Loss of power during acceleration

[lurch]

I am experiencing occasional loss of power when accelerating. Mostly when towing but occasionally also when not towing. There are two different scenarios I am experiencing.

The first one is transmission related. When I start to accelerate, the transmission tries to downshift, misses the shift, and goes to neutral. It will not find a gear until I let off the gas for 5 - 10 seconds.

The second, I think, is an engine miss fire. When I start to accelerate, the engine cuts out and goes idle, I lose all throttle response, and a wrench appears on the dashboard with the text "see manual". Again I wait 5 - 10 seconds to get throttle response back and can drive on.

Often this will occur on a grade while I am towing and in traffic, so it feels dangerous and nerve-wracking when it happens. I did a 2,000-mile tow this weekend and had two missed shifts and one engine miss fire for a feeling of how often it happens. No codes are thrown and it does not happen frequently enough for a mechanic to recreate. Has anyone else had similar issues and fixed them?

 

[Soliyou]

Yes, for the first issue. It is the known neutral out condition. There is a TSB discussed here on this forum. The search function can easily get it. Bottom line, there are several internal issues that can cause this. The easiest of which is a faulty separator plate in the valve body. This particular issue will not require dropping the transmission. However, other causes may require dropping it.

The second issue seems like a faulty electronic throttle body. Since it happens frequently, I encourage you to download Forscan or use a code reader with live data and look at throttle PIDs while this is happening.

 

[lurch]

I got the work scheduled for the TSB and I have Forscan. Any recommendation on what PIDs to record? It goes by very fast and only happens once a month or so. I would want to set up a log to run when I am towing to hope to catch it.

 

[96blackstang]

So I have had this happen over the last year just trying to get on the hwy or trying to accelerate to get over on the hwy. Of course the Ford dealer cannot recreate. It reminded me of when my 04 cobra would have traction control kick in and cut off power to the rear end. But this isn’t that.

Have you noticed when it happens an almost rock tumbler noise coming from the transmission area under the dash? I’ve only had the lights a couple of times and of course nothing will come up on the code scanner. One instance I had it happen about 8 times while in traffic.

It’s currently at the dealer for the radio module again which that part is on back order and the loss of power issue so I’m having them check for that TSB y’all spoke of.

 

[lurch]

So I have had this happen over the last year just trying to get on the hwy or trying to accelerate to get over on the hwy. Of course the Ford dealer cannot recreate. It reminded me of when my 04 cobra would have traction control kick in and cut off power to the rear end. But this isn’t that.

Have you noticed when it happens an almost rock tumbler noise coming from the transmission area under the dash? I’ve only had the lights a couple of times and of course nothing will come up on the code scanner. One instance I had it happen about 8 times while in traffic.

It’s currently at the dealer for the radio module again which that part is on back order and the loss of power issue so I’m having them check for that TSB y’all spoke of.

Yes, a few times I have had the rock tumbler noise but not always. I took it in for service, and the transmission tech said that there is a known defect that causes metal-on-metal wear. The metal shavings loose in the transmission are occasionally blocking valves and causing the symptoms I stated above.
My transmission is getting rebuilt per the TSB next week.