Matt03785

I am having a reoccuring problem of my T/C light going on among other lights at times and when that light goes on my car shifts really bad and is almost undriveable

Then i'll stop the car ...turn it off...and it works fine....FOR A WHILE (day or 2)

Its been in the shop 3 times this month and they've replaced sensors and modules and the problem remains

i'm starting to think its electrical but i have no idea, When the problem started i replaced the original battary and it was fine for a month or so but it now acts up at least once a week so i'm thinking it could possibly be the alternator

06 Cobalt 2.4 with 85,400 miles on it still has original plugs and original alt

anyone expierenced something similar or know whats up with this thing?

Thanks

alleycat58

85,400 on original plugs????? What do they look like? Have you pulled them and checked?

What sensors and modules have been replaced? I wouldn't think it'd be a wheel sensor, that usually throws an ABS light, but I would suspect an issue with the BCM. It may be a wiring issue as well causing the traction control to go haywire.

alleycat58

Next time it happens, pull the e-brake up one click, it'll ding at you but it should disable the traction control and see if the driveability issue goes away.

Matt03785

i haven't pulled and looked at plugs yet, maybe i'll do that this weekend

they hooked a scanner up to it and it said the TCC solenoid switch was bad so they replaced that

and that didn't do the trick

alleycat58

But they didn't replace anything else? I guess it COULD be a speed sensor, but more often than not that'll throw an ABS light instead of a T/C light. I would bet it's more along the lines of bad wiring somewhere in the TC system. A loose connection or something along those lines, could also cause a faulty reading on the scanner.

Matt03785

the ABS light does come on occasionally in addition to that TC light...the TC light always causes trouble but its usually accompanied with either the ABS light, the SECURITY light or the POWER STEERING light BUT never more then 1 other

so basically its always the TC light along with 1 of the previously mentioned 3 lights

alleycat58

That sounds to me like a BCM going out.

Coblasts

The tc light coming on with bad shifts is usually one of the cam selinoids(intake or exhaust).did they replace those?Dirty oil affects these as well,are you due for a oil change ?

If other lights are coming on randomly then a possible voltage problem it could be.

Check the wires that go to the cam selinoids for chaffing especially if they are near the purge selinoid bracket(known bad spot)

Matt03785

they did replace some of those solenoids...i do a pretty good job with the oil changes, i put mobile 1 in it and change it every 6K

i'm starting to think it might by that BCM the other guy mentioned