sweetC5

Here's the run down, rebuilt ls1 with a small cam, fresh trans and 3000 stall. All wiring and grounds hooked up, engine cranks but will not start!! Won't even make a pop, seems like no spark or fuel. We have no codes but the check engine is on. We did have a crank position sensor code at first but we fixed it, code has not come back in days. We ran threw all the wiring and grounds again today and tried another computer with no luck still!!!

sweetC5

99 trans am, I also check the pink wire to the coil pack and we are getting power.

Mgg4591

iTrader: (3)

Did you check for fuel pressure at the fuel rail? Also you can listen with a screw driver or stethoscope to see if the injectors are firing while cranking.

sweetC5

Yes the fuel rail definetly has fuel pressure. But I don't smell gas after cranking the engine, so not sure they are even firing. Can VATS be an issue?

gMAG

iTrader: (1)

Yes, VATS can be an issue. There have been instances where a program will show that VATS is off, when it is actually on.
Before you go that way (maybe you have no way of checking this), I would check the injectors with a noid light, and verify that they are "firing". Firing, and the actual opening, are two different things. Depending on how long the injectors had been unused, may cause them to gum up, so even though they are "firing", there may be little or no gas flowing through them.

sweetC5

Thanks, I will get a noid light tomorrow and check the injectors! Getting very frustrated

gMAG

iTrader: (1)

AutoZone has a noid lamp set for "rent". If you're not familiar, you would pay for the set up front, then, when you return it, you get your money back.

slogo

can you use starting fluid on these engines safely?

sweetC5

Checked with noid light, we have no pulse! Replaced cam sensor and it did nothing, still have no codes either.

5.0 LsX

iTrader: (7)

map/cam sensors in back all plugged in, no bent contacts?

Exeodus

iTrader: (1)

Have you checked the ignition relay?

sweetC5

Swapped ignition relay, bypasses VATS, nothing! My scanner is not picking up rpm during crank. But I have tried two sensors and rewired half off it with a new connector. Reluctor wheel is stock and I can feel it there with my finger. Still no codes, no fuel, this is fu$king stupid!!!

sweetC5

Pulled intake off again and wires seem fine, all is plugged in and have power going to them. Grounds seem to be fine as well.

sweetC5

Here's a funny one. I pulled the plug off the crank sensor, guess what, no code. Does that make sense if te engine never ran?

Mgg4591

iTrader: (3)

Have you checked the pcm grounds? Im not sure where they are on 4th gens, but for my swap i have one ground on the back of the driver rear cylinder head, and one under the dash near where i mounted the pcm itself. The ground under my dash wasn't making good contact, so my obd2 port wouldn't connect and the car wouldn't start some times. Just something else you can rule out.

sweetC5

As for grounds, I have 3 coming off the harness going into the driver cyl head. I have 3 down by the alt, one going to te alt, one frame, one on the block. Then I have the battery ground, one on the block and one to the battery, also added a ground strap engine to body!!! I checked all off them and made sure no paint or anything. Totally lost guys!!!

Hardcoresoldier

iTrader: (2)

do NOT use starting fluid unless you want a lot more problems to deal with...

Your scanner is not showing engine RPM when cranking. If this is the case, the computer does not know the engine is turning so it will not fire the injectors or the plugs.

gMAG

iTrader: (1)

When you said, "bypasses VATS", does this mean that VATS has been verified as turned off, or did this mean that you have a VATS bypass module?

sweetC5

I bypassed VATS by unplugging it and using the correct resistor by the ohm of the key. Car still cranked the same. Yes my scanner is not picking up RPM during crank. I also have not sprayed starting fluid! We have picked up a new plug for the crank sensor and wired that in, tried the stock sensor and the one we got from autozone and nothing. I do have 12v to the sensor but that all I know.

gMAG

iTrader: (1)

I don't mean to pester you, but what does unplugging VATS, mean?
Did this mean that the BCM module is unplugged?
VATS needs either to be disabled, or, the VATS signal needs to be constant, like a VATS module.
Maybe the later F-bodies operate using a different system?