This is my first time posting anything anywhere so here goes. I own a 2000 XJ8 with 71,000. The car has been great to my wife and me until recently. A while ago the transmission went so we replaced it and on the way to the shop it busted the plastic thermostat housing thus overheating the motor. I made it to the shop but not without getting coolant everywhere on the motor. I then had the trans rebuilt and got the car home. On the way home it ran rough but I attributed it to the overheating . I repaired the part but I still cant get it to run well. the parts I replaced are endless.New battery, coil packs,plugs,cam sensors,fuel filter,gas cap, MAF sensor,and Im shure I have missed a few. my symptoms are as follows. car will not go over 50 without engine shaking. at times it runs so smooth you cant hear it and most times if you listen to the exhaust you can hear it puffing like a misfire.The car has been to the dealership but they concentrated on everything else but my engine problem at the cost of $300.00 .I have been to 3 other shops but nobody wants to work on them or does'nt have enough knowledge of them to diagnose the problem. Can it be bad injectors? would'nt the engine run bad all the time if it was. like I said sometimes the car goes like there is nothing wrong, I mean it goes like a rocket,but most times it sputters and has a hard time accelerating. It does not burn any oil,does'nt leak water or loose it in the oil.no vac leaks that I can find. I really want to keep her but I want to be able to drive it like I used to . any help is welcome. thank you.

 

Welcome to the forum GUYC,

Overheating is never good news on the V8.

I've moved you post from General Tech Help section to X308 section where you'll get a wider response from members with the same model.

When you get a minute, please follow this link New Member Area - Intro a MUST - Jaguar Forums - Jaguar Enthusiasts Forum to the New Member Area - Intro a MUST section and post some info about yourself and your vehicle for all members to see. In return you'll get a proper welcome and some useful advice on posting to the forum.

Graham

 

Did u get used coil packs? These cars are very sensitive to water. I cleaned my engine once and a lil moisture got
In the coul packs...same symptoms. Took a few weeks to dry it all out. It sounds like something has gotten wet. Let it dry out. Leave the coil pack covers off for awhile. Also check to make sure the little plugs for the coil packs aren't loose. U could hav a bad coil pack still that is intermittently acting up. When it's running rough unplug and re plug the coils one at the time and try isolating the bad one.