1991 Olds 98 problems
Fortune50
06-16-2005, 09:11 PM
Hi, a buddy's '91 Olds 98 3.8L is having a couple of problems:
The tranny seems to not shift into 2nd gear out of first gear, I don't know what tranny he has, he said it was replaced under the original factory warranty and the pan says 60 on it. Once its up to speed, it will upshift to 3rd gear out of 1st (revving a bit high obviously) and upshift into OD ok, though. He said he changed the tranny fluid/filter about 9 months previous to this happening. Any ideas what may be up? Also how does he determine what tranny he has and if it's electronic or not?
Also, his car starts and runs fine but if shut off warm, most of the time it will not restart until cooled off. It turns over, but won't start. Crank sensor? Ignition related? I told him when it happens again to quickly spray some throttle body cleaner into the intake and see if it'll then start up, if not then I told him to try and check for spark at one of the spark plugs for a way to see if it can be narrowed down to a fuel or spark related problem.
Any advice is welcomed.
The tranny seems to not shift into 2nd gear out of first gear, I don't know what tranny he has, he said it was replaced under the original factory warranty and the pan says 60 on it. Once its up to speed, it will upshift to 3rd gear out of 1st (revving a bit high obviously) and upshift into OD ok, though. He said he changed the tranny fluid/filter about 9 months previous to this happening. Any ideas what may be up? Also how does he determine what tranny he has and if it's electronic or not?
Also, his car starts and runs fine but if shut off warm, most of the time it will not restart until cooled off. It turns over, but won't start. Crank sensor? Ignition related? I told him when it happens again to quickly spray some throttle body cleaner into the intake and see if it'll then start up, if not then I told him to try and check for spark at one of the spark plugs for a way to see if it can be narrowed down to a fuel or spark related problem.
Any advice is welcomed.
91olds98
06-17-2005, 01:17 PM
About your trans:
To determine what type it is, you need to look on the bottom of the transmission oil pan. It is most likely the 4T60-E Hydra-Matic Transmission, and it is electronically controled. It sounds like the shift solenoid is bad - on this year they have been known to have a bad ground connection of the shift solenoid. I would check this first. If its not that, the solenoid may be bad - check it with an ohm-meter (if you need detailed instructions, consult a shop manual). Otherwise, it is probably a problem the the valve body - in this case, its time for a new trans.
How many miles are on this trans?
Hope this helps
Good luck
To determine what type it is, you need to look on the bottom of the transmission oil pan. It is most likely the 4T60-E Hydra-Matic Transmission, and it is electronically controled. It sounds like the shift solenoid is bad - on this year they have been known to have a bad ground connection of the shift solenoid. I would check this first. If its not that, the solenoid may be bad - check it with an ohm-meter (if you need detailed instructions, consult a shop manual). Otherwise, it is probably a problem the the valve body - in this case, its time for a new trans.
How many miles are on this trans?
Hope this helps
Good luck
91olds98
06-17-2005, 01:27 PM
Sorry, I forgot to address the other issue:
If this model is the Regency Elite, you have a pass key starter. It is possible that the pass-key is not registering correctly, (or you have an aftermarket key) or it could be a crankshaft position sensor. In either case, have a shop (or AutoZone) check the trouble and error codes. If it is a sensor problem, it will spit out an error code. If not, I would chcek a few other things first, such as the pass key. However, it sounds like the ECU is not allowing the injectors to fire. If thats the case, then checking the error codes will tell you why the ECU did not allow the injector timing sequence to start. (Fuse maybe?)
As far as the temperature dependance, Im not sure, and would need more detailed information.
Hope this helps
Let me know.
Thanks.
If this model is the Regency Elite, you have a pass key starter. It is possible that the pass-key is not registering correctly, (or you have an aftermarket key) or it could be a crankshaft position sensor. In either case, have a shop (or AutoZone) check the trouble and error codes. If it is a sensor problem, it will spit out an error code. If not, I would chcek a few other things first, such as the pass key. However, it sounds like the ECU is not allowing the injectors to fire. If thats the case, then checking the error codes will tell you why the ECU did not allow the injector timing sequence to start. (Fuse maybe?)
As far as the temperature dependance, Im not sure, and would need more detailed information.
Hope this helps
Let me know.
Thanks.
Fortune50
06-17-2005, 07:30 PM
Thanks a bunch for your reply! Well he took the car into the local GM dealer (Chevy/Caddy/Buick) and let them diagnose the no start problem. They told him it seems to be a crank sensor or cam sensor related problem. The only trouble code they've gotten is 12. ??? Anyhoo he said his tranny does NOT have a cable that connects it to the throttle body. Also his car has cloth seats, does that mean it's not a Regency Elite? I'd like to check out his tranny's 2nd gear solenoid, is it located on the outside of the tranny case? If so where? Is the ground wire located near it? Thanks again.
91olds98
06-18-2005, 09:25 AM
Ok, this one is a little complicated. Since your trans is the 4t60-E, there will be a circular plug comming out of the front, underneath the throttle body, near the air intake plenum. How it works, is the ECU will electronically ground the solenoid terminal, and another system will supply the +12v. The +12v system will supply the correct voltage when the conditions are correct, and the computer will ground the output signal when its conditions are correct. As far as I know (and im doing this all from memory) three of the four shift solenoids, the 1-2, 3-4 and PWM all share the same ground connection, but unfortunatley I don't remember which wire it is comming out of that terminal. Your local dealer should be able to tell you, since they all have the repair manuals.
However, I don't think its an electronics issue here. (The starting problem maybe, but not the shifting one.) For this model of car, the vavle bodies on the auto-trans tend to wear out around 180k, and the solenoids wear out relatively quick too. My first instinct is to check the 1-2 shift solenoid. If you "hot wire" the solenoid, you should be able to hear it clicking over underneath the trans side cover. (Be sure to get the wiring correct, since 'hot wiring' the solenoid can damage other electrical components!). If you hear it click over when the engine is off, then its probably the vavle-body. If you don't hear it click over, then its either the wiring, or its the solenoid itself. Either way, a quick test by a repair shop should be able to easily diagnose this - they have a fancy test tool that connects to the ECU.
(P.S. - Just to cover my butt, I'm not a professional - merely someone who has had some experience, and a little knowlege about the issue. So don't do anything I wouldn't do :) )
Hope this helps, let me know how it turns out
However, I don't think its an electronics issue here. (The starting problem maybe, but not the shifting one.) For this model of car, the vavle bodies on the auto-trans tend to wear out around 180k, and the solenoids wear out relatively quick too. My first instinct is to check the 1-2 shift solenoid. If you "hot wire" the solenoid, you should be able to hear it clicking over underneath the trans side cover. (Be sure to get the wiring correct, since 'hot wiring' the solenoid can damage other electrical components!). If you hear it click over when the engine is off, then its probably the vavle-body. If you don't hear it click over, then its either the wiring, or its the solenoid itself. Either way, a quick test by a repair shop should be able to easily diagnose this - they have a fancy test tool that connects to the ECU.
(P.S. - Just to cover my butt, I'm not a professional - merely someone who has had some experience, and a little knowlege about the issue. So don't do anything I wouldn't do :) )
Hope this helps, let me know how it turns out
Fortune50
06-20-2005, 08:54 PM
Hey, thanks again for the info.
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