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Hey all! So I have a few more issues with my 99 4 door 5 speed


Today I went on another long long drive and it did great! Problems occurred but performance wise it stayed just fine.

I climbed pikes peak (14k feet) and as I got down towards the bottom (low gear, conservatively. Not screaming) and turned around and went back up hill to catch a turn I noticed it DUMPED so much smoke out the tail pipe and I lost quite a bit of oil. I figured I'd do a compression test and replace the PCV valve (which doesn't externally look wet) and then maybe move onto possible exhaust valves issue. It only seemed to do it after going down hill for a while in low gear then putting it under a load back up a hill.


My temps never quite seem to get to half way always just below when it's nice and hot and running (it runs cool, I need to try a yota t stat this time).

But when I parked at the top of pikes peak and came back to the car I notice some coolant on the ground from the overflow bottle. It was in fact BOILING in the overflow... I hope this doesn't point to a head gasket issue.

Lastly I have an oil leak. It seems to come from the timing cover. Do cam seals tend to leak on these? Am I looking at doing a head job? Thanks! I had also noticed a decent amount of oil on the ceramics of my plugs when I changed them out. So it looks like a valve cover gasket is in order as well.
 

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Well, you certainly put an old engine thru some extreme conditions both with the altitude changes and climbing and descending the mountain. Climbing will obviously tax the cooling system to the max especially at relatively low speeds w/o much air thru the radiator. I don't know the exact numbers but the boiling point at 14K altitude is well below 212F. Hopefully those factors and a fairly diluted coolant mixture accounts for the boiling.

The oil loss is a sign of the compromised condition of the rings and valve stem seals. While descending, in low gear for engine braking, the engine is running at high intake vacuum for an exaggerated length of time compared to normal driving. The small amount of oil that gets sucked past the rings and seals on deceleration during normal conditions accumulated significantly on the descent. Then upon heading back up it all gets burned and blown out ASA you accelerate, accounting for the smoke and oil loss.

Your leak past the camshaft seal is another indication of deteriorating seals.

You could drive it under normal conditions for a long while w/o too much repair or replace the cam and valve stem seals to reduce the oil loss. I'd do a compression test to check the piston rings and valves but I see at least the head coming off, new seals and decarbonizing the valves in your near future if you plan on keeping the car.
 

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Fantastic reply thank you. I'm going to do a compression test first and foremost to rule the Rings out hopefully. Then I'll pull the head and send it out to get rebuilt and get a new timing belt kit with water pump oil pump cam and crank seal. Thanks!

Also its not straight coolant there is eater I'm the system so that makes sense
 

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The time I went to the top of Pikes Peak, I took the train, it was fun.
Many cars have a small overheating problem on high passes, but usually the problem is mostly driver error and not mechanical. But it is easy to be excited up there looking at the view and not thinking about the engine. If the road up Pikes Peak is like most you have a long slightly hard pull to the top. So the head, pistons, valves, and oil are pretty warm, but the cooling system can handle that quickly so it doesn't register hot. Often you get lucky and pull right into a perfect parking space, then the engine gets unlucky as you turn off the cooling system before it can dump the excess heat. At 14,000 feet the boiling point is down to about 185 degrees and the pressure cap is 9 pounds at sea-level. If you do lose any anti-freeze, please clean or dilute the spill if you can, it is deadly to the small critters that live up there.

The valve stem seals can be replaced without removal the head. The seals on mine are bad and I get a good puff of smoke on cold starts and I usually have to add a quart during the 5,000 oil change cycle, but the engine has no visible leaks.
Mine doesn't smoke after a long downgrade and after reading this post I wonder if one of my odd driving habits may be helping me. When riding a gear down a long grade I don't like the sold of the high vacuum on the engine, so I tend crack the throttle open just a little while cruising down the grade. I just thought it was from many years driving diesels, but it might help.

The camshaft seal sits under the upper timing cover, so I would look for a leak on the timing cover gasket first. At least for a leak on the back left part of the engine.
 
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