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GTWC won't start (fuel injectors no worky?)


Foghorn37
05-10-2012, 09:10 AM
I had to remove the engine (full story over a cold beer - those with the quartermaster clutches beware).

Reinstalled engine, everything is plugged in, car won't start.

pulled a plug, getting spark. plugs are dry, hence I don't think the injectors are working.

I am getting power to the injectors (my DMM shows 11 volts).

fuel pump is working (PI says 33 psi with the switch on). fuel pump runs continuously, though. I thought is was supposed to quit after a few seconds - electric fan runs continuously, too.

I have checked and cleaned both engine grounds - I have a negative battery cable on the passenger side from engine block to frame & a traditional ground strap from the driver's side motor mount to the frame.

Will the fuel pump relay being stuck prevent the injectors from firing? I don't understand why the electric fan is running continuously either....

Foghorn37
05-11-2012, 12:50 AM
After many google searches, I think the problem lies in the CCRM - which is the multiple relay black box that controls the A/C (not applicable), the fuel pump, the cooling fan, and the PCM.

I found a test procedure online and my CCRM didn't pass one of the parameters. I would like to know if there is a way to bypass it with a couple of jumper wires prior to dropping $200 on a replacement.

Foghorn37
05-21-2012, 04:06 PM
changed ccrm, still no start condition.

bought an OBD-2 scanner to see if the PCM will tell me anything. Scanner won't connect....
it's getting power to the OBD port, but other than that I don't know what to look for. The wire bundle traces back to the ignition switch "box".


PATS tripped? Any suggestions?

PanozDuke
05-22-2012, 06:16 PM
changed ccrm, still no start condition.

bought an OBD-2 scanner to see if the PCM will tell me anything. Scanner won't connect....
it's getting power to the OBD port, but other than that I don't know what to look for. The wire bundle traces back to the ignition switch "box".


PATS tripped? Any suggestions?

I'm no expert on the 4.6 EFI system, but after reinstalling my EFI 5.0 based stroker, I had no fuel injectors firing (you can hear them during cranking) and it wouldn't hit a lick. Checked all the physical ground connections and they were tight and from block to frame I had zero ohms. Figfured I was good. That turned out not to be the case.

There was a small ground in the engine/ fuel injector harness that connected directly to the upper frame rail at the cross brace location on the passenger side, next to the alternator. It was tight but a check between the wire eyelet and the cross brace showed a few ohms (I think it was about 30). I took the wire loose, cleaned the surfaces and hooked it up, got zero ohms and the injectors fired on cranking and it started.

Hope my three days of head banging helps you avoid something similar.

Mike

btwog
05-24-2012, 03:52 PM
changed ccrm, still no start condition.

bought an OBD-2 scanner to see if the PCM will tell me anything. Scanner won't connect....
it's getting power to the OBD port, but other than that I don't know what to look for. The wire bundle traces back to the ignition switch "box".


PATS tripped? Any suggestions?

Try posting in the SVT/DOHC forum over at corral.net. I'll bet someone has seen this before.

Foghorn37
05-28-2012, 08:40 PM
Mike - Thanks for the tip. Unbolted the engine bay ground on the right side upper frame rail and cleaned the shit out of all the ring terminals and the grounding stud. Went the the back of the car next to the battery and did the same there. No change [bummer]...

Removed the Diablo chip from the expansion port on the PCM thinking that it may have crapped out. No effect [bummer]...

Did a local CL search and found a guy who was parting out a 98 Cobra convertible. Bought the PCM from him. Thought about getting the key, but convinced myself that the PATS logic was in the little black box associated with the column harness vice in the PCM.

Switched "new" PCM with "old and suspected faulty" PCM. Flipped the switch - the cooling fan didn't come on instantly and the fuel pump cycled as advertised. Hit the starter and she fired right up....

....for about 2 seconds [bummer]. Seems like a PATS issue.

I think I can solve the PATS issue with a tuner (which it needs anyway), 'cause I don't want to spend 4 hours on the road to go get the key.

*UPDATE 31 May*

Able to get the key from the parts car. Doesn't solve the problem. I guess I am off to the local dealer to reprogram the PATS.

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