The car would just start shifting in and out of gear while cruising on the freeway. In several instances it would also shut down and i have to literally cruise without power and try to restart the car while doing so. A couple of times i stopped completely inorder to get the shifter out of gear and start the car. The shifting is abrupt to the point that it feels like the car is surging forward, braking, surging, braking all within milliseconds of each other.

This has already happened several times and since there is no code being thrown nor is the SES light on, the dealer can't figure out what's happening. And it happens erratically but often enough to make me worry about it.

Anybody have any ideas what could have gone wrong? Several have suggested it might be the VTC (?) recall but i had hat done quite some time ago. The dealer also ruled out transmission slippage since the car shifts fine 1-2-3-4 from a stop. He did bring up the MAF for having a K&N filter.

Your help is always appreciated.

Thanks.
- Mike

 

anyone?

....

 

somebody's gotta have an idea

 

battery dying?

 

I'm assuming it's a 4AT...correct me otherwise

When you say "shifting" you mean that with the car in D it seems to be "jerking"?
Or do you mean that the car is suddenly downshifting into a lower gear, or freewheeling (like it was in neutral), etc.

What happens to the tach when this problem happens? Does it jump around?
Do all your warning lights come on or does everything shut off like the battery was disconnected?

My immediate suspicion would be a bad MAF. The surging you describe is often caused by an AFR/mixture issue, as would be expected if the MAF was sending bad data to the ECU, causing the ECU to not send enough fuel or too much fuel to the engine. Start the car and let it warm up, then disconnect the MAF (this WILL cause a check engine light) and attempt to drive it -- does it feel the same when it happens on the freeway (surging/no power?)

Other possibilities might be a cam/crank sensor that's going bad and intermittently dropping signal, and/or coil packs (especially if you have a 2k or 2k1) going bad.

 

Thanks so much for the response and sorry for the late response guys, just came back from the hospital (separate issue).

Anyway, can't be the battery - i just replaced that recently and so far the charge is good.

paralyse, yep it's an AT. I'd say it's closer to your second description - that is the car is in D then it suddenly downshifts, tach goes wild, car jerks around and gear changes down/up in successive manner. The warning lights didn't go off the first time it happened - in fact i lost complete power. The successive times it was either i just immediately lost power or the lights went on for a short while.

 

im not sayin im right, but i just had a similar problem on my 90 miata, and it turned out to be the slave cylinder.

good luck!

 

do you have any electrical work done on the car? New headunit in the sterio... subs, amps... my brother is a mechanic and he told me not to change electrical components in my max. he said he has had a ton of them come in with blown "BCM's" i think he called them because people have changed something electrical like headunits and lighting...

 

I would agree with paralyse, I think that you really need to concentrate on the MAF or crank/cam sensors, that is the most common problem with the symptom you seem to be having. A shift in your transmission at that speed would be somewhat catastrophic.