hey everyone i was driving down the road yesterday and went to pass a car and right after i punch it and im up about to go by the car my truck shuts off.i pullover and try to start it back up and it acts like it is out of time.so i figured i jumped a tooth on my timing so i take everything off down to the timing chain and the timing chain is fine marks line up perfectly.now it cranks over like it is in time but will not start still. i am getting fuel but not spark.i took the ignition coil in and it tested bad so i replaced it and still no spark ignition module under the hood tested fine but i heard someone say something about an ignition module in the steering wheel? any ideas would help. thanks.
truck won't start no spark?
- Thread starter 99yukon
- Start date
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961500
Is it 2012 yet?
Do you have codes. sounds like mine after I rebuilt it I was missing the crank ring though. Have you cheked your crank position sensor it relays rpm and timing to your ecm. sorry to say with our its a pain to diagnose I even had to rewire the crank senor harness because it was giving a bad signal and making the truck cutoff and run rough.
i unhooked the battery a few times so i don't think i have any codes.i replaced the crankshaft position sensor and it still acts like it is out of time it will crank over and stop sometimes it will backfire out the throttle body.i guess it has spark now because it acts like it wants to start sometimes but not all the time seems like the timing is way out of whack somehow.
961500
Is it 2012 yet?
On this seris truck if it is more than 2 degrees out of position it is not supposed to send a coil spark. As far as codes you may have some older codes still there you need to see if there are any it may help pinpoint the issue.
ravingmadman
Chief Knuckle Buster
Did you replace the one on the distributor, also? There are two sensors. You'll eventually get a P1345 code IIRC if this is your problem. I'd also do an idiot check, and just unsnap/resnap the harnesses on the distributor. When you disconnected the battery, did you let it sit for a couple minutes? Try that too, although you will lose some of the codes, if not all.
Are you sure you're getting fuel? My experience (and humble $0.02) is that electrical problems I've had with our rigs have caused poor running for a short period of time, and then failure, whereas fuel problems have been immediate, and brutal. Instant death, and no codes was the fuel pump for me.
Best of luck to you, sir!!
Edit: Definitive troubleshooting steps- Have a buddy help you. Pull a spark plug wire off, hold the plug wire end close to the plug and crank it over. If you see a spark jumping across, you've got spark. You'll probably shock the crap out of your hand, too, but it won't kill you. Just a little kiss from your hoe. No spark- could be a number of things, but any one of them should throw a code. If you have spark, when you first turn the key to 'on,' you should hear the fuel pump whine/engage for 2 seconds, then stop. If you don't hear it, your fuel pump pooped the bed. If you have spark to the plugs, and a good fuel pump, then your timing is hosed- go for the other crank position sensor on the distributor? Look for more codes?
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ravingmadman
Chief Knuckle Buster
What was the update on this?
