I have a 1999 sport that has an off and on problem. Gauges go wild, voltage spikes then slowly drops off and there is a loss of power. The TPS was replaced but didn't help. Hope someone can help figure this out.

 

You have a lose ground I know I just paid $300 to have mine fixed. There are two main ground on the engine check those first. Could be dirty distributor clean that too, but its a ground.

 

I agree that this smells of a "flaky" ground issue. All signs point to it....

Grounds are too often overlooked and are the cause of many electrical gremlins. Refreshing grounds is NEVER a bad idea!

You can't just check or look at these grounds because a visual inspection can easily fool you. A small layer of corrosion can create a resistance path that screws up your ground. You must remove, scrape, clean until shiny the cable/wire ends and whatever they bolt to.

The one on the back corner of the head, and where it attaches to the firewall. Scrape the paint from the firewall. Best to replace that woven cable with a #4 or #2 gauge cable. You can attach the one end to the intake manifold if you would like.

Next go over to the engine dipstick tube stud. Remove the nut and clean the wire ends and scrape the block til shiny at the stud. Reattach tightly.

If you are so inclined, add at least a #6 cable from the negative terminnal of your battery to one of the bolts on your radiator support. Scrape the paint off first.

 

Update on this....took jeep in and had the grounds cleaned/replaced. They also found the alternator to be bad so we replaced it. HOWEVER, the original problem did not go away.

Note sure what to do next. New mechanic maybe? Anybody got any ideas?

 

i have a 98 sport and the same thing happens except all my gauges go haywire!it might be an electrical problem like on mine, i turn my headlights on and off a couple of times and all gauges are restored! i was told its my cluster, need to get my jeep re-wired or just my grounds.still troubleshooting........

 

Update on this problem.....did all the repairs suggested and STILL not finding the issue. We tried disconnecting the air-bag circuit on the advice of a dealer repair shop...something about a computer signal.

So far nothing works. Still have gauges going wild, check engine light on (and off) and a loss of engine power. Any more ideas out there?

 

altenator or belt snapped (but im sure you would have noticed that) start the jeep and unhook the battery... if it shuts off and dies then you need a altenator...

 

We replaced the alternator prior to the air-bag circuit try.

 

ah sorry i missed that post... maybe fried computer then

 

sounds like same intermittent trouble I have with my '99 Cherokee limited. gauges bounce back and forth and the cluster buzzes. now on occasion it will only start in neutral, maybe related? hope someone has a fix for us!