Bucking at 1200 RPM when Warm

[Boaf 32]

1. Stangers,

I have a 2001 Mustang GT with 92,000 miles, SOHC that has a bucking problem. The sympton: After warm, cruising at 1200 to 1300RPM, 40 - 45 MPH the car, when pushing gently up a hill or on the accellerator produces a bucking, almost a skip in what appears to be the ignition.

What's been done:

1. I have replaced the transmission fluid and filter (was never done)
2. replaced fuel and air filters
3. Replace all spark plugs and all coil over plugs

The OBD reads 0 codes. The only other things I can think of that may cause this type of bucking are:

1. PCV, (which I'll check for vacume and voltage);
2. or something I noticed: 2 of the red rubber insulators that sit inside the sockets of the EFI connectors are missing. Maybe thay are somehow arching, but I don't know.
3. TPS not working correctly, but that should through a 122 code and I have no codes showing.

Does anyone have any ideas?? I appreciate it, thanks!

Bob

 

[trombonedemon]

You might wanna get a compression check.

 

[Boaf 32]

Another option, yes. I have the tools and will confirm. Checked the wiring looms and believe I found a compressed wire that may have caused the problem. Repairing and checking.

 

[trinity_gt]

You may want to verify that the MAF is clean by using a dedicated MAF cleaning spray on it.

Another thing that can cause this is excessive EGR flow. The valve can stick due to carbon deposits building up around the plunger.

 

[chasM]

Two other likely causes are a vacume leak or a bad coil over insulation boot. The latter often throws a code(300 to 308). I had a vacume leak that did that exact same thing you discribed and never thru a code.

 

[chasM]

Two other likely causes are a vacume leak or a bad coil over insulation boot. The latter often throws a code(300 to 308). I had a vacume leak that did that exact same thing you discribed and never thru a code.

 

[chasM]

Two other likely causes are a vacume leak or a bad coil over insulation boot. The latter often throws a code(300 to 308). I had a vacume leak that did that exact same thing you discribed and never thru a code.

 

[Boaf 32]

Resolved! Issue was bad wire!! If they are all that easy....thans everyone. I did check compression, EGR, and leaks! all good

 

[trombonedemon]