HELP!!! No start and can't find the problem??

[vp6799]

I have a friends car at the shop and it's been a real big pain...

It's a 92, 4 cyl, dual plug, vert, auto, with ac

It kept throwing code for the DIS module, so I replaced it with another. The car ran good when I pulled it in the shop. I swapped out the modules and it now won't start. I tried putting the old one back in and it still doesn't start.

It's not getting any spark or fuel injector pulse.

I replaced the following already in an attempt to fix this:

Crank Position Sensor
Coil Packs
Computer EEC-IV

I also tested wires for power and continuity tests. The EEC, Integrated relay control box, Coil packs are getting power. The continuity tests were good, didn't find any breaks. I also did a wiggle test using an engine diagnostics computer to try and find a broken wire somewhere, but there was none.

The realy control box seems to be turning on because I am getting power at the EEC.

I am assuming the EEC is not getting the signal to start up?? From what I can see in the wiring diagrams, the coil packs are controled by the DIS module and the EEC controls the fuel injectors But i'm not getting a signal from either one??

She is a good friend and i've worked on this car since she bought, so I know it's not one of those let him fix something and blame him for another problem deals.

Anyone have an idea of what this could be???

Thanks
Vic

 

[ethangsmith]

My only thought here would be a failed ignition switch. Those cause some real weird electrical issues when they go out. Also, check your ground wires and grounding points.

 

[vp6799]

I found a wiring diagram that shows 2 seperate grounds for pin #7 (ignition ground) that get grounded when you tighten the 2 left bolts on the ICM. That might be a problem since all but the top right bolt snapped while removing the old one. It might not be getting ground signal since only the top right bolt is being used.

Gonna check that out in the morning. If that don't work, I'll look into the ignition switch.

Vic

 

[vp6799]

Found the problem...

The top left bolt is an ignition ground. Since that was one of the ones that broke, I never replaced the bolt. Figure the whole thing grounded on the aluminum backing. Once I drilled and tapped a new hole so the ICM will be held by the top 2 bolts and tightened up all of the pins in the 2 plugs, she fired right up....

Thanks for the help.

Vic