Hello all, as many know I am completly new to the Jag world and I ask what some may consider stupid questions. I'll just jump right to it 1976 XJ-S, it sat for probably close to 4 years never started or drove. I had quite a few wire issues but I have gotten it started and now the fun. Idle and while in park the engine sounds just like I would expect it to a little smoke which I would relate to sitting for so long the problem is once I pull it in gear the thing barley wants to move I did pull it in and out of my drive and around the culd-a-sac, drove maybe a total of 100 ft. I will obviously be changing all fluids (oil, trany, rear end, and filters and lubing the joints real good before actually driving it. Could this be my only problem?? does the car just need to be ran real good? My next question is that the exhaust is with out a doubt running at 2 different temps and pressures. The temp gauge never even really reached the "N" and the banks feel the pretty close to the same temp. I do for sure have a vaccum leak to locate and am aware of that. Any suggestions, comments, or advice will be MUCH MUCH appreciated. Also would it be ok to drive the car about 1 mile (never over 30 mph) to get it somewhere to lift the car off the ground (a shop I have access to a lift at.)

Submitted by SC20-30420CJ on Thu, 05/08/2008 - 19:33

You can disconnect the exhaust at the down pipes and run the engine to see if performance improves. If it does, that would point to a clogged cat. The engine will run fine without them. My UK spec V12 has no cats. You have Lucas-Bosch D-jet efi on your 76 and they seem to idle rich. Some black smoke from the tail pipes at idle is normal. That will clog a cat eventually.

Other points to check are:
The distributor mechanical advance. Pull the distributor cap and check that the rotor will turn about ten degrees, then snap back. If it won't move or is stiff, the advance mechanism is seized and needs to be cleaned up and re-lubricated.

Check the throttle linkage. I had a 76 once and the linkage pulled off the right bank. It would idle fine, but pushing on the gas pedal only opened the left throttle and it had little power.

Check fuel pressure. Low pressure can allow the engine to idle, but won't have enough to give you any power. You should have about 36 psi at the injectors. There are two fuel pressure regulators on your engine. Check the fuel filter. Is there fresh gas in it?

Change the oil before running it again so you don't circulate all that sludge up into the heads.

Submitted by marionandjohn@… on Mon, 05/05/2008 - 17:52

No bent pipes. Any suggestions on clearing or atleast checking the cat. My idea is to just get rid of the cats all together do I really need them? My state does not require emissions testing.

Submitted by SE98-32482CJ on Sun, 05/04/2008 - 16:02

Your different exhaust temp and vol sounds like a clogged cat or bent pipe --or both. If the engine was working properly it would pull through frozen brakes--but you may not be able to stop. CHANGE THOSE FLUIDS NOW!