Interesting problem with the GF's car

[OffshoreDrilling]

2005 Mustang, V6, Automatic.


Under hard braking, the car will come out of gear, or feel like it does, then pop back into gear about three seconds later, and the engine will stall on occasion at this time as well. She claims the car started doing this a couple years ago after getting her rear brakes done. No codes, no lights, nada. The car is out of warranty FYI. She knows that the car does this and has adjusted her driving habits to it, which absolutely drives me nuts. She will brake very softly from a higher speed and stop entirely too close to whatever car is in front of her because she is worried about it stalling. I havent spent any time looking at the car yet, its been too cold out to get myself motivated.

Sounds almost like two problems to me with the given symptoms. I can see the engine stalling under hard braking from having a vacuum leak, but the trans shouldn't be coming in and out of gear.

IAC?
messed up calibration in the TCU?

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[KagA152]

the engine stalling could be the converter not unlocking, popping in and out of gear seems odd though. i dont know how smart the tcu is, but maybe the it sees the converter is still locked up and puts it into neutral? do you have access to a real scan tool to check and see if it has any trans code?

 

[OffshoreDrilling]

I was just on the phone with her, she said when it comes out of gear "the engine gets really quiet", and also she told me that it needs to be put in park, then drive again to get it to move on occasion.

I was thinking about the same thing with the converter not unlocking, bogging down the motor and causing it to stall.

No I do not have access to a real scan tool.

 

[bikrboy128]

2005 Mustang, V6, Automatic.

well there's the problem

i've seen transmission solenoid packs on the ford 5spd autos cause some funky transmission problems (hard shifts, long reverse delay, etc). i'd be willing to bet her car has an intermittent sticky solenoid. you're more than welcome to swing by the shop and hook my snap on scanner to it to see if anything is stored in the TCM.

 

[HILROD]

The brake switch goes bad a lot on those cars. It controls the unlocking of the converter under braking. It's easy to replace and is cheap.

 

[TonzKnock-G]

^sounds like a winner

 

[OffshoreDrilling]

well there's the problem

i've seen transmission solenoid packs on the ford 5spd autos cause some funky transmission problems (hard shifts, long reverse delay, etc). i'd be willing to bet her car has an intermittent sticky solenoid. you're more than welcome to swing by the shop and hook my snap on scanner to it to see if anything is stored in the TCM.

I told her that I was expecting someone to quote the "2005 mustang, v6, automatic" and say that was the problem haha!

I'll keep you in mind if I dont find anything wrong with it right away. I do have something on my truck you might be able to help me with though. Ive had a stabilitrack light on for 4 months, can you read into that? I think its just the sensor in the steering wheel, but dont really feel like throwing parts at it until I find a definite answer. Bad wheel speed sensors cause issues with the stabilitrack too, but I think Id be throwing an ABS light also if one were bad.

The brake switch goes bad a lot on those cars. It controls the unlocking of the converter under braking. It's easy to replace and is cheap.

Thanks HILROD. Im going to take a look at everything else first before I go out and buy any parts. Unless I find any glaring problems, that is going to be the first thing I try.

 

[bikrboy128]

I told her that I was expecting someone to quote the "2005 mustang, v6, automatic" and say that was the problem haha!

I'll keep you in mind if I dont find anything wrong with it right away. I do have something on my truck you might be able to help me with though. Ive had a stabilitrack light on for 4 months, can you read into that? I think its just the sensor in the steering wheel, but dont really feel like throwing parts at it until I find a definite answer. Bad wheel speed sensors cause issues with the stabilitrack too, but I think Id be throwing an ABS light also if one were bad.

yeah my scan tool should be able to read that. just lemme know

 

[OffshoreDrilling]

Whats your work schedule like? I dont live down the street any more.

 

[bikrboy128]

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