Vette will not run
Thread Starter
Team Owner
Joined: Feb 2006
Posts: 24,460
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From: sw Ohio
Vette will not run
I need help, my Vette will start but wont run. All I did was change the valve cover gaskets. I've checked everything: spark plugs, wires, vacuum lines. Its getting everything it needs, so why wont it stay running???
Thread Starter
Team Owner
Joined: Feb 2006
Posts: 24,460
Likes: 7
From: sw Ohio
I reconnected everything that I disconnected. I checked all the spark plug wires to make sure they're in the right places. I dont know what an EST is. I dont know exactly how to check codes.
Le Mans Master
Joined: Feb 2006
Posts: 8,753
Likes: 9
From: Louisiana
Originally Posted by 4Ever21
I reconnected everything that I disconnected. I checked all the spark plug wires to make sure they're in the right places. I dont know what an EST is. I dont know exactly how to check codes.
Last edited by RRT vette; Apr 2, 2006 at 02:27 PM.
Melting Slicks
Joined: Jan 2005
Posts: 2,658
Likes: 4
From: Clifton Park NY
Did you knock off any sensor wires?
When I did my valve covers gaskets I disturbed the fuel pump relay connection. It looked connected but then I push on it a little and what do you know it went on a bit further then started right up
When I did my valve covers gaskets I disturbed the fuel pump relay connection. It looked connected but then I push on it a little and what do you know it went on a bit further then started right up
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Le Mans Master
Joined: Feb 2006
Posts: 8,753
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From: Louisiana
Originally Posted by AGENT 86
Checked injector connectors too 
If you loosened any injector connections this would make it run as you described. If you didn't disconnect the battery before hand, you might have shorted a wire and blown a fuse. I would visually check these and might even test light both sides on the fuse. Just a hint.
Thread Starter
Team Owner
Joined: Feb 2006
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From: sw Ohio
Yeah that makes sense, I never checked the fuse box even though I disconnected the battery. Is there any way that anything could have gone bad by replacing the valve covers? I checked all the injector connections they're good. Of all the cars i've worked on, this one has stumped me everytime I work on it. I'll check the fuse box and some of the wiring too. Thanks guys.
Le Mans Master
Joined: Oct 2003
Posts: 6,130
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From: seattle WA
Just changing valve cover gaskets ain't gonna make it worse than before, re-check those injector pigails, make sure there on good, there's also alot of vacumn lines in that area-check to make sure there's none disconnected or leaking! And check all electrical connections-AGAIN.
Thread Starter
Team Owner
Joined: Feb 2006
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From: sw Ohio
Using the A-B pin method of checking codes I came up with these results: Code 12 flashed 3 times, followed by this flash (pause) flash 5 times in a row. It repeated that one 3 times like you guys said it would, followed by the code 12. I dont know how to tell what code this is, could you help? please??
Le Mans Master
Joined: Feb 2006
Posts: 8,753
Likes: 9
From: Louisiana
Originally Posted by 4Ever21
Using the A-B pin method of checking codes I came up with these results: Code 12 flashed 3 times, followed by this flash (pause) flash 5 times in a row. It repeated that one 3 times like you guys said it would, followed by the code 12. I dont know how to tell what code this is, could you help? please??
After inserting a paperclip or what ever into the ALCL the check engine light will flash once- pause -two flashes bach to back (code 12). This will happen 3 times as you stated. The next set of flashes will be the code. Say if a code 33, there will be 3 flashes back to back - pause - 3 more flashes back to back. And this will repeat 3 times as did the code 12. If there is another code stored it will be a different set of flashes and so forth. When all the codes have appeared it will flash a code 12 again. If there is a code let us know and we can help you troublshoot. As you said it flashed 5 times, make sure there is a pause in between. This could be a code 23 or 32.
Thread Starter
Team Owner
Joined: Feb 2006
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From: sw Ohio
I understand now, its a code 15. However I highly doubt a low coolant reading from the sensor would cause it to not start. It started raining really bad here, so it'll have to wait until tomorrow. I might get new vacuum tubes tomorrow to see if that fixes it.
Team Owner
Joined: Jan 2003
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From: Summerland B.C. Canada
Originally Posted by 4Ever21
I understand now, its a code 15. However I highly doubt a low coolant reading from the sensor would cause it to not start. It started raining really bad here, so it'll have to wait until tomorrow. I might get new vacuum tubes tomorrow to see if that fixes it.
http://members.shaw.ca/corvette86/Code%2015.pdf
The ecm could be fooled into thinking it's -50 and adding more fuel, thereby flooding the motor. Just a thought
Drifting
Joined: Mar 2005
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From: GA
If the CTS connector is good. disconnect the battery again for a minute and reconnect. Start the car and keep it running as best you can. Shut down when the check eng light comes on or after a minute or 2. check for codes again. If that code 15 is back, replace the coolant temp sensor. They cost about $7 at Advance auto. If the code 15 isn't back and the car still runs like before, start looking for a big vacuum leak.
Thread Starter
Team Owner
Joined: Feb 2006
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From: sw Ohio
I tried it again this morning. I checked all the fuses, they're good. The fuel pump is good and giving plenty of fuel. Rechecked all hoses, lines, etc. I took the gas cap off, put it back on and tried that (my dad's idea). Still wont start and still getting code 15. Checking coolant sensor....
alright, the sensor was unplugged. I plugged it in, code 15 is gone. But it STILL wont start.
alright, the sensor was unplugged. I plugged it in, code 15 is gone. But it STILL wont start.
Last edited by Demonic85; Apr 3, 2006 at 11:54 AM.
Le Mans Master
Joined: Feb 2006
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From: Louisiana
Originally Posted by 4Ever21
yes it will keep running until i let off the gas, but it backfires and misses horribly while giving it gas.
I am still wondering about timing here. This sounds like when my car was out of time. I know that changing valve cover gaskets doesn't have anything to do with the timing, but. Well also see if you disturbed the TPS sensor on the right side of the Throttle body. Check all the connections on and around the TB. Also check to see if the MAF sensor is connected. These will show codes if there is anything wrong, but it does take a minute or so of run time for them to usually show up.
Melting Slicks
Joined: Feb 2002
Posts: 2,699
Likes: 2
From: The Black Hole LA
Originally Posted by 4Ever21
But it STILL wont start.
Clarify this. Will the engine turn over? If so does it sound like it is trying to fire, just won't "catch", or is the engine just turning over with no signs of firing, ie popping/backfiring. Or does it start but die without the throttle pressed like you said before when you said you could keep it running by pressing the gas?