i have been developing issues with the power of my 97 mustang 3.8. over the past few daus I developed in imbalance in the motor at idle where my fuel trims where reading -20.31 and +32.81 on driver side and passengers side respectively(Not 100% sure if its releated), but recently it has turned into a castrophotic issue where my car cant go uphill without loosing 20 mph in speed. im not sure what the issue is. i just replaced the ignition system, including, ignition coil, plug wires, and plugs. also recently changed the fuel pump. Sadly it changed nothing. im current guess is somehow my timing is off, but i am completly lost on why that would happen, seeminly so randomly as well. i also wonder if my harmonic balancer could be failing and causing issues. i know i have vaccum issues, but surely it wouldnt be this major if my EGR failed. also am curious about the crankshaft postion sensor, but if i am not mistaken that would throw a code. Curious for any tips im lost as can be.

Thank you!

 

If you have a OBD reader, look and see if there is a code which did not turn on the MIL. I'd also be looking at the oxygen sensors, code or no code. And you didn't mention the mileage. After all, nothing lasts forever!

Your 97 is one of the first generations of OBDII, and not everything turns on a code. Even later models with the latest diagnostics don't always code out especially during closed loop. If you have an inexpensive code reader, it might not be able to read some codes. It might behoove you to pay your Ford dealer to use their code reader.

 

It has 96k miles, i have no obd codes currently, and its making a sound almost as if the exhaust and intake stroke are swapped when revving it slightly. i have replaced downstream 02 sensors about 2 months ago, because one of them melted to headers. i also just did the fuel pump last weekend it lasted about 60 miles before this has started.

 

Maintained properly, the 3.8L EFI V6 should last well past 96K.

I don't understand, when you say it sounds like the intake and exhaust stroke sound like they're reverse? This could be caused by the EFI as it and the spark are controlled by the same EEC (could be version 4 or 5 based solely o the year). As I said, sometimes it is best t pay the dealer to do a real scan to see what they see.