eyesac said:Hello, I have a 2001 XJ 4.0 and have an engine misfire (cyl #1 / p0301). I've replaced the plugs, but I suspect the coil (pack/stick). Does anyone know of a way to test this?
Thanks!
Not likely the coil pack since there are 3 coils within it and each feeds 2 cylinders unless it's the contact to the plug. What plugs are you using?
Never use Autolite plugs.
eyesac said:Ok fine, but that's not the problem. I changed the plugs and the code (and misfire) remains. So I guess there's no way to test the coil...
Is your jeep actualy missing all the time
IGNITION COIL RESISTANCE - 4.0L ENGINE
PRIMARY RESISTANCE 21-27°C (70-80°F)
0.71 - 0.88 Ohms
COIL RAIL - BLACK 4 WAY CAV CIRCUIT FUNCTION
1 K19 18GY IGNITION COIL NO. 1 DRIVER
2 A142 18DG/OR FUSED AUTOMATIC SHUT DOWN RELAY OUTPUT
3 K17 18DB/TN IGNITION COIL NO. 2 DRIVER
4 K18 18RD/YL IGNITION COIL NO. 3 DRIVER
eyesac said:I know how to test the resistance on a "normal" coil, how do I test this stick? Do I just test #1,2,4?
LiamN said:Going through the same problem.
there was a TSB on the coil pack for 2k-2k1 4.0L engine... it is as follows:
Call up a jeep dealership and have them look up the TSB by name, not by that number.. anyway here's what i've found out:
- TSB #0900303 -- 4.0L MULTIPLE CYLINDER MISFIRE. *TT (NHTSA ID #10003538, AUGUST 01 2003
1) the misfire is generally on cylinder 3
2) it is caused by a sleeve causing a faulty connection to the plug
3) the sleeve is easily repairable by simply buying a new sleeve from the dealer.. 2 bucks.
My xj is all out of whack right now.. idling rough, loss of power, and sputtering like a a badly shifted standard transmission between 2500-2700 rpms.
coil pack is suspect, hope i was able to help