i get a ticking only under accleration. have not determined if it is warm or cold engine sensitive. unsure of where the sound is coming from. and it doesn't always make the noise when accelerating. thoughts? 1990

 

Sounds like the beginnings of a cracked manifold.

 

U-Joint? Motor Mounts? Could a bad mount let the fan hit something? (it can on a 66 Ford F-250 with a 240 six) You might open the hood and power brake it a second. Easy check. If the engine gets up to leave, BINGO.

 

Or once I put a starter bolt in there that was a tad too long and would barely touch the torque plate accelerating. Took a while to figure that one out! The end of the bolt was "burnished". Still has a small stack of washers.

 

sounds like i got the weekend planned to check out your ideas, cold beers, music and exploritory wrenching.

cracked manifold? which one. intake or exhaust?

 

Flex plate bolts loose? There are tons of possibilities.

You need to get under/around it with your ears, preferably with a piece of hose/screwdriver/stethoscope and determine the source/area of the noise.

That will help us to help you as we can't hear the noise from here.

 

Agreed on the hose, and I'd bet slick is thinking exhaust. Course that's where noise comes from. Also I've had the header pipe flange there leak. If you power beak it it duplicates accelerating down the road. (in first). BE CAREFUL!!! E-Brake, block the wheels, foot jammed on the brake!!! Park the front bumper 1 inch from a tree!! Bad things can happen too fast. I don't think it's a good idea to do that long. Something must be getting hot. 10 seconds, then wait, maybe 20. And wouldn't do that more than a minute or two.

On mine I was with cruisers idea. Somehow someone got a flex-plate bolt in there crooked. (really fun). While I was swearing at that is when I found I had put in a starter bolt just long enough to contact the flex plate on acceleration.

 

That would be the exhaust manifold, and the easiest thing to check. Put your hand near it and feel for the leak. Cracked exhaust manifold is a chronic XJ issue.