6f50 rpm stumbles when braking

[lolford]

I have about 70K miles on the car and did a flush 20K miles before at the Ford dealer.

The car idles at ~600 in gear. When braking I'll see the engine coast then when I fully stop it dies down to 350rpm then adjusts back to 600. The engine fully cut out once when braking on a upward hill but that was a year ago. Another weird issue I have is when I put it into drive from park it will start coasting, then sometimes there is a "thud" and it starts moving with more power.

I'm clueless about transmissions but is this the torque converter taking time to lockup? Those are the only 2 times I see issues.

 

[wpod]

Dealer question?

 

[Warstud]

It sounds like your assuming it's transmission related but it sounds like the throttle body needs cleaning.

 

[supton]

I don’t think convertor. Can you check trans oil level?

Some of that though sounds like a vacuum leak, or some other problem

 

[lolford]

It sounds like your assuming it's transmission related but it sounds like the throttle body needs cleaning.

I have done that with contact cleaner. Made no difference sadly.

 

[lolford]

I don’t think convertor. Can you check trans oil level?

Some of that though sounds like a vacuum leak, or some other problem

I checked it cold and it looked ok, I did see some metal on the dipstick when I wiped but I heard that's normal.

 

[Warstud]

I have done that with contact cleaner. Made no difference sadly.

Contact Cleaner is an electronic cleaner. You need Throttle Body Cleaner and may need to remove the throttle body to do it right.

 

[lolford]

Contact Cleaner is an electronic cleaner. You need Throttle Body Cleaner and may need to remove the throttle body to do it right.

Whole throttle body was taken out. I checked and it actually was MAF cleaner if that's ok.

 

[Warstud]

Whole throttle body was taken out. I checked and it actually was MAF cleaner if that's ok.

It's ok as long as it removed the carbon. Was it dirty ? How is the idle now ?

 

[Greasymechtech]

I would drain/refill the ATF and verify proper level. If that doesn't help, you have bigger problems and would definitely be patient and baby it.

You can avoid the thud into driver from park by keeping your foot on the brake pedal for a few more seconds.

There should NEVER be ATF metal on a dipstick. Post a picture of the fluid 'metal' on the dipstick.

 

[Marcozi]

I bet the problem is in the power brake vacuum system. I sounds like you're getting excessive air into the intake system. The brake booster could have a leak or the 1-way valve on the vacuum hose may be bad.

 

[Warstud]

Whole throttle body was taken out. I checked and it actually was MAF cleaner if that's ok.

Did you resolve the problem ?