Sc won't start, no upshift light, fan comes on

JT15601

Registered User
Ok so I went out to start my sc this morning and in KOEO the fan came on and I figured that was weird. Then I cranked and cranked and cranked it and it wouldn't start. But it started on starting fluid and will run like that but it runs like there is no MAF sensor. Like it will idle but if u rev it it dies and if u unplug the MAF nothing changes. Also the upshift light isn't on when I turn the key to run (I know it should be) and the fan comes on when I turn the key to run as well. Could this be a bad IRCM? I can't seem to find any for sale either. The car has good spark, good fuel pressure and a new can sensor and a known working dis module.
 
What year is it? Why was the cam sensor replaced?

Check the crank pulley/balancer to see if it's loose, wobbly or broken.

Check the ground wire on the header panel near the battery.
 
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Its a 1989. The can sensor was replace because when the car would get warm after driving like 20 miles it would start to run on like half the cylinders and have to be shut off and turned back on. That fixed the problem that was almost a year ago. The ground is good as well as the HB
 
Did you run the codes yet?

Use a test light to see if the injectors are firing when you start it.
 
Did you run the codes yet?

Use a test light to see if the injectors are firing when you start it.

I didn't run codes on it yet but the cel has been on for a while now. And the injectors don't pulse when you crank it but they work if you start it on starting fluid
 
While you wait to run the codes, check the large ignition switch down on the right side of the steering column to see if it is opening up (not the key switch).
 
While you wait to run the codes, check the large ignition switch down on the right side of the steering column to see if it is opening up (not the key switch).

What ignition switch? I don't know where exactly you're talking about
 
Remove the two-piece plastic surround/bezel between the dash and the steering wheel. There are three long phillips head screws accessed with a long driver from below. It can help to alternatively tilt the wheel to get them out once the screws are removed and the upper and lower sections are snapped apart.

The look down on the right side of the steering column for a long switch & connector with several wires that looks like this:

http://www.autozone.com/autozone/pa...rd/_/N-igp61Z9rigt?itemIdentifier=368100_0_0_

It's not unusual for the older switches to open up/come apart and make strange things happen.
 
Double and triple check the ground for the computer, as above the one to core support in front of the battery. When you turn on the key and the fan comes on and no injector pulse, exactly what you r describing, it means the computer is dead. Not saying the computer itself is bad, just that it may not be powered/grounded properly (broken wires, bad ignition switch, also as mentioned above). Restorected a 90 XR7 that had been sitting a few years, and had a bunch of the electronics removed. After 2 days of swapping "known good" parts in and out of it, it was that ground wire, and I'm pretty sure that was what took the car off the road in the first place. The prev owner just never found it and gave up.

Adam
 
Ok so I checked that ground wire as well as the ignition switch they are both good. I even removed the ground and sanded it and reattached it and checked with a test light to make sure I was getting good ground. What next?
 
Hmm. There's a recent thread, as well, with a guy with a 35th anniversary SC that is having the same problems as you.....fuel pump primes, but no start. He hasn't solved his problem, either.

Have you tried disconnecting the battery and resetting the ECU?
 
Hmm. There's a recent thread, as well, with a guy with a 35th anniversary SC that is having the same problems as you.....fuel pump primes, but no start. He hasn't solved his problem, either.

Have you tried disconnecting the battery and resetting the ECU?

I had it disconnected for like an hour and that didn't help but I disconnected it again yesterday and left it over night and its still disconnected. And my fuel pump doesn't prime it runs constantly in KOEO as well as the fan but the both turn off when I shut the car off.
 
Its strange that the fuel pump comes on and stays on. If its an ECU problem the pump ususually will NOT cycle. The ECU should cycle it for 5-10 seconds each time the key is turned on. If you have access to a good ECU I think I would try swapping it in. They r not known for going bad, but the fan/pump coming on and staying on with the key seem to be signs of a n ECU problem.

Adam
 
Its strange that the fuel pump comes on and stays on. If its an ECU problem the pump ususually will NOT cycle. The ECU should cycle it for 5-10 seconds each time the key is turned on. If you have access to a good ECU I think I would try swapping it in. They r not known for going bad, but the fan/pump coming on and staying on with the key seem to be signs of a n ECU problem.

Adam

I do not have access to another ecu. No one around me that I know of has an sc. And I did leave the battery unplugged for 24 hours and nothing changed when I reconnected it. Could it be an IRCM problem because if you unplug that the fuel pump and fan turn off
 
Its strange that the fuel pump comes on and stays on. If its an ECU problem the pump ususually will NOT cycle. The ECU should cycle it for 5-10 seconds each time the key is turned on. If you have access to a good ECU I think I would try swapping it in. They r not known for going bad, but the fan/pump coming on and staying on with the key seem to be signs of a n ECU problem.

Adam

I'm not an ECU expert, but I was thinking the same thing.....if the fuel pump cycles, then one would think that the ECU is still good. Unless part of the ECU can be fried and part of it can be still good, but one would think that the ECU is one of those things that if it gets fried somehow (ie: shorting wires to 12V power), that it would just outright be done for and wouldn't operate anything. Trying to use logic, it still seems like a grounding issue, like the ignition isn't being grounded.

Was there anything that you'd modified or repaired recently that may have knocked loose another wire somewhere? Seeing as that the car fires up on starting fluid, if we're to go on logic, the problem seems to lie in the ignition, but not in the switched ignition, either. You didn't mention whether the car has accessory power or not.....i'm assuming that you do? Coil pack wouldn't be bad, seeing as that the car stays running once it is started.

Does the DIS tell the coil pack what to do? Could it still be the DIS?
 
Everything else in the car works. Power seats, seat belts,radio, lights inside and out etc. And to be honest I drove the car home from my neighbors house the night before at about 2am after a few beverages but it fired right up and ran fin the whole way home. I have not modified anything within the last 6 months. The previous owner had bigger injectors and fuel pump installed and had the car dyno tuned. But it ran fine when I got it and had ran fine since.
 
Ok so I checked that ground wire as well as the ignition switch they are both good. I even removed the ground and sanded it and reattached it and checked with a test light to make sure I was getting good ground. What next?

You mean you sanded the ring terminal?

Did you check that the black inline connector on that wire, down in front of the battery, is connected tightly?
 
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