First of all, I don't know what is wrong. My 2000 XJ is running perfectly, oil pressure is normal (30 at idle up to 50 under acceleration). My oil smells fine, looks fine, feels fine, though it is DRINKING coolant. It disappears. My oil cap has this brown frothy mess on it, but no where else I can see in the engine itself. I dropped the oil from the dipstick on the exhaust mani and it smoked, didn't just sizzle like water. My exhaust leaks water, but every car I've ever driven, and seen does too. The exhaust doesn't smell like fruit loops, but its a faint white. Here's the deal, none if this happens when its hot outside. No froth, no white exhaust. Also theres some rust looking mess in my radiator and on the cap. I think its from tap water. I had the head repaired, not too long ago, roughly 10k, and resealed the rest of the motor.

So heres my problem, am I freeking out because its cold here? My other car did the same thing in the cold, so I don't know if I'm crazy. But its always been drinking coolant. So is there a leak thats only from driving? It doesn't leak when its at cold idle in my driveway. Any ideas!?

 

Doesn't sound good. Could be a head gasket or cracked head ('00 and '01 is sorta famous for cracked heads). You need to do some diagnosis (compression test, pressure test cooling system, etc).

 

Well, if you are losing coolant from a closed system than, yes, you have a problem regardless of ambient temperature.

 

sounds like a cracked head bro, you xj's year is notorious for this issue, check you head gasket, coolant is leaking into your oil making that frothy look you are talking about. pull the valve cover and look at it, you'll definitely notice one or more cylinders looking in bad shape compared to the others, hope this helps

 

Well guys here's some news, I bleed the radiator and refilled it, its been two weeks and it hasn't lost any coolant. And the froth stopped on the oil cap. The heads were cleaned and all, nothing. We found a leak in the radiator, that's where it was going. So looks like we dodge a big one haha. Time to keep building!

 

Keep an eye on it.. You have the 0331 head..prone to crack.

 

great to hear, always good to have a minor problem easily fixed. like XJ88 said just keep an eye out and try upgrading your cooling fans, and routine maintenance to make sure your head doesn't **** the bed when you need her the most