Hey guys I recently bought a 1990 Cherokee Pioneer with a blown motor. I found a 97 Grand Cherokee with an inline 6 and put that motor in my Pioneer. I got everything out back together and when I start the jeep it runs for about 5 minutes and starts puttering out and dies. Any ideas on what could be the problem? Is this common? Vacuum lines? Thanks for the help in advance!

 

I would check the fuel pressure at the fuel rail. The fuel pump could be failing to provide enough pressure

 

Fuel pressure is definitely a suspect. Throw a test gauge on and see what happens when the engine dies.

What happens after it dies? Can you restart it again immediately? What happens if you do, does it run another 5 minutes and then die again?

Have you checked out Cruiser's site for Renix-era XJ's? If not, I would do so immediately and get started on doing the many tips outlined. www.cruiser54.com

 

Yes it will start up immediately after it dies and then same thing, runs for a bit and dies. I will check the fuel pump. Any other recommendations would be helpful as well. Thank you.