ViolentCrime

ok, here is what i got. i have a 98 xj with the 4.0l with 213k on the odo. the biggest problem with the jeep is the alternator. it is only giving off 12.75 volts instead or the 13.75v that it should. now the tricky part is, it will give off full charge at start up and 3-5 minutes after start it will drop off. now yesterday i had it running just fine with 13.75v for around 2.5 hours of driving (from springfield mo to tulsa ok) i hit a bump just outside of tulsa and it has not given out full charge since. now i have come to the idea that this is either the brushes in the alternator are going out, or i have a dead spot in it somewhere that seems to pop up when i hit a bump. now i have let it heat cycle 3 times not since and it will not kick back on line at full charge. so i can almost rule out the dead spot. now the really funny part is i have taken the alternator off of the jeep and tested it and it tested fine at both oriely autoparts and advanced auto parts. in fact i had them both run it 6-7 times each to try and duplicate a failure. and nothing. so if you have any idea on the this matter let me know before i just start swaping parts. part of me wants to thing its the computer (ecu) but i can almost rule that out.

and my second problem is when i turn on my turn signal my hazard lights flash once or twice and then it goes to the direction that i am signaling. it does not show it on the dash but i have been told this by a few different people.

if anyone knows anything about either of these problems any and all info will be helpful.

Abovetimberline

Pull your hazard and signal flasher out and see if the alt will put out full charge.

Throttle Jockey

12.75 is charging. if it puts out max voltage all the time it would burn itself out. if its been tested by two seperate auto parts stores multiple times and it shows good. i dont think you have a problem.

Jamie57

Check the grounds. All of them.The bump is the clue.

Throttle Jockey

couldn't hurt.

Willys55

Spot on.

Also check that the battery connections are good and clean and tight. should be running at 13.45 volts and 15 amps without loads(lights and A/c). As much as 14.14volts and 40+ amps with everything running