I'm having an issue with my ls1, I put into a 1967 camaro. When I go to start the motor it will run for anywhere between 5 seconds and 25 seconds and shutter off. Similar to a vac leak, and I dont think there is one. I also notice that I am not able to rev the motor.


my thoughts,
I dont have the iat installed yet, nor the o2 sensors as im still building an intake and the wires on the 02 sensors are not long enough. But it still seems the motor should be able to run without them.


thanks in advance for any help!

 

Any ideas or is it a must that these are connected?

 

Could it be the computer anti theft feature? my friends did the same thing until he sent out the pcm to remove the anti theft feature.

 

Yeah could be vats!!where they program out of computer?

 

Sounds like the VATS needs to be deleted from the ECU...what they said...

 

The computer went out to Wait4meperformance, So I called him today and he said it's deleted. There are no codes in the ecm, i even unplugged the maf just to make sure the computer was reading codes and got a code for it. Guess i will have to send it back to him to check and see if vats is gone.

eveytime I restart the motor it runs and shuts right back off....


thanks guys...

 

Every swap that I encountered, that had the same issue, had to have the ECU, re done...

 

Typically vats will cause it to stall almost right away. Not 25 seconds later. I recommend that you hook everything up and then try starting it. The IAT is essential for fueling. O2s not so much, but still, get everything hooked up.

Jon
PSI

 

Thanks for the suggestions, I'm boxing the computer as we speak... I wrong on 25 sec more like 8 to 10 max.... Just tried to start again and recount. Will update when I get it
Back from them.

 

Keep us posted.

 

Before the ECM is sent back, did you connect the IAC?
An alternative to deleting the VATS is to buy a signal generator for $25 from ebay. It will simulate the signal that the BCM sends to the ECM to enable fuel delivery. This generator can be installed with a hidden switch, so that you'll have some sort of anti-theft in your car. Just a thought.

 

I didnt read this before the computer was in the mail.... But i have an external fuel pump with a hot line. I did check and the iac is connected. Also i was not getting any codes showing issues either though. i have a 98 camaro ecm so i heard it will stop the injectors and spark when vats enables....

 

Have you checked the fuel pressure at the rails? Mine would idle great but wouldn't rev and then would sputter and die. Turns out fuel pressure was down. Corrected FP problem and has been running perfectly since.

 

that i didnt... i dont have a guage... will go buy one as soon as i get the computer back and it fails to fix the issues.... Wha did you do to fix the fuel pressure issue?

 

what did the issue end up being?? was it the tune that had to be redone?

 

im having a similar problem with my car did you get this figured out ?

 

I'm in the same boat. I had my VATS removed and my car still won't start. Any tips!? It cranks but dies after 3 seconds. Help

 

If the VATS has been deleted I would look to the fuel pressure in each of the above cases. The pump for a throttle body looks just like a multi-port pump. In any case, new tools are in order. Get a fuel pressure gauge that hooks to the schrader valve and also get a 'noid light. These will help you determine what is shutting down.

 

Figured out my error. Had a bad constant power to my ignition switch. Fired her up today!