OddyseusDSM

Vats is flashing, power to injectors, power to coil, all computer powr wires connected, all grounds connected as far as I know. It cranks, fuel is still an issue but I can manually run the pump so it shouldnt matter. Followed LT1 for dummies and numorous other swap pages and I'm still not getting it to kick over, its like the injectors and the coil arent getting power even though I verified they are.

This is a '96 engine into a '92 TBI Camaro, I need it to start and drive so I can get it to paint, I can tidy up everything later. Is there anyone in the area willing to check it out cause I'm stumped.

-Mike

Firebat

iTrader: (7)

Vats is flashing? Explain.

OddyseusDSM

The vats decoder module is supposed to flash when connected to an appropriate power source, it is also connected to the fuel enable feed.

Firebat

iTrader: (7)

So its an aftermarket part/box that gets rid of vats, right?

OddyseusDSM

Yes, I've seen a few users who've gotten good results using this. Would VATS disable spark and injectors do you think, I thought it was only a fuel cut feature for the pump.


http://cgi.ebay.com/ebaymotors/GM-VA...84192247QQrdZ1

^^I got the dual O2 sim with the VATS bypass from these folks, recommened specifically by a few others.

Only meant to be temperary while we get the car running.

Firebat

iTrader: (7)

With Vats, the car will start then run for about a second or two and then shut off. It shuts off more than just power to the fuel pump.

OddyseusDSM

Well the computer supplies the ground for controlling the injectors and coild right? Could the computer be bad?

Firebat

iTrader: (7)

I don't rembember how the computer controls the injectors and coil. A bad pcm(computer) would cause the engine not to run. A pcm usually goes bad during a programming error.

Spark plug wires hooked up wrong could also be a cause. Also, the optispark connector not hooked up or the coil not hooked up.

OddyseusDSM

Plug wires are right, plug to the opti is in, new crank sensor, still no spark. All main grounds are on. Keyed source to injectors and coil are 12 getting power even when cranking.

Thirim

running 96 computer? .. IE OBDII? or OBDI ? ... check 12 volts supply to computer.. i think there are 2 or 3 12v feeds... also tripple check grounding.. when you say no spark.. u mean nothing out of the coil? .. coil is grounded right?

OddyseusDSM

OBDII, yes I'll double check the supplies and grounds. Also the coil is grounded in the same fasion as 4th gens

Firebat

iTrader: (7)

Try these tests. You'll need a multimeter. A cheap one should cost $10-20.

Prove optispark signals are getting to the coil: http://shbox.com/1/4th_gen_tech2.html#opti_test

Coil Continuity Test: http://shbox.com/1/coil_testing.jpg

OddyseusDSM

The wires were not in the same order as the diagram but worked out right if you just align the ABCD......yeah. but anyway Im getting power there but none when cranking so I'm gonna grab an Opti. YAY!!! And the W/P comes off again, I'll look into a Buick one this time maybe that will fit better than the Corvette one (heater lines). Anyone have any opposition to an Autozone special Opti? I work there so I get a discount and it should work for now, I just want it to start today.

Someone wanna explain where their fuel pump relay tapped into? I'm using the origional relay, but I bypassed it to wire the thing to run and havent found any definitive answers. orange to battery, the grey already runs to the C100 but i left another grey out which I used to bypass, black to ground, but where does the prime wire run too and the grey one on the origional......?

Klortho

The grey one should go to either the blue or white connector (don't remember off hand) and is the fuel enable wire that is green/white which should be a green/white coming off of the original relay.

cam-

Twice now... I have been foiled by seized injectors. once on my players TPI motor and just recently again on my LS1

Same ***** as you.. Fuel pressure was good, I have light testers for the injectors and they were firing, had good spark yet no start!

So I sprayed fuel directly into the throttle body while my buddy cranked and it started so I was triple confused. After three tries of this I managed to get it started on one cyl. Sounded BRUTAL but it ran.

A few taps with a long 3/8" extension on each injector and it was running on four. After tapping ( on the shafts ) rigorously on all the rest it started running on all eight. Worked for em so you never know if its been sitting a while this could be it. Good luck!

RAGEman

I'm having a very similar problem with mine. It cranks and hits but it never quite starts. I pulled the fuel rail and cranked it, each injector pulsed as it should, I have replaced my opti twice, and It still doesnt work. I also have an MSD cap and rotor, but i heard that they were having problems with the rotors rubbing or something, so I think Im going to buy a new completely assembled opti and try again. I have checked plug wires, grounds, and PCM power wires and all are good. I have a Baker Electronics VATS bypass module, and I have a Painless wiring haness. If you figure out the problem, please let me know what you did.

USAFCC

I am having a vats promblem and am trying to locate the decoder module. It started off by doing the same thing and after much troubleshooting i found a wire at the connection under the steering column that goes to the decoder is showing about 6.4ohms when my key shows 3. so i am trying to find the decoder to see if the wire is bad....

1984camarooo

i am doing an lt1 swap from a 1994 camaro into an 1984 camaro, i have the wiring harness from the 1994 camaro but cannot get power to the computer. Does anybody know what the power wires are

Thirim

pm sent for email... -edit, email sent with wiring pics
but to answer your question, B15 and B31 on the ecu.