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Discussion Starter #1
I just inherited the family heirloom -- an 85 P-type with 112,500K. Almost everything is stock.

The engine burns oil through the tailpipe after excessive idling with city driving but, more of an immediate concern, is oil smoke from the engine after it warms up.

The smoke comes directly from the top of the engine, not from down below [please forgive my mechanical ignorance:(] and continues for several minutes after the engine has stopped. The valve cover gaskets have been replaced a few times and I'm hoping this might provide a quick fix for this problem.

Another disturbing facet is significant engine pinging when on the highway under very moderate climbs. When attempting steep hills, of course, the problem becomes even worse. Premium gas is used but no luck there with alleviating the knock. I'm wondering if a Fuel Injection cleaner might rid excessive buildup within the combustion chamber that might be the cause. Then again, perhaps the problem is simply caused by a need for timing adjustment but this would be too easy! The plugs were changed 2 years ago.

Any advice here on the smoking and pinging would be most welcome.

And one last bugaboo. The engine usually starts on a dime but, depending on the weather (which I've narrowed down to the rain as the prime factor), there are multiple stalls before it catches.

Once again, thanks.
 

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Are your valve cover gaskets leaking?

Have you looked at your plugs? What condition are the plugs in?

will
 

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Discussion Starter #3
I'm not sure if the gaskets are leaking oil and haven't had a chance to take off the camshaft covers to see. There is a great deal of oil leakage, unfortunately, all over the engine but this does not answer the question.

I'm hoping either to comandeer friends who have the appropriate tools to help check it out or gather as much information as possible before going to a mechanic. It's been years since I've driven anything but rental cars, and having never never been under the hood all that much, I'm at a bit of a disadvantage. However, as I share an obsession with these cars, I now have motivation to begin learning.

I'll see if I can pull the plugs and check the gaskets within the next couple of days to check their condition.

Thanks for the direction.

Mike
 

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Smoke in the engine compartment is likely due to leaky cam tower gaskets - the ones between the head and the cam towers, not the covers since those been replaced recently. Oil drips down onto hotter parts of the engine like the cylinder head and exhaust manifold and makes smoke. Pinging is either excessive compression/hot spots i.e. carbon buildup, excessive timing advance, or lean fuel condition. Timing is easiest to check and reset so go there first. If still pings after timing is correct, check under intake manifold to see if the knock sensor wire is plugged in and short the check connector to see if there is a knock sensor code registered. On 85s, the ECU is supposed to retard timing if pinging is detected. A tip I learned recently is that the original plug wires will have the year, 1985 printed on them. Plug wires go bad over time. Check for excessive whitish buildup on the tabs in the distributor cap and feel and listen to the plug wires as you flex them. They should not be brittle and should not make any crackling noises as they are flexed. Your damp starting problem leads me to suspect your plug wires and distributor cap. Check also that the O-ring between the cap and distributor is still there and not hardened. Next go to the fuel system. Lean mixture might be vacuum leak but then it would likely idle a little rough too. In general, the ECU does a pretty good job of keeping fuel mixture in check but thats affected by the O2 sensor. Even if not flashing an O2 code, it might be a good idea to change it at this age and mileage. Its only about $30. Fuel pump could cause lean but also would notice loss of power while climbing as well as pinging if thats the case but at only 112K the pump is probably fine. Carbon buildup is next but its difficult to diagnose without a bore scope and difficult to eradicate without pulling the cylinder head. Its also the least likely cause, trailing probably several laps behind. The tailpipe smoke is most definately worn valve stem seals. Its a tedious job to replace them but well worth it. Can be done with the head in place so if not tackling the job yourself, don't be swayed by astonomical estimates from mechanics who tell you the head has to come off. If I can do it in 8 leisurly hours, then a professional should do in half that and the parts are only $75 or so. If you do this repair, the engine smoke will be fixed in the same step since you'll have to replace the cam tower gaskets anyway after getting to the stem seals. If you have a Haynes manual from the autoparts store, it has instructions for all of this.

Phil D.
 

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Discussion Starter #5
Thanks tremendously for the response and the wealth of info. I'll check everything step by step and look for that manual.

I went through some receipts and found that the fuel pump, strangely, was replaced one year ago. However, perhaps the job was not done correctly as there is loss of power going up the hills that never existed beforehand. Additionally, it looks like the plug wires and distributor cap were replaced at the sametime; I'll check them out anyway.

Thanks again.

By the way, really nice job on the on the 6M-gte upgrade.

Mike
 
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