Dead SHO, ignition problem??

[SHOGIRL1994]

I was driving to work in my 89 last week and was turning a corner when the car completely shut off on me. No prior symptoms or anything. I steered into a parking lot and tried to start it again. It would crank and crank over but wouldn't catch and start. I had the key in the "on" position for a minute while I sat there trying to think of what it could be and heard the fuel pump prime a couple of times on it's own, making the sound it usually does when you first turn the key to "on" but I wasn't moving the key. I thought maybe there was something wrong with the fuel pump then, but it only did it a few times and I checked pressure at the rail and everything there was good. It will crank over and over all day long but will not start.
I do have gas. Power (battery) is good. I've checked every single obvious ground and wiring pigtail possible.
Any ideas? I had to call in to work today b/c I couldn't get there... any help ASAP would be appreciated greatly!!!

 

[Slo-Sho]

If the CE light stays on while cranking the EEC is NOT recieving the PIP signal.

 

[SHOGIRL1994]

What does that mean?
Do you possibly mean bad CID or CPS ?

 

[Slo-Sho]

It's almost always the CPS...IF the CE light stays on while cranking.

 

[SHOGIRL1994]

THANK YOU. Found another thread with almost the same exact problem, so I'm going to try all the suggestions there as well. I appreciate your time!!!

 

[SonicRiot]

Do you have compression?

It's not usual for a SHO, but timing belts do break...

Just a thought.

 

[SHOGIRL1994]

Timing belt is in great condition. Here is what we tried last night:

Tested spark, everything OK.
Tested voltage to every imaginable wiring connection that had to do with ignition, everything ok.
Replaced CID sensor and CPS and still the same thing.
Checked all wiring to PCM, everything ok.
Swapped IRCM from the 93 onto it, still the same stuff.

When you turn the key on, sometimes the fuel pump will "prime" continuously and the sound "fluctuates" from a higher to lower pitch sound (not getting continuous voltage??)

 

[SonicRiot]

Check the voltage AND amperage at the pump.

Everything may seemingly be ok, but if the amperage is poor due to corrosion, a break, or a short, the pump will run poorly.

Also, check the pressure at the pump and compare with the pressure at the rail.

And I know you have stated that the timing belt is fine, but have you run a compression test? When a car won't start and the obvious is inspected, The first test I go for is a compression test. Easy, quick diagnostic info just to eliminate a mechanical possibility. Expect low compression numbers in all cylinders when the engine is cold. As long as they are above 80 psi in every hole, you have eliminated the possibility of a mechinical problem. If you DID see less than that in every hole, you have a timing problem. In one hole, a valve or ring problem.
I would eliminate the second possibility, as your car wont even start.
A good indication (but not definate) that the timing has not jumped is if the engine does not free-wheel after cranking. If it does freewheel, you have no compression.


So that's why I mention the timing belt as a possibility. It seems as though you may be further along in diagnosis. So yeah, check the fuel pump. And the filter.

 

[Bizzy]

What about your battery terminals? Are they clean and tight at all connections? It doesn't matter how much juice the battery has in it if it can't transfer the proper amount of power to the car and it's operating systems for it to run.

If the terminals are aftermarket ones you might consider replacing them with new ones. Clean the wire prior prior to installing the new one and make sure that the terminal on the battery doesn't have any crud build up on it.

If the ground/positive cables are stock then I'd suggest double checking the wire where the wire casing and the terminal meet. I ended up replacing my terminals because the wire was starting to break where the lug attaches and it wasn't allowing full juice to the car. Once that starts to happen the usual battery crud builds up in there which will further inhibit proper power transference. If you find that this junction is damaged and the wires are starting to break, you can try to clean it to see if that helps at all, but if I was you I'd just hack that sucker off and replace it with an aftermarket one. This way you could peel back the wire casing a bit and make sure that there is no crud inside.

Double check that the ground wire on the battery side that goes to the PCM is also attached and that it's connection is a solid one. When that wire is unplugged the car will crank all day and not start.

Just FYI, you should make sure that the IRCM that you put on there is the same letter code. If it's not you will harm other systems in your car by using it.

Also, do you have vRef?

 

[SHOGIRL1994]

Well, I took the computer out of my 93 this morning and put it in hte 89. Yes I know that they are diff, but i wanted to see what happened. THe one out of the 93 is an y2j, the one out of the 89 is a b9c. Well when I hooked it up the 93 computer let the car start....yay... but then when I tryed to give it gas it fellflat on its face and chocked itself. SO , I 'm thinking it might be the computer that is bad on hte 89 cause I've checked everything else i can think of. The battery terminals and all the grounds leading off of it are good and tight. So what do you folks think... since the car did start and run with a diff computer, but doesn't run with it's own coputer. Thanks again.


Nick
(too lazy to log in under my name)

 

[SonicRiot]

Sounds like you have narrowed it down to a bad computer. Put the computer back in and check the voltage at the fuel pump while it primes and while cranking. Trace the circuit back all the way to the relay and the computer. If everything checks ok downstream, the computer may not be supplying the ground for the pump on demand.

Oh yeah, check the resistance at the pump relay, both the computer control side and the pump power side.

 

[SHOGIRL1994]

All voltages/amperages check out ok. I went to the junkyard in search of another computer on Wednesday and pulled one from another 89. The 3-character code was not the same, but the rest of the numbering on the label was. He gave it to me to try out for free (guess it pays to know people in the junkyard business!), so I thought what the heck. I get it home and try it out, and it doesn't want to start with this one. Now I'm not sure what it is because at least it STARTED with Nick's computer, but I put another different one in and it doesn't start. (????) He cross-referenced the B9C code on my computer and said the closest one at a scrap yard he could find was somewhere in south Florida. He had a good point too: I might be hard pressed to find a used computer for this car (if in fact that is the problem) because it's a California car.
I have just about given up. If anyone has a B9C computer they can part with by any chance, PLEASE pm me... otherwise I'm towing the car to a shop and will have to have it diagnosed there.

 

[Gregory]

It's almost always the CPS...IF the CE light stays on while cranking.

having a problem with my 94 it dies out of nowhere it wont start right away but will after about 15min somewhat of the same problem as she did sorta

 

[Sho-N-Go]

I have just about given up. If anyone has a B9C computer they can part with by any chance, PLEASE pm me... otherwise I'm towing the car to a shop and will have to have it diagnosed there.

When it fails to just HANG parts on it is probably best to have someone with experience look at it. I cant actually believe you know people in the Junkyard business. your car either doesnt have spark,fuel,or timing. it also may have no V ref. But I think it is best to give up and take it somewhere

 

[SHOGIRL1994]

haha, well my dad used to work at a wastewater treatment plant in the industrial section of town that happened to be next door to a junkyard. He became really good friends with the guys over there, so any time I need anything I just go over there... they put it on my "tab".
Anyway, I had the car towed to a shop yesterday and they are supposed to let me know what's wrong with it by tommorrow afternoon. Hopefully it's just the computer.

 

[Slo-Sho]

The DIS module and/or it's related wiring were checked OK?
Was the EEC able to perform the KOEO diagnostic?
When you swapped the IRCM's did they have the same letter?
*What does the CE light do while cranking the motor?*

 

[SHOGIRL1994]

The DIS module and/or it's related wiring were checked OK?
Was the EEC able to perform the KOEO diagnostic?
When you swapped the IRCM's did they have the same letter?
*What does the CE light do while cranking the motor?*

DIS is fine. EEC won't give me anything but "all clear", I'm assuming this is because the car hasn't actually ran since the problem occurred and is unable to store the codes. IRCM's were the same, I'm pretty sure. (Not at home right now, can't check.) The CE light is lit when cranking, sometimes I get a tach, sometimes I don't.
The car has now been at the shop for 4 days. They still haven't been able to find the problem . However, when I called them for an update yesterday afternoon, they were no longer getting spark either (when we first started testing things ourselves, and when they first got the car at the shop, we were getting spark).

 

[Slo-Sho]

The CE light is lit when cranking

This important info tells you that the EEC is not recieving the PIP signal as state earlier in the thread. You have to find out why.

 

[SuperchargedSHOguy]

Tara, after reviewing this a few times I would guess your computer is toast and the other one you tried was not compatable or is just as bad as your origional. Did you post in the WTB? If you wanted to upgrade, we are pulling an entire harness out of a 92 along with dash and computer...It would be alot of work to swap out but you could do it.
If you have been swapping out sensors like the cps and cid and nothing then if sounds like something major...especially with the way your pump was acting and now no spark. You need to eliminate the computer as the problem by getting it refurbished (yes places will refurbish them) or getting a working used one.

 

[SHOGIRL1994]

The shop I took the car to actually refurbishes computers but he said he couldn't find anything physically wrong inside it, ie. no bad resistors or other components. Basically I've found one from another forum member, just waiting to find out how long till he can ship it to me. The shop finally went back to the idea of it being the computer because they spent the better part of a week testing everything else they could think of to no avail. They are basically waiting on me to come up with another computer to see if that works.