bought a SHO, help me make it run

Five years ago...

a friend of mine bought a '93 SHO with a nice body, but 215k miles and a blown headgasket. due to having parted out dozens of them over the years, he also had a known-good engine with only 60k miles, and an equally legit auto- transmission with only 30k. in an attempt to make a reliable daily driver on the cheap, he pulled the car's drivetrain, and installed the low mileage pieces in their place.

when he was done the car would not start. it cranks. if you shoot ether in the throttle body it'll fire momentarily. but it won't run. the fuel pump cycles with the key. there is no pulse at the injector. he tried everything he could think of. swapping computers, ignition modules,etc. eventually he pushed it back into the corner of his shop in disgust.

I just bought the whole car for $900. where should I start?

If it has spark, then the crank trigger is good, and the fuel pump should run with cranking. Is this so?

You have power at the injectors, key on engine off, but no ground pulse on crank?

Answer these and I'll try to track down a wiring diagram.

I confirmed that it starts on ether. I didnt specifically check spark, but would ether ignite without it?

I also confirmed continuity of the wiring harness between the ecu and several of the injectors.

I give this thread 2 hours before Yamaha responds.

belteshazzar wrote: I confirmed that it starts on ether. I didnt specifically check spark, but would ether ignite without it? I also confirmed continuity of the wiring harness between the ecu and several of the injectors.

Ether won't light without a spark. I know this sounds stupid, and is potentially dangerous, but have your or your friend yanked an injector to see if it coughs fuel on crank?

Sounds like fuel flow. I agree with mndsm. Don't catch fire.

I think i need injector pulse before i can expect the injector itself to do anything.

Theres some fuel pressure at the rail. Havent put a gauge on it to see how much. But again, without an injector signal....

Unplug the coolant level sensor in the overflow bottle and see if it fires up. I know it sounds stupid and I don't remember exactly how, but if it shorts out somehow it's wired into the ignition or injectors. It's been a half life since I fixed on those.

You have no pulse, or you have no injector firing? Have you tested with a NOID? If you have no signal, then it sounds like a security issue. I'm not too versed with the Yamaha SHO specifically, but its possible that the ECM is disabling injectors as a security thing. Ford did that for a while, but like I said... I'm no SHO expert.

curtis73 has a good theory, especially since it sounds like parts are coming from all kinds of different SHOs.

really dumb ques? have you checked to see if the inertia switch has been tripped?

curtis73 wrote: You have no pulse, or you have no injector firing? Have you tested with a NOID? If you have no signal, then it sounds like a security issue. I'm not too versed with the Yamaha SHO specifically, but its possible that the ECM is disabling injectors as a security thing. Ford did that for a while, but like I said... I'm no SHO expert.

I plugged my noid in and it did'nt flash.

T i

warpedredneck wrote:

really dumb ques? have you checked to see if the inertia switch has been tripped?

I had the same thought, but i was under the impression it cuts power to the fuel pump. And i still have power at the fuel pump.

so, just going over it, cliff notes? you have fuel pressure? you have spark? you have no injector pulse? (no noid flash)

An undetermined amount of fuel pressure, enough spark to light ether, and my noid didn't flash. Correct.

If the injectors don't pulse it, the fuel is not that important right now. Check the DIS module the 2 bottom mounting screws ground it. If they aren't there the module maybe junk. I would look for missing grounds seeing how the whole drivetrain has been replaced.

A factory 93 SHO alarm will not cut injector pulse. Aftermarket who knows.

Have you asked on SHOforum.com?

And you tested the wiring harness for continuity? DId you also test right at the ECU to see if there is a signal there?

ECU pin numbers are as follows: Cyl 1: pin 58 Cyl 2: pin 59 Cyl 3: pin 39 Cyl 4: pin 35 Cyl 5: pin 15 Cyl 6: pin 12

sell SHO use money to buy running car? Problem solved

bmw88rider wrote: And you tested the wiring harness for continuity? DId you also test right at the ECU to see if there is a signal there?

I checked two of the injector signal wires, cylinder 1 & 3, for continuity. Theyre good. None of the injectors are firing at all. With everything assembled i cranked it over awhile, then pulled the upper intake off, and the lower manifold runners were all completely dry.

The injector red wires should have power. The same power goes to the IAC, egr vacuum regulator solenoid, canister purge solenoid and the intake manifold runner control. If any of those are shorted to ground you won't have power at the injectors. Unplug one at a time to see if power gets to the injectors.

Power comes from pins 37 & 57 on the computer.

fuses are good, correct?

Appleseed wrote: I give this thread 2 hours before Yamaha responds.

My bad, I wasn't on here most of the weekend.......

To the OP, go through this and check your codes the eec has recorded. That should help you find the issue quickly.

http://www.shophoenixproject.com/eec/eec.htm

curtis73 wrote: You have no pulse, or you have no injector firing? Have you tested with a NOID? If you have no signal, then it sounds like a security issue. I'm not too versed with the Yamaha SHO specifically, but its possible that the ECM is disabling injectors as a security thing. Ford did that for a while, but like I said... I'm no SHO expert.

The gen1/2 sho's did not have any "drive away protection" AFAIK(the only sho I have had with it was my '98), my guess is going to be a bad ground in the engine bay or a weak fuel pump(what my '92 died of)

a weak fuel pump will contribute to no injector pulse?

In reply to belteshazzar:

It can, by following that shophoenix link, writing down your codes and then clicking the link for the code listing, it should tell you exactly what is going on. These eec's are quite brilliant to tell you the truth.