Hello I have 1998 Jeep cherokee xj 4.0 I6.
Ever since summer 2019 my Jeep will 8/10 times lag and sputter when I startup. I checked and this happens in neutral too, because initially I thought the trans might be slipping. I found that the problem goes away after 5 sec -1 min after it starts, then the car runs perfectly fine. Also the problem seems to go away faster if I floor the gas pedal. Sometimes I can hear a popping noise coming from beneath the car when the problem acts up harder.
This all seems to point to the fuel pump, oxygen sensor, or the fuel injectors - at least to my understanding of it.
Can anyone tell me if I’m on the right track or what they think it is?
-So far I have replaced the cap, rotor, spark plugs, spark plug wire, and air filter-
Thank You for any and all advice!!
Ever since summer 2019 my Jeep will 8/10 times lag and sputter when I startup. I checked and this happens in neutral too, because initially I thought the trans might be slipping. I found that the problem goes away after 5 sec -1 min after it starts, then the car runs perfectly fine. Also the problem seems to go away faster if I floor the gas pedal. Sometimes I can hear a popping noise coming from beneath the car when the problem acts up harder.
This all seems to point to the fuel pump, oxygen sensor, or the fuel injectors - at least to my understanding of it.
Can anyone tell me if I’m on the right track or what they think it is?
-So far I have replaced the cap, rotor, spark plugs, spark plug wire, and air filter-
Thank You for any and all advice!!
Get the codes from the Jeep, then you'll know if it's a sensor issue. Get hold of a fuel pressure gauge and attach it to the schraeder valve on the fuel rail.
Fuel injectors are harder to test but usually pretty reliable.
Fuel injectors are harder to test but usually pretty reliable.
Ok I got it scanned and threw no codes. Guy at the autozone said something about it only sending 1 misfire report and 3 were needed for a check engine light which would provide a specific code.