Alright so I bought my 95 xj not too long ago. It runs fine could be better but it's drivable. But the thing is that it won't rev past 3k rpm. It's like it has a rev limiter set to that. I drive it an hour and a half home with it not over heating or anything. Also I've never posted on here. So which ever way y'all can contact me with questions or whatever it will be greatly appreciated!!

 

There are two things I can think off to check one is the catalytic converter it could be getting plugged and second the fuel pump it may not be giving the engine enough fuel .

 

I would start by checking fuel pressure

 

Did you do a tune up when you bought it? Replace fuel filter, plugs, wires, cap and rotor, and air filter? I would recommend all of the maintenance items, so you know their condition and can rule them out. Then start from there.

 

Last night I was messing around with it put some seafoam and a new tps on it and just let it so it's thing then about 5-10 mins later i noticed that the exhaust manifold was cherry red so I cut the cat off but it didn't solve the problem

 

Did it do this before using the seafoam? Ive never used the stuff, but something is causing it to run lean. Could be in need of a tuneup and nothing more if youre lucky. Do you have good spark at the ignition coil? Any vacuum leaks? For all i know the seafoam dislodged some dirt that got picked up by the 02 sensor, causing it to lean the mixture. Or the sensor simply didnt like the seafoam and gave it a belly ache, so to speak. No clue.

That would be on my list as well.

 

I have bought a tpi map sensor o2 sensor and a complete tune up distributor wires plugs fuel filter etc. Still have the same problem. The cat was a problem but it just made the problem a little better instead of fixing it entirely. It has a really hard start and sometimes it seems like it's running off of 4-5 cylinders then I'll give it some gas and it'll quit. I still can't exceed 3k rpms bc of the "reset rev limiter" so to speak. I've been looking around on these forums and some people have said that if my exhaust manifold was cracked causing it to head up my head causing my valves to burn out

 

Have you checked the fuel pressure, or for any vacuum leaks since chaning all that stuff? What did the old plugs look like? Has the distributor ever been removed or replaced that you know of? It may have been stabbed incorrectly.

 

Fuel pressure is 34-36 lbs of pressure. And everything with the distributor is aligned right as it sound be. I have noticed a date that's on the computer. My jeeps a 95 and it says 93. I don't know if that could have anything to do with it or not.

 

I will upload a video to YouTube to show y'all what it does. It's like something I've never seen. I'll add the link when it's uploaded.