So it's not a mustang but you guys will be familiar wit it, my wifes car is a 2000 Explorer 5.0 and has some issues nothing dramatic but I want it fixed before we head out on vacation, it has a stumble or flat spot under hard acceleration, it seems that if you press the pedal past 1/2 way it will stumble and recover and accelerate like normal. This has been going on for about a year, and have discovered if you accelerate slowly or gradually like a normal person would leaving a stop light it has no issues.
So yesterday i got access to a scanner and checked some things out, and found the longterm fuel trim a little higher than I like around 10% and the short term around -1%, the O2 sensors are working fine, and cats seem to be working as well, no codes or CEL.
The timing on the other hand is an issue, under hard acceleration and when the stumble occurs the timing will drop from its current advance curve down to 0 to -1 and then recover and continue along the advance curve.
What can cause this, Knock Sensor maybe?
So yesterday i got access to a scanner and checked some things out, and found the longterm fuel trim a little higher than I like around 10% and the short term around -1%, the O2 sensors are working fine, and cats seem to be working as well, no codes or CEL.
The timing on the other hand is an issue, under hard acceleration and when the stumble occurs the timing will drop from its current advance curve down to 0 to -1 and then recover and continue along the advance curve.
What can cause this, Knock Sensor maybe?
