ECU Wiring (Resolved)

[usmc0431]

For over a week, I have not been able to start my 95 GSX. One day it was fine, and the next, I got nothing. Symptoms are clicking MPI/MFI relay, stock boost gauge topping out, sometimes the fuel pressure control solenoid valve rapidly clicks, tach jumps in time with MPI/MFI relay when key is turned to on position. The car does turn over. I replaced MPI/MFI relay, and battery. I pulled the ECU and opened it up but saw nothing unusual to my untrained eye. I pulled the rear seat and fuel pump will "bump" on and off when the MPI/MFI clicks. I've undone everything I've done electrically and removed radio thinking something is shorting out. One thing I've noticed on the ECU harness is some splicing. I've tried to attach a picture. Is this normal? The gray tape used to wrap up the splicing doesn't look like a factory job. Plus, there was a wrap of tape around each of the four plugs for the ECU also. The vehicle is stock, I have to pod gauges (boost/air fuel), but the air fuel hasn't been wired yet. There are a ton of "Won't Start/Clicking" threads, and I've spent days looking at them, but some are resolved with ECU replacement but the majority are unresolved.

 

[RoasT BeeF]

That doesnt look like stock wiring to me. Can you post a bigger picture? It is somewhat hard to see where those wires run to that are taped up.

 

[luv2rallye]

Is your ECU case and ground wires grounded properly? It sounds like that's your problem.

 

[FP3065TSI]

I agree with luv2rallye and make sure that the engine has good ground. Get a known good battery, maybe even some starting fluid can make the cranking easier on the engine.

 

[usmc0431]

Here is a bigger pic. I was looking for grounding points for the wiring harness when I spotted this and stopped. It is a new battery. The motor has no problem turning over.

 

[steve]

That is how the factory grounded the shields of the cables for the knock and O2 sensors. The black wires connected to the braid of the three green wires should be grounds.

 

[usmc0431]

Thanks Steve, I can eliminate that as an issue. Once I get those covered back up, I can continue with trouble shooting.

 

[Artago]

Here is a bigger pic. I was looking for grounding points for the wiring harness when I spotted this and stopped. It is a new battery. The motor has no problem turning over.

My wires look exactly like that... So I think it's normal but I can't say for sure.

Here's a pic of mine:
<table style="width:auto;"><tr><td><a href="http://picasaweb.google.com/tomas.beblar/CarsPics/photo#5139962120397193218"><img src="http://lh6.ggpht.com/tomas.beblar/R1TQUNk9AAI/AAAAAAAAE4g/GHJJLCsc5Cc/s144/sensor%20wires%20008.jpg" /></a></td></tr><tr><td style="font-family:arial,sans-serif; font-size:11px; text-align:right">From <a href="http://picasaweb.google.com/tomas.beblar/CarsPics">Cars Pics</a></td></tr></table>

Click the "Car Pics" link to see more pictures.

Tom