intermittent electrical/sensor/VCM problem?
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From: Phoenix, AZ USA
intermittent electrical/sensor/VCM problem? the '01 Z28.......
Sunday, Monday, and Tuesday afternoon the car was firing right up and ran like clockwork (idles by itself, air/fuel is right on 14.7 all the time unless in PE then 13.0, and overall pulls like it has a rocket strapped to it....). I drove around Tuesday night for a few hours (fill up with gas, went to dinner, etc...). When I got home I pulled in the driveway and shut it down (didn't touch a thing).
Wednesday morning I went out to go to work and the engine just turns over but never lights off (it gets a "pop" now and then like the spark is coming on the exhaust stroke/wrong time). I pulled out the scanner and there are no codes, all the sensors (MAP, TPS, coolant temp, etc.....(no MAF...running SD)...) all seem to be working, I have fuel getting to the cylinders, and I have spark (pulled a plug and watched the spark jump the gap). Everything seems to be working but yet it will not fire up.
So in the 10 hours I slept from Tuesday night till Wednesday morning the car decided it does not want to fire up anymore. WTF?
I had this start happening a few weeks ago (exactly same type of thing) so I changed the Cam Position sensor (since it sounded like it was out of phase but I am getting a Tach signal which I don't think I would get if the Crank sensor were out/bad) and after a bit or cranking with the plugs out it fired up. But then the next week I had the exact same thing happen again so I again replaced the Cam sensor (figured I could have got a bad replacement) and again it "fixed" the problem but now the problem is back.
So WTF do I start looking at now? What could just decide to not work like that?
Sunday, Monday, and Tuesday afternoon the car was firing right up and ran like clockwork (idles by itself, air/fuel is right on 14.7 all the time unless in PE then 13.0, and overall pulls like it has a rocket strapped to it....). I drove around Tuesday night for a few hours (fill up with gas, went to dinner, etc...). When I got home I pulled in the driveway and shut it down (didn't touch a thing).
Wednesday morning I went out to go to work and the engine just turns over but never lights off (it gets a "pop" now and then like the spark is coming on the exhaust stroke/wrong time). I pulled out the scanner and there are no codes, all the sensors (MAP, TPS, coolant temp, etc.....(no MAF...running SD)...) all seem to be working, I have fuel getting to the cylinders, and I have spark (pulled a plug and watched the spark jump the gap). Everything seems to be working but yet it will not fire up.
So in the 10 hours I slept from Tuesday night till Wednesday morning the car decided it does not want to fire up anymore. WTF?
I had this start happening a few weeks ago (exactly same type of thing) so I changed the Cam Position sensor (since it sounded like it was out of phase but I am getting a Tach signal which I don't think I would get if the Crank sensor were out/bad) and after a bit or cranking with the plugs out it fired up. But then the next week I had the exact same thing happen again so I again replaced the Cam sensor (figured I could have got a bad replacement) and again it "fixed" the problem but now the problem is back.
So WTF do I start looking at now? What could just decide to not work like that?
Last edited by 2001CamaroGuy; Jun 16, 2005 at 10:21 AM.
