Atraxtj

Alright I've read a bit and I'm led to believe my cat is clogged, but the way my jeep acts kind of makes me think in another direction. First off I recently bought this jeep and it's a 2000. The motor was replaced with a 94 block and he says the head is a 2000. It does have a coil pack and two cats on the manifold. Under the oil cap is milky. I'm thinking a blown head gasket, but the engine doesn't over heat. Just a little over 210. Now at idle, she purrs. Doesn't skip a beat or miss. when I rev it up it Does the same thing in park. Everything is fine. When I get on the road she has nothing. Rpms ride up to 2000 taking forever to get there with little to no power. It will shift and everything. Sometimes it will buck a tiny bit and the engine light will flash. Only other time I've seen this is when my buddies threw a rod. I'm a little lost and would like some input on things I can try. Thanks!

Oswalla

Cat can be checked easily enough. Hook up vacuum gauge to a manifold port, take idle reading then a reading at 3000rpm. Clogged cat will read lower vacuum at 3000rpm than idle reading. Or take out O2 sensor up stream of cat and see if problem goes away. Or grab the exhaust after cat and before cat, upstream side of cat will be significantly hotter and may require a trip to er, hehe.

No codes ? O2 codes maybe ?

Winter condensation can account for a oil CAP being milky, is the oil itself milky ?

A compression test will tell you a lot, cheap too.

Alex V.

Check all the areas related to its state of tune or tune-up - air cleaner, spark plug condition, etc. White buildup under the oil cap can be normal, but if the oil itself isn't any of the normal oil colors then there is coolant getting into the oil. If the HG was blown, just not losing massive amounts of coolant or overheating, most likely its most severe feedback (before going boom) would be a bad miss on one or more cylinders - but if it runs smooth most of the time, just really low power, its not likely to be the head gasket. Sounds like something a clogged cat could certainly cause - Oswalla's processes to troubleshooting that are good.

diskman

Replace the fuel filter?

Atraxtj

Hmmm interesting. I think I'll try all this tomorrow and see if anything changes. Thanks for the help!

Atraxtj

Alright some more info that might help. When I first start it cold I can drive it fine with power and everything until it gets warmed up. After that It feels like it's dying and doesn't have any ***. There is also a high pitch squeal when I try to accelerate more. Sounds as if it's coming from the driver side firewall area. I also smell antifreeze, but I might be crazy. Any other ideas before I try the previous options? I do not have a check engine light. It does light up when I turn the key so I know it's in there.

tjwalker

Do you mean the CHECK ENGINE light?

If so, even if the check engine light currently isn't on, there is a very good chance that you have a "stored code". Retrieving that code with a code reader or a scan tool might yield a very valuable clue.

Alex V.

A high-pitched squeal could be a vacuum leak, and it -could- cause this problem. With the engine running, move your ear(s) over the engine compartment listening for a sucking sound that shouldn't be there - if you zero in on an area, try slowly waving your hand over that area to try to hone in on exactly where it is when the sound changes because your hand is blocking it. If that gets you anywhere, then investigate any lines or hoses in the viscinity for vacuum leaks.

D1gger

You might try pulling all of the plugs and taking a look. My guess is that one of them looks brand new. If that's the case, you have at the very least, a head gasket issue. It's being steam cleaned by the the coolant.
Makes sense. Once it warms up, everything expands a bit, the leak opens up. Now you're burning antifreeze too. The milky antifreeze, the smell, etc.