My freinds 3.0 v6 jags battery was flat and was removed for charging,when replaced the car ran rough, even after a good run it would,nt clear,and runs even worse when wet.he has been told that the engine managment would reset it self after a good run, but as yet this has not happend,can you help.

Have you actually checked fuel pressure, and the output of the coil ?
How good is the cap and rotor ?

Fill up your gas tank and ad a bottle of Lucas gas treatment/lube to the tank, be sure it's the treatment in a little clear bottle and not injector cleaner. After you've added the gas and treatment drive the car, with the head, driving lights, radio, heater, etc. all turned off. It may take ten miles or more but the check engine should go off and car will run normal. NOTE: Never jump start your car or use it to jump someone else's without referring to your owners Manuel.

Replacing the fuse the first time was the right move, becuase it could have been a fluke that it blew. Replacing it again and again was not! You should have found out EVERYTHING that the #2 fuse controlled and verified that the components weren't pulling excessive amperage (shorted condition). By replacing the fuse over and over, you might have made the problem worse by subjecting good components to something that was shorted.

BTW next time pick the oldest guy at autozone to help you, if the counter help knew their stuff they would have told you the same thing I just did!

Sounds like you changed the part that failed but did'nt change the part the caused the part to fail. the spark plgs wear out and need more power to fire as they wear out as do the old plug wires 87 is a long time ago and some are still running with the orginal parts (their that good) change all the parts at once ( plugs , wires , cap and rotor aand now again another coil) and you'll be back to going. remanber that low voltage will kill everythig and some starters will crank when the voltage is too low for anything else. fuel pump and the spark need good voltage to run and the starter may still turn the motor at very low voltages. check the battery and the charging system. You may try to just jumper to another car ( so the voltage is known good) and if it runs OK you are finding and testing battery and charging system parts.

First try and spray down the spark plug wires with some water from a spray bottom and see if the start arcing (you must have the truck running at all times to test this). If not that then clamp off the return fuel line and see fi anything vchanegs. let me know from there.

The rough running should have caused the check engine light to come on. It would be a good idea to goa ahead and scan the engine for trouble codes. The rough running could be a number of things. The codes would help us pinpoint the correct part ot replace, rather than start replacing parts until we get lucky and hit the right one. That could be very expensive.

USE THE MORE EXPENSIVE FUEL INJECTOR CLEANER , CALIBRATION NEED ON NEW SPARK PLUGS AND U WILL SEE THE DIFFERENCE. AVM([email protected])

Your electronics won't work properly if voltage is low. Charge and load test battery to make sure it's good, then check charging system to make sure it's operating. Once that's squared away you can diagnose running problem if it is still there.

Hi Clyde

Expect you have it running by now, as I see this was posted 2 March ?

If not......

Charge up your battery, and heavy discharge test, suspect you have short in the plates.

If OK, jump start with a set of proper heavy duty jump leads.

Good Luck !

A FixYa would be nice...Thank´s......John.

This could the problem with battery as it could be dead get the battery check if it less then rated voltage then its dead and replace the battery ....