No start - Injectors won't fire

sdw

Registered User
My '91 5-speed died when going over a speed bump.

I have looked for a connector that came apart but have found nothing. I have spark, and fuel but the noid light did not flash when I checked the injectors.

I changed the crank sensor to one of my spares but no change. Changed the IRCM to a known good one, no change.

The car is modified and has a BHJ balancer and a QH chip, etc, etc.

I am not sure where to look now.

My grounds are good including the the one at the back of the drivers side head.

Is there a way to test the EEC?

There is one connector under the car attached to the transmission support that is melted from where it must have hit the exhaust. But the EVTM and wiring diagram has no info on it. My EVTM is at my garage so I can't give the page number but if you find where the two connectors go into the transmission you will see it pictured attached to the tranny support bracket. The connector has an end plug on it, but I have no idea what it is for.

Any suggestions would be appreciated.

Sean
 

sam jones

Registered User
Good afternoon

Try this. Open the trunk. On the driver side check for the (red button) inertia switch in the open position. If it is reset (push down).
 

sdw

Registered User
Thank for your reply.

Inertia switch is closed. Fuel pump comes on and delivers 40lbs to the rail.

I had installed a remote cutoff switch at the inertia switch as my car had been stolen but that has been removed for now and the wiring is returned to stock.

Sean
 

sam jones

Registered User
Good evening

Inertia switch good- check.

With the key on is the fuel pump constantly running (priming) with engine check and upshift arrow lights on?

Check the ignition switch for separation and the connector pins for security.

Check the DIS harness. Visual inspection will be twisted, frayed and exposed wiring. Remove from car. With the EVTM ohms checks the following connectors potentially causing intermittent electrical outputs.

CAM connector to DIS gray/black connectors.

CRANK connector to DIS gray/black connectors.

.
 

MadMikeyL

SCCoA Member
Do you have a chip, or the actual quarter horse in the computer? If it is the quarter horse, I have had the battery go bad before and prevent the car from starting, so you might want to try removing that from the ECM and seeing if it will start without it.
 

Tim Groth

SCCoA Member
Expanding on bad QH battery. Usually with key in the forward position the fans will run on high which is also a tell.

-Tim
 

sdw

Registered User
I had the QH swapped over to the replaceable battery one.

I will pop it off the EEC and see what happens.

I hadn't thought it would have thought it would have lost it's charge already but I have spares so will replace it nonetheless. The car was running when it died so I am pretty sure it isn't a QH battery issue, but better to change it and be sure.

tks

Sean
 

sdw

Registered User
Went through the evtm and wiring diagram to track down all the connectors.

The PIP is working and there is no resistance on pins 56 and 16 to pins 1 and 3 respectively.

I cut out my melted connector from beside the transmission to clean that up but I can't imagine it has anything to do with the no start issue.

Here is a picture of the connector, sorry for the quality. if anyone knows what it is for that would be great.

Is there a way to test the EEC?

Regards

Sean
 

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sam jones

Registered User
Good morning

You can do a Key On Engine Off scan quick test. If you get 11/111 the EEC should be good. Correct any other fault codes. You could remove the EEC and do a physical inspection. Disassemble and look for corrosion, bad solder or overheated capacitors. Does your tuning chip cause a leg of the capacitor to be compromised? Inclosed is a short subject and although it is mustang directed it (EEC IV capacitors inspection) applies to the super coupe.

 

sdw

Registered User
Thanks for the reply.

I did a KOEO test and got 111. There were no other fault codes but as the battery got discharged any stored codes are gone.

I will have a look at the circuit board and see what it looks like.

Sean
 
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