caweisel

Driving home and car quit, has not restarted since. New Fuel Pump
(What Fun), new plugs, wires, rotor, cap and module. Still won't start. Fuel pump is working but car gets no fuel. If I spray gas into the Throttle body it starts right up but immediately dies. I purged the fuel line up to the fuel rails but the car still cranks but wont start.

New injectors last year so virtually everything is new and in great shape.

Any advice would be appreciated. Could the VATS be causing the problem. The owners manual says that if the VATS is on the car won't start but it doesn't say if it will turn over. I wondering about a VATS malfunction. I would like to bypass it, if that is causing the problem.

When the ignition key is turned on the security light comes on then goes out after about 5 seconds...

Help

Dave89IROC

VATS sound Ok

check for codes, and check for power at the injector plugs with the key on

caweisel

Thanks for the info about my IROC. I have checked the fuses for the injectors and they are okay but is there any relays that you know of the power down all the injectors. It was starting and running fine then suddenly just quit. I have relaced everythin and the car is still not responding so I must be missing something.
Thanks so much for you help...nice to hear from someone who is knowledgeable rather than a kid with wire cutters and a hammer.
Charles

Injuneer

With your 3rd Gen, you will probably get better result on the "3rd Gen/L98 Engine Tech" forum. "LT1/LT4 Engine Tech" covers the engines used in the 93-97 4th Gens. I'll move this to "3rd Gen...." for you.

Rice Killer87

How many miles are on the car?

Could be a fuel pressure regulator but its hard to tell. Is it gettin fuel at the shrader valve on the fuel rail?

Take a plug wire off and stick a regular (straight) screw driver in it and then hold it close to ground and turn the car over to see if you get spark.


Hope this helps

Black305RS

i think it could be the vats or rather the key. i had a 91 firebird that suddenly quit on my one day and wouldnt restart. it cranked but wouldnt start. i wiped the key off and tried again and it started. this happened twice. the guy i boyught the car from said that one of the keys he had made caused this for him to and that i should use one of the other keys.

Dave89IROC

If it was vats input(key) problem, it wouldn't crank, unless the theft deterrant relay was bypassed

Black305RS

the 91 i had was not bypassed. it so stock it was sickening. i also talked to a tech at gm and he said that it would crank but the injectors just wouldnt fire.

89Vert

I had my VATS fail, it wouldn't crank

89Vert

do you have spark while cranking?

88IROCTPI

i will have to check my books to see for sure on the TPI engines but i do know for a fact that the injectors on a TBI engine recieves its signal from the coil. both TPI and TBI systems use the same coil and a good aftermarket coil will cost less than 50 bucks or a stock one less than 25 bucks. That would be my educated guess, a coil. That is about the only thing you havent replaced and it would cause it to still start when shooting ether down the intake.

89Vert

I'd say more likely it would be the ignition module then the coil,
if spark is the problem

88IROCTPI

spark doesnt seem to be the problem if the car tried to start off of something being sprayed in the throttle body, and if the car has fuel pressure and the fuelrail then it has pressure at the injectors, so if fuel pressure is good and it has spark then we need to find out why the injectors are not getting a signal to open. I do not know if these TPI motors are equipped with a crank or cam position sensor, but i dont think they are, and that tells me that the only other place that the injectors could recieve a signal to open from would be a coil.

Rice Killer87

No cam or crank position sensor.

The ECM provides the ground for the injectors which tells them when to fire. TPI is a "batch fire" type of fuel injection meaning all of the injectors are fired at once.

90rocz

Here's what happened to me:
Occasional trouble starting, at first, then one day I went out and...nothing.
Ended up being the magnet in the distributor was cracked all to h3LL. I found it by swapping the distributor out of my '88 Suburban, and it fired up. I got a new distributor with module, from Advance Auto parts for $99.00.