problem starting on grand marquis???

i have a 92 grand marquis(4.6)that has developed syptoms that are very steady,the car has close to 160,000 or so miles and whats happening is-every now and then the "check engine light "will flash on a few seconds or so, the
car runs and drives great but if you drive more then an hour or so,and stop at a light for more then a few minutes(car in gear and foot on brake steady idle)the engine will kill,not spudder,or miss ,just flat out kill,the car starts right up no problem and runs fine,but next stop light/sign.give a few minutes and it kills again,if running car within the hour,no problem,if car is in neutral or park motor running,no problem,just in gear with foot on brake after an hour or so after its plenty hot. now another thing is that could help shed light on the problem is-the car eats oil very much,when the car sits a few minutes then your give it gas,there is a cloud of blue smoke from the tail pipe,upon running is it not noticable unless you sit a few minutes then give it gas.there seems to be only this cloud for a few seconds upon accelleration,my guess is that there is probally a piston or two with bad rings(older engine)and that maybe low compression causing the problem??? any ideas or comments??if this is probally the cause,is there any products(high mileage oil,synthetic oil,)or something to help the engine run a little better,i will probally just add oil as i need it,not overhaul it. thanks bob
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You may or may not have two problems,, guess you know that, though..
You didnt mention checking the deposits on the plugs. Did you do that? Some of the old tell-tales still are pertinent.
? Do you get that blue smoke when you start it in the morning? - if you do, that would be indicative of bad valve seals. Otherwise could be broken or worn compression rings. Again, checking the plugs shows a lot. Bad rings also throw smoke when accel after decel.
? Have you serviced the PCV system? Checked for blow-by? Idle engine, remove oil filler cap, put thin paper over filler.
If the problem shows on plug deposits and all cyls about the same, the engine has been run low on oil.
As to additives... I have high personal opinion of Lucas. (from AT Fix product)
And since this engine aint perfect, and has some miles on it... run 20W-50

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Morning smoke - that's valve seals.
But when the light flickers on, it's often TOO late! Unless you're running a good synth. {waiting for the barbs} The oil cools the rings, you see. Once good splash stops, they will over heat on wiper edges.
Agree on IAC, clean it.. go to google, this group.
If you REALLY like that car, and want to keep it otherwise, think about a good used engine.. there are probably plenty of wrecks in the local yards that have been well maintained... though seals may STILL be a problem.
Or just keep it well oiled, try Mobil 1 20w-50 plus Lucas.
And Lucas isnt expensive, considering... neither is Mobil synth.
Let's play 'lucky guess' - you used a Pennzoil or QS oil change place but ran it 6-8,000.
THAT would explain your engine condition. Only use that "biter" oil if you are an every 3,000 on the dot, type.

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