I just swapped in a 3100 and when I turn the key on the fuel pump primes up, car starts for a few seconds then shuts off... I got to thinking about it and the 3100 has a safety feature to cut the fuel pump when something with the oil isnt right, i believe its the oil level if i remember correctly.

My question is did my 95 2.2 auto 3 speed have this same feature, and since im not using the cavy harness, its not seeing an oil pressure and killing the fuel pump?

SOUNDS LIKE VATS TO ME.

do you have a security light on the dash? Is is blinking or staying on??

I dont believe my car has VATS... I have never seen a theft light on my dash, NEVER...

what year of 3100 PCM are you running its deffinatly sounds like VATS, doesn't matter if your car had VATS swapping in a 3100 you my have added VATS to the car we need to know the year of PCM and what it came from

its likly not an oil pressure issue unless your wiring is messed up

you shouldn't have touched the oil pressure wires

it has to be the theft





JBO since July 30, 2001

ECU came out of a 94 pontiac grand am SE, Hopefully its not a VATS issue, I havent any clue how I would go about fixing that since The engine harness doesnt really go into the body harness except for a few ignition wires..

I cant find anywhere that says that ecu has VATS... this is annoying, I just want to drive my v6 lol

did the grand am have a chip in the key?



my kill list:a geo metro and a mac semi wow did i kill that thing

what ecu is running the fuel pump relay???

Ok, no the grand am key didnt have a chip, and the cavy ecu is running the fuel pump relay... which is why i think its not running, just priming..


- Your not-so-local, untrained, uncertified, backyard mechanic. But my @!#$ runs

So nobody knows about any safety feature on my cav ecu to cut fuel?


- Your not-so-local, untrained, uncertified, backyard mechanic. But my @!#$ runs

I believe the oil pressure switch was the safety device, shutting down the ignition module. However I dont think thats your problem.
I dont think you should be using the cav ecm for the fuel pump relay. The reason that I say this is because the cav ecm looks for a crank pulse in order to switch from priming to cranking/run fuel. No crank pulse no fuel enable signal. What your actually doing is priming the fuel system with each key cycle, when you try to start it you are using up the fuel in the rail till you run out. when you cycle the key again from off to on it primes the pump again. See where Im going here. Hook the relay enable to the 3100 ecm and let us know what happens.



01 cav w/01 3400 gam gt 4t45e

I got it running now... Sounds good runs strong..


- Your not-so-local, untrained, uncertified, backyard mechanic. But my @!#$ runs

So what was wrong?


01 cav w/01 3400 gam gt 4t45e

Its the crank pulse thing you mentioned above... Cavy ecu didnt see the crank pulse because there wasnt one, I just bypassed the relay to the ignition.. so if the key is on, the fuel pumpp is running, I dont like it that way, but it runs..


- Your not-so-local, untrained, uncertified, backyard mechanic. But my @!#$ runs

Wait..... are you running the Cav ECU in addition to the V6 ECU?
If so, why is the Cav ECU running the fuel pump?

The cav ecu is being used for the gauges only.... thats it... I tried to stay away from changing the factory wiring as much as i could...


- Your not-so-local, untrained, uncertified, backyard mechanic. But my @!#$ runs