Resolved 2G No Start; ECT Issue?

[Deeno]

Kinda confused about this one. I’ve got a 97’ GSX that’s cranking, but doesn’t start.

I took it into a pretty well reviewed Trans shop for a total rebuild, and the car fired up no problem before they started taking things apart. They got the trans dropped, rebuilt and finished, but low and behold; the car just cranks. Fired up once straight into Limp Mode. Haven’t gotten it to run since. I ended up having to have it towed home so I could take a look at it.

I’ve been through the No-Start Checklist multiple times. Timing is perfect. The Compression checks out. Air and Spark aren’t an issue. Intake is fine and new 8mm wires and gapped .28 plugs installed.

The only thing I can think of is fuel. It’s getting to the rail at 43.5psi which is recommended, but it’s just dripping through the injectors. The fuel pump works, the line is solid, and the pressure regulator should be ok. I’ll be replacing the fuel filter just to be safe.

What I did notice was the wiring had been pulled out of the pigtail that connects to the ECT harness. Maybe the ECU is reading the engine as overheated due to the lack of an ECT and not supplying fuel?

Any help from anyone would be greatly appreciated. I’ll post up a picture of the ECT so you guys can see what I’m seeing.

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[luv2rallye]

Well that definitely needs fixing first.

 

[miguelmcv]

On a 2g, if the ECU doesn’t detect sensor temp, it will send to much fuel flooding the sparks and avoiding to run, even if the sensor is bad, it will flood it.

Fix the sensor pigtail, clean/dry the sparks plugs and try again, if all is good it should start.

 

[motomattx]

A coolant temp sensor issue will prevent start on these cars, as mentioned fix that sensor and fix it right before going any further.

 

[Deeno]

Went out and got a new sensor installed. New pigtail soldered in as well. (For reference it’s an SMP S820) Looks 99% the same, only had to sand down the left side rail on the sensor and it hooked up perfectly. Should work for now.

Cleaned and dried the plugs, charged up the battery, reconnected the vacuum lines and let the ECU reset. Ran it through all gears and gave it a shot. Started up on the second attempt.

Idled high at first, but evened out at 1k flat. Sounds real good too.

I’ll be able to take it out Saturday and road test it after I install on a few new parts.
Massive thanks to you guys.

 

[miguelmcv]

Glad she is running.

If you haven’t done it, make sure you do a boost leak test, if there is a very minimal leak (tiny leak) make sure to fixe it, you will get surprise how good it idles.

When I find tiny leaks like the throttle body Orings, I put everything back and keep driving it till I get the parts, most of the time, those Orings has to be ordered, so it takes some time.

 

[Deeno]

I’ll for sure check into it. I’ve got some new parts hopefully arriving tomorrow, so I’ll knock out a leak test after doing the installs on those.

Sounds like a good weekend project to me.
Thanks for the heads up.