine directly, but I guess it wouldn’t turn well if it wasn’t grounded.
What am I missing? I had to have left something unplugged, but shouldn’t I get a fault?
2004 C5 had the clutch go out at least a year ago. Life got busy and I finally buttoned it back up. Now it cranks, maybe fires once, but won’t start. No codes.
Theres fresh fuel in the rails. New battery (old one was questionable anyway). I even tried ground the engine directly, but I guess it wouldn’t turn well if it wasn’t grounded.
What am I missing? I had to have left something unplugged, but shouldn’t I get a fault?
Moderator, Tech Contributor
Joined: Sep 2013
Posts: 15,627
Likes: 4,071
From: Cape Coral, Florida
Just spray some Brakekleen into a vacuum line like PCV or brake booster and see if the car starts or feels like it is trying to start...if it starts you have a fuel delivery issue...if not you will have to dig a little deeper...does the Tach move at all during cranking and check if you can hear the fuel pump prime for 2 seconds when the key is turned on...you can also see if you have spark during cranking...there is no one magic bullet !!
Thread Starter
Cruising
Joined: Sep 2012
Posts: 11
Likes: 0
From: Indiana
Well, back at it now that it’s spring.
The tach does not move when I’m cranking. I hooked up a OBD scanner and it does see engine speed. There is timing advance. I can smell fuel a little. It fires every once in a while.
I haven’t tried starter fluid yet, but that is a good idea. Fuel pump is priming. Fuel comes out when I depress the nozzle on the rail right when the key is on.
Could I have damaged the crank or cam position sensors or wiring? How would I check that?
The tach does not move when I’m cranking. I hooked up a OBD scanner and it does see engine speed. There is timing advance. I can smell fuel a little. It fires every once in a while.
I haven’t tried starter fluid yet, but that is a good idea. Fuel pump is priming. Fuel comes out when I depress the nozzle on the rail right when the key is on.
Could I have damaged the crank or cam position sensors or wiring? How would I check that?
Last edited by Gvr4 1510; May 8, 2020 at 05:53 AM.
Moderator, Tech Contributor
Joined: Sep 2013
Posts: 15,627
Likes: 4,071
From: Cape Coral, Florida
No spark and injector pulse is normally a bad crank sensor...pull of the plug wire off a coil pack and hold it about 1/2 inch from the coil and see if the spark jumps while cranking....if you have a fuel pressure gauge turn the key on and see if you have 55-62 psi or so....now crank the engine and see if the fuel pressure drops like a rock...another symptom of a bad CKP !!...or if you have a 12 volt test light you can check for injector pulse if you don’t have a pressure gauge !!...test light connected to battery POSITIVE...disconnect any fuel injector...probe the striped wire (NOT the pink wire) while cranking...if test light does not blink while cranking you have NO injector pulse !!...might be hard to see in direct sunlight.
