99 Yukon wont start

[TechGirl]

I cant get my 99 Yukon with 340,000 miles to start after installing a new timing chain.
Checked the fuel pump relay, distributer, and crank sensor.
All seem to be working fine.

Only thing I can figure is the security system shut down. About 5 yrs ago someone tried to steal my baby and busted the ignition swith. I had a new one installed.

Any ideas on what to check or how to get my baby back on the road would be great.

 

[JKmotorsports]

Were the timing marks on the crank gear and cam gear lined up when the chain was installed? If not, then the cam timing will be off and keep it from turning over.

 

[TechGirl]

Yep, made sure the timing marks on the crank gear and cam gear were lined up when the timing chain was installed.

 

[hapyspaz]

There is a piece called a crankshaft reluctor ring? Something like that. Sits right in front of the gear on the crank. Without this piece, the crank sensor has nothing to read and therefore will send the signal for no fire.

Try contacting 961500 for the part number. We replaced his engine and spent a week trying to figure out why it wouldn't fire. Turned out this piece was left off. reinstalled a new one, and it fired right up.

I know it just didnt feel right when we put it in, because it just slides over the shaft and hangs there until everything is snugged up.

 

[Mild]

lot of miles. how did it run before that?

just curious because mine is sitting on 239. its a 99 as well.

 

[TechGirl]

Verified the crankshaft reluctor ring was in place.
It still wont start.

I am so frustrated now.

My last resort is to tow it to the dealership.


What makes me so sad is the truck was running fine - no problems, no issues. It wasnt smoking or using a lot of oil or any issues that most vehicles have with high miles on the original engine. I let a guy convince me to replace the time chain for "maintenance" since my truck had so many miles and I travel every weekend.

HELP!

 

[hapyspaz]

During and after cranking, has you check engine light set a code?

When we did 961500's engine, he ha a crank senor code setting, turned out the wiring harness (pigtail) to the sensor was bad and we had to hold it at a certain angle to get the engine to start and stay running.

Could be wiring and/or the sensor itself. If nothing else was done, thats the only other thing I can think would be an issue. If the crank sensor isnt sending a good signal, the engine will not start up.

As long as you are getting fuel the crank sensor may be the issue. Sounds stupid, but make sure it is plugged in...

 

[994door]

does it have spark or fuel pressure?

 

[TechGirl]

Thank you all for your responses.

YIPPIE!!!!!
I finally got it started.

The code kept saying crank sensor. So I replaced it - twice as a matter of fact.

The WIRING HARNESS was the issue. There was a short.
Replaced it - and it cranked.

THANK YOU ALL!!!!

I'm not a real mechanic, but I try to do what I can to fix my own truck.

With 340,000 miles on the original engine, I think I'm doing pretty good.

Again, Thanks so much.

 

[ravingmadman]

Outstanding. I hate it when that happens. you make one change, and then something completely unrelated goes wrong, and you chase your tail for hours, trying to prove you aren't on crack...