yep, another dead sho thread, non starting

[iskatevert]

IT's ALIVE!!

Ok guys, help me out if you can. I have a 1990 MTX 3.0 SHO that will not crank at all. I checked many old threads, many different searches, and still havent come up with anything that makes sense. Here are the symptoms and a few things i have checked out.
When i bought the car the guy selling it had drilled out the old ignition cylinder in the column and mangled it all up, along with the steering wheel bolt. Apparently the keys had been lost and this was better than getting a locksmith... I got a new steering column and put that in from the same year sho, all wires plugged right in and were exactly the same color. He had started the car when i saw it with starting fluid and by jumping the starting solenoid. I tried recreating this situation at home, but cannot get it to even crank. Could this method of starting have fried something?
With the new column installed i also replaced the igntion cylinder with a brand new one. Works as it should, but the car will not crank the car at all.
Fuel pump will not prime either. The only cel that i pull up when checking codes(KOEOff obviously) is 95 - fuel pump secondary circuit failure. This led me to the IRCM, not sure if it is bad or not though. Not sure how to check voltages on the IRCM, but at the fuel cutoff switch in the trunk both leads register 0 volts when the key is turned to on.
When I try to crank it(clutch pedal depressed) the CEL stays steady on and the car acts as though the clutch is not depressed. This led me to think it might be the clutch interlock switch, but theres no power going to that switch even when you try to start it. Used a multimeter to check as many things as I could, but I'm not getting voltage anywhere in the ignition relay. I read about checking the engine fuses, but in the 90 there seems to be no fuse panel in the engine bay, would this have the fuesable links that i read about? I don't know where they are or how to check them.
Also, could all these symptoms be caused by a bad CPS? I would think that this would allow me to at least crank the car some... am I correct in thinking that? The fuel pump issue is there, but right now I'm more interested in figuring out why the ignition wouldnt be getting any juice. What "fuseable links" should i check and where are they? This car can be a frustrating one I can see!

 

[iskatevert]

edit, found out what a fuse link is, all coming off starter solenoid seem to be connected and checked to see if they were stretchy, (indicating failure), all were fine.
i think the ircm could be the culprit still, would be nice to have another (wink wink) to install to check. would the ircm if bad allow the car to crank, or would it lead to the symptoms described above?

 

[bmcreider]

If the fuel pump isn't priming, are the small wires that connect to the battery connected well? One time I removed the battery and reinstalled it, the car worked fine but then died all of a sudden on the road....I thought my fuel pump was dead but it ended up that the connection of those little wires had gone awry...made them tighter and it started right up.

 

[projectSHO89]

Since you have no power at the WHT-PNK wire at the clutch interupt switch, suspicion has to go back (circuit-wise) to the ignition switch and its supplies.

Per the 90 schematics, there shouild be five YEL wires going to the ignition switch. All should be ALWAYS HOT. If not, check the black fuse link E at the starter relay. It should feed out via a YEL wire.

Neither the CPS or the IRCM will prevent starter cranking. Don't think it's your problem. I'm suspicious of that column transplant. If the mechanical linkage for the ignition switch isn't installed just right, it can't crank. I found that out the hard way when I replaced the switch in my car.

Steve

 

[iskatevert]

Since you have no power at the WHT-PNK wire at the clutch interupt switch, suspicion has to go back (circuit-wise) to the ignition switch and its supplies.

Per the 90 schematics, there shouild be five YEL wires going to the ignition switch. All should be ALWAYS HOT. If not, check the black fuse link E at the starter relay. It should feed out via a YEL wire.

If the mechanical linkage for the ignition switch isn't installed just right, it can't crank. I found that out the hard way when I replaced the switch in my car.

Steve

Ok, finally got back around to playing with the car, and this is what I have found.

All five YEL wires are indeed hot at the ignition switch. I played with the mechanical linkage a whole lot and the starter solenoid is still not getting power, nor is the clutch interrupt switch. Car still will not crank with the key turned to start at all.

I replaced the IRCM and the fuel pump relay was bad in my old ircm, as the fuel pump will now prime. The only question I have about that is the part number, i replaced mine (1990 part # e9df-12b577-AB M code) with one out of a 1991 (part # e9df-12b577-AA M code). What is the difference between these units, and is it bad to swap them permanently?


Arrrghhh, this car is frustrating! How can I check for shorts, or maybe start the car other ways?

 

[iskatevert]

OK, friend came over and played with the mechanical linkage in the steering column... now we are getting voltage at the clutch switch and the starter solenoid, no crank tho so I am going to the parts store to get one right now. Still need to know if that new IRCM is ok to use or if i should go get one that matches identically (if possible)?

 

[iskatevert]

Still not cranking... possibly the starter went bad i think now? The new solenoid audibly clicks when the key is started, so thats a plus over the old solenoid. What brand starter should I try to get, seems like it can be a failure prone rebuild part?

 

[somedude_001]

i'm not sure when they changed the starters over to the updated style like mine on my 94ATX but there is a little yellow wire that connects to the starter and if that is not plugged into the starter you will hear the relay click but the starter will now activate. for reference my starter has the sylonoid attached to the starter, I think yours may be different. infact i'm pretty sure it is, the little wire i'm talking about is nothing more than a signal wire.

He had started the car when i saw it with starting fluid and by jumping the starting solenoid.

that didn't raise suspisoin about the car? at any rate yse it can cause damage but it is unlikely, there is no reason to ever use starter fluid on a fuel injected car, if the 3 main components function then it will run period.

 

[projectSHO89]

The IRCM swap is probably okay. I wouldn't worry about it, just different production rev levels.

Verify proper connections at the starter relay. Of the two main lugs, one should go directly to the battery positive terminal. It should also have all of the ring terminals for the other wire harness connections on that lug. The other large lug should go directly to the starter motor. The small side terminal should accept the push-on connector that runs back to the ignition sswitch via the clutch interlock.

Using your meter, check for voltage on the starter feed terminal while the ignition switch is in START. If none, then either the relay is defective or you lost the relay drive power. If batt voltage is present, check for it at the starter terminal. If it is there, then the starter is likely gone to starter heaven. Verify the integrity of the negative cable from the bnattery to the starter mounting bolt before deciding to purchase a replacement starter. If you get a new starter, pay extra for the one with the lifetime warranty. Given the quality of rebuilds, you will likely need it.

Steve

 

[93_blk_blk_mtx]

How old is your starter? Chances are the starter is faulty, and make sure you pick up the original part number for your 90 IRCM. These IRCM are very sensitive to other IRCM, espcially if they are not the exact part and letter code.

 

[iskatevert]

I am wondering if a faulty ground somewhere, like the engine block to chassis grounding strap, could also cause a non-cranking condition? where would most of the important grounds/leads on the car be? If this rain lets up tomorrow I will be out there with the multimeter again... see if the starter is indeed getting voltage after the solenoid terminals.

 

[iskatevert]

Thanks to everyone that helped out! Today I finally got the car running again, first time since I bought it (feb 17). Thank you so much search function!!! I will def be donating some money to the forum for being such a good resource!


BTW it was a dead starter that was not letting it turn over, but there were also probs in my steering column swap.