: 94' SLS t073 erratic idle & stalling



rrollo
01-23-04, 01:17 AM
My recently purchased 94' SLS has 96K miles and has been running great until tonight. First was a 'traction control diabled' message on my 26 mile ride home. After a short stop at home, I drove it to the store and immediately it started surging and stalling. Finally after driving it back home with several restarts the T073 was set and the SEL light was on. Any ideas on what to look for? The T073 code seems intermittant. Are there bad ground connection? This is a west coast car but it does have the oil seepage problem with odor. Any help would be appreciated.

carnerd
01-23-04, 10:27 AM
Cleam the intake out... with alot of miles they get clogged and full of gunk from the air. If you open the throttle body and get your finger in there to see if theres alot of gunk... if there isnt dont worry about it its not the problem but if it does I suggest you take it off and spray it with carb cleaner but watch the ISC (idle speen control) motor. Good luck!:welcome:

rrollo
01-23-04, 12:26 PM
I will inspect and clean the throttle plate. The TCS Traction Control System has the code 'T073'. When driving, why would a dirty throttle plate cause the traction control to disable? Just curious? Going out to clen it in a few minutes.

Thanks

DaveSmed
01-23-04, 05:53 PM
You can look up any codes you have here: http://myweb.accessus.net/~090/dtcobd1.html (http://myweb.accessus.net/%7E090/dtcobd1.html)

Logandiagnostic
01-23-04, 09:16 PM
TO73 is a ABS code. Its 'serial data link fault.' These really can be hard to figure out...really hard when they are intermitant.

From your description....I would really inspect the battery cables at the battery. They can look ok but when dismantled can be horrible on the inside with corrosion. Bad battery cables on Cadillacs can cause strange problems like this +false codes etc...

Logan
www.airbagcrash.com

rrollo
01-23-04, 11:15 PM
Ok I cleaned the throttle plate and the idle improved a little on the cold start this morning. After a good warm up the problem is back and more consistant. T073 and S044 is set. The corresponding display says Traction Control Disabled & Ride Control xxx which match the codes. I retightened the ground wires under the block on the passenger side, the ground on the block from the battery, and the battery ground going to the chassis behind the headlamps. These were the easy ones to see. The codes are hard set now so it dosen't stall any more, just runs in the back up mode. When it was intermittent today it would rev up and down irratically, run fine, or set the codes and drive reasonable in back up. It will be cold in the morning to see if they go away again like this morning. I will check the battery tomorrow morning. Thanks! Any other suggestions appreciated!!:bonkers:

Logandiagnostic
01-23-04, 11:26 PM
Did you dismantle and clean/inspect the battery cables at the battery? You will need to remove the cables and remove the small bolts to inspect.

'94......hmmm. There were some bad PCMs made in '94. Your getting a data code.....

This problem has that bad battery cable or hot PCM failure sound to it....


Logan
www.airbagcrash.com
www.logandiagnostic.com

rrollo
01-23-04, 11:52 PM
I will check the battery cables in the morning as you suggest. Where is the PCM on this car?

Logandiagnostic
01-24-04, 12:00 AM
The PCM is mounted inside the car...passenger side firewall. You remove the black lower close out panel....sort of right hand side... Silver box...3 or 4 10mm nuts hold it in. I would try tap testing the PCM.....somethings getting goofy when warmed up. If you tap test the PCM....and the car stalls or does something strange....stalls, sets codes....etc. Its a bad PCM.

Tap testing is a bit of an art. Tap it kind of hard but not too hard. A bad PCM you can often find one spot where you tap it almost everytime.... and the fault or stall occurs. BUT....not always....

Check the cables first.

Logan
www.airbagcrash.com
www.logandiagnostic.com

carnerd
01-24-04, 12:11 AM
Well Im glad it starts easier in the morning! But also check the ISC (idle speed control) its at the bottom right of were the air comes from the filter and hose. There is a 4 prong connector that you can check and make sure theres no dirt or anyhitg thing in or make sure its on all the way. You might want to take the ISC moter out and do a visual inspection to see any ware and tear but... these are not cheap as I am told so be careful. Hope you find the problem soon. Also check vacuum hoses you said the ABS light came on? when your car is idling really bad in nuetral, stomp on the brake and see if anything changes if it does that should narrow down your inspection a little.

rrollo
01-24-04, 12:42 AM
Thanks for the extra ideas. The speedo dosen't work when the hard codes are set either. Thats why I thinking it is electrical grounds or control module. I have never had an IAC that clases these extreme shift in RPM while driving.

rrollo
01-24-04, 03:59 PM
Runs good cold then starts all over this morning. Tapped PCM - no problem. Did find a large amount of corrosion on the + terminal closest to the battery. Cleaned and road tested with no problem. Will road more later today. Thanks for all the help so far!!! I will be amazed if it that simple, but I'll take it!

rrollo
01-25-04, 05:06 PM
Well I got 4 trips since cleaning the battery without getting a T073 code. On today's 5th trip it happened, without any idle problem or stalling, actually runs ok in backup mode. It went directly to a hard code this time. I cleared the code and drove it again without a problem including a heat soak. Are there some TCS reading to look for when the code is present?

rrollo
01-25-04, 07:41 PM
Well I got 4 trips since cleaning the battery without getting a T073 code. On today's 5th trip it happened, without any idle problem or stalling, actually runs ok in backup mode. It went directly to a hard code this time. I cleared the code and drove it again without a problem including a heat soak. Are there some TCS reading to look for when the code is present?

Logandiagnostic
01-27-04, 06:47 AM
Ok....well at least the battery cables are not causing the problem.

In the trunk...theres the forward pull down panel covering the vehicle electronics. In the very center is a large silver box with a 'Bosch' label on it. This is the ABS brain.

Try unplugging and replugging the harness into the ABS brain 5 or 6 times. This should clean off any light oxidation on the ABS box pins that has formed over the last 10 years.

Retest...

Logan
www.airbagcrash.com

rrollo
01-27-04, 09:52 AM
I can't take time to work on the car until this Thursday, so I will inspect the ABS then. I am driving another family car due to my comute until this car is reliable again. Thanks for the next step. I understand some computer diagnostics but am weak on this high tech vehicle.

rrollo
01-30-04, 01:47 AM
Well I reseated the connector on the ABS control module. More driving is required to be sure due to intermittant nature of the T073 code set.
What are all the other modules back there???
The prior owner had removed a heavy duty sound system when he sold the car to me. All the speaker wires and antenna wires have been spliced with new wires leading me to think there could be or was some unusual harness strain on some of the modules while deinstalling the sound system.
Also, I had loosened the cover back there a few days prior to this problem occurring (due to a screw that was too long and protruded though the rear deck) I didn't know that all those modules were back there so I didn't think about it until you told me about the ABS module being located back there. :yup:

rrollo
01-31-04, 12:14 PM
I have reseated the ABS module in the trunk. Still setting codes last night. After a 10 mile drive and a heat soak the hard codes T073 & S044 with P109 in history occured. Also the speedo dosen't work when the codes are present. Tach is fine. Codes would not clear and after driving home in back up mode & it started to stall again at the end of the drive. The car has always seems to crank a bit slowly, even after cleaning the + battery corrosion. There is an atftermarket battery that looks somewaht new that I need to remove to see the cranking amp rating? Could a marginal battery be the cause? But when the codes set last night I could not clear them.

rrollo
01-31-04, 12:52 PM
Just checked codes before removing battery this morning. No hard codes! But in addion to P109, T073, S044 in history were P052, I034, T072.

rrollo
01-31-04, 05:24 PM
T073 is set all the time now. Plus I032, I034, I052, P109, S044, T072, in history with some current when it really acts up. This problem seems to be consistantly worse. Any ideas? :nono: