[jtec]

misfire is BASIC automotive.

jeep is STOCK no aftermarket BS, programmers, chips, lower thermostats, miracle parts?
Any other codes ANY ?

Do you have a SCANNER - able to see live data? makes this a fast snapshot.
That will give us a fast big picture.

IF no then basic tests.
Fuel pressure PSI?
Spark plugs - firing - plug appearance, brand and #.
compression test.

 

[Shahabuddin]

My absolute sincere apologies for the late reply, all the shop says is that there isn't pulsation from the ecu to the no. 6 fuel injector...
My question, is it true that a weak engine with lower than normal compression cause the ecu to inject more fuel?
The vehicle is factory stock.
OEM champion plugs not even 5k miles on them.
The cats is also showing signs of being burnt due to over fueling. It actually spits out unburnt fuel when warming up from full cold temperature.

Warm at operating temp compression test is 140 PSI which I think is a bit low but I could be wrong.
As of my last check at the shop the ignition was on spot for all cylinders and that's all that I could look through because I don't have a scan tool of my own...

misfire is BASIC automotive.

jeep is STOCK no aftermarket BS, programmers, chips, lower thermostats, miracle parts?
Any other codes ANY ?

Do you have a SCANNER - able to see live data? makes this a fast snapshot.
That will give us a fast big picture.

IF no then basic tests.
Fuel pressure PSI?
Spark plugs - firing - plug appearance, brand and #.
compression test.