mtyson

97' XJ Inline 6 AW4 4x4

I've got a lot of moisture from the exhaust. White smoke from the tailpipe, especially when cold and under load.

Engine seems sluggish.

I did compression test this morning, and all cylinders seemed OK.

Any leads where to look next?

tjwalker

1. Are you having to add coolant to the coolant reservoir? That would be a big clue.

2. Any check engine light? If so, pull codes for clues/guidance.

3. The compression spec for the 4.0 is 120-150 psi with no more than a 30 psi variation between cylinders. How does your compression testing match up to this spec?

mtyson

Yeah, they were all within spec... It was my first time doing it though, so maybe I missed something.

There is a code, key trick shows code 45... a mystery code on a 97 xj... I need to have it read at the part store I suppose.

Thanks.

jordan96xj

mtyson, #1 mentioned by tjwalker is probably the most important to consider.

Because the XJ exhaust is typically pretty wet, especially when the ambient moisture is high and the temperatures are cold. It will basically drip constantly when idling. Sometimes the white smoke on a cold day is simply the exhaust heating up the moisture that is condensed in it over night, causing it to leave the pipe as vapor, but then condensing again when it hits the cold air. This can persist for several minutes (8-10) while the motor and exhaust system are heating up.

So if you aren't loosing coolant from the reservoir, what you are seeing may be normal. Now if the exhaust constantly blows white smoke, or blows fresh plumes of white/grey smoke when accelerating, even after everything is well heated up...that is usually an indicator of bigger things.

Perhaps the sluggishness is something unrelated and more simple. When was the last time basics like plugs and wires (tune-up type things) were addressed?

diskman

Ya.. My 1999 smokes at idle too when it's cold out. Drips and leaves a puddle of water at the tailpipe. It's normal. That's why they make stainless steel exhasts. Combustion creates H2O. When the exhaust system is hot, the water doesn't have time to condense and simply exits unseen. At idle, the exhaust metal is cool enough to make things steam and drip water.

Check your coolant levels. A bad head gasket will drink coolant fast enough to notice it fairly quickly.

Compression test OK? Just drive it. Buy a cheap ELM code reader on Amazon for 10 bux and pull your own engine codes.

PatHenry

Sorry for the dumb question - but I saw this:

and was thinking, the acceptable range is only 30.. but it occurred to me that this probably is across ALL cylinders, right? How is it calculated? Sum of differences between each?

Bugout4x4

The lowest no more than 30 from the highest. But honestly... even that is too much for my tastes.

firebane

Generally 10% difference between each.