Hello. I have a 97 xj with 200k miles. I've owned it for 4 years and it's generally run good!

This past weekend I switched out the header as it was cracked and did a heavy cleaning of the intake. I've ran the cars a few times this week but yesterday really got out and about on highways, etc.

I was on the highway when I noticed power was losing. I pulled over in a gas station and the engine sounded like it was missing. Check engine light popped up shortly, which I didn't check the code.

Luckily there was a mechanic a mile away which I hobbled over to and they check it out. He said they did a compression test with cylinders 1-3 having psi +-50 psi and the last 4-6 having 70-80 PSI.

They basically recommended an engine swap but weren't pressuring me to do this.. Seems odd that the car was running fine a day or two ago then all the sudden a bad engine?

Any advice would be appreciated!!!

 

Wondering if I blew the head gasket somehow with the changes I made??

 

Changing the header should not have done anything to the head gasket . 1st you need to check what code you have it could be a problem with the wiring for the injectors or something like that .