Intermittant no start-NO CEL

[ssenter]

1994 ATX w/ 120K. It has an intermittent crank but no start issue. NO Check engine light! First time, waited about two minutes after fueling and refired. Second time, died while taking a corner fast, and refired immediately. Third time, went into store to get soda, came back out and wouldn't fire. Tried for about 15 minutes to start, and had it towed to shop. Of course, fired right up later.

Tonight, 1st day after picking up from shop, it wouldn't start after sitting a couple hours. Fuel pump ran when I tried tonight to start! I got out, pushed up/down vigorously on rear bumper, and it fired immediately. I'm open to suggestions on where to check, I'm thinking a loose/intermittent electrical connection, but no idea where to start!

BTW, I tried search function for "no start" but got an error message, and reported it in a separate post. Thanks so much for your help!
Scott
Klamath Falls, OR

 

[jimtash]

Crank or cam sensors are acting up when they get hot.

In simple terms, crank sensor controls the spark and timing. Cam controls the fuel injectors.

 

[rubydist]

just because the cel is not on does not mean there are no codes - you need to check for codes. if there are codes, it will give you good guidance on what to fix, otherwise you will just be guessing.

with your symptoms, you could have several problems, including iac, fuel pump, crank sensor, etc.

with respect to jimtash's post above, if the tach works fine then you do not have a cam sensor problem. if the tach reading is erratic or non-existent, then you likely have a cam sensor issue. all the cam sensor really does is to tell the pcm when #1 cylinder is at tdc and run the tach.

 

[ssenter]

Tach works fine; I'll see if shop pulled codes, if not I'll do it and report back in a few days (still have my taxes to do!)
Scott

 

[ssenter]

Update on no start issue. SHO has quit suddenly twice, like ignition turned off. Second time I went back to try a restart after about 2 hours and it did restart. Mechanic says NO codes were pulled up, and NO check engine light. He believes it may be the ECM module AS no codes were set, and no sputtering of engine prior to shutting off. I hope to get it to the shop and have it not restart there! Anyone else have ECM issues?
Thanks
Scott

 

[rubydist]

based on your symptoms, ccrm, pcm, and crank sensor would be suspect, in that order.