heatsoak? fuel pump? Please help!

[tn_outside2003]

I didn't say it had a cracked head. I said it had worn valves. I did not regurgitate ANYTHING. I posted MY experience. From MY real life. From MY jeep.

And he had a MISFIRE, and a ROUGH IDLE, and a long crank. It is a head. Dollars to donuts. And the POINT of the compression test is specifically to diagnose.

It is cheaper to have a compression test than to chase fuel pumps, sensors, coil packs, etc.

When the OP KNOWS that his head is not worn....THEN look at more esoteric issues like fuel pumps, sensors, etc. The 2000, 0331 head FAILS. In every jeep. He has a misfire....the number ONE REASON for a misfire in a 2000 jeep is a bad head. NOT fuel.

 

[tn_outside2003]

Oh--one more thing: IF you have a worn out head (and I don't know that you do...but I would start with a compression test)....the reason that I suggested getting a NEW head instead of rebuilding your 2000 head is because the 2000 heads are faulty. This is a well known issue. Search for 0331 cracked head. They cracked between the 3-4 cylinders. You can see the crack. It is obvious.

Chrysler changed forgeries to a Brazilian forge and they modified the casting. The new heads are stamped "tupy" on top of the head (under the valve cover). In fact, the Dodge hemi heads are still being produced in the same forge. I absolutely WOULD NOT spend a single penny rebuilding a 2000 0331 head. It will crack if it ever gets real hot, or if anyone ever tightens the head bolts anything other than God-perfect, or if it gets angry, or if the full moon and the Solstice and western wind blow at the same time.....

Don't rebuild a 2000 0331 head. Get a 2002 or later Wrangler head and have it rebuilt.

IF you have low compression. Which you might not.....

 

[blondejoncherokee]

After you are able to verify that the pump is good, injectors are good, (also replace the fuel filter) and if you are still having the symptoms (my buddy was getting random cylinder misfires with heat soak issues on his 2000)
then there are 3 cheap and easy things you can do. Wrap the fuel rail with heat tape, slap on some hood vents, and if you have the pre cats, then there is a crazy good chance both flanges are loose, causing hot exhaust to make heat soak worse, or pretty much cause it entirely. try to start after stopping, no dice. if it did start, it would run like crap. let it sit for 30 minutes plus, starts right up.

We did the first two years ago on his(fixed most of it) , only recently did we find the pre cats where loose as hell, we actually suspect the pre cats being loose could have been the issue all along.


I also agree with the BG44K (well, just a bunch of good fuel system cleaner that you prefer)

Although it never hurts to check compression, I highly doubt bad rings or a sticky valve is causing the slow start as described, but It doesnt hurt to spend 20$ on a compression tester and do it real quick. I wouldnt pay a shop to check compression, its too easy to do yourself, and now you have a tool. Although I am betting your compression is good.