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nasty oil? whatcha think?

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Old Dec 6, 2012 | 02:42 AM
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Default nasty oil? whatcha think?

So I test drove a 99 t/a today and will probably go back and pick it up tomorrow.
It has a 230,xxx on the original motor and still runs suprisingly well.
Auto, black, charcoal interior if I remember correctly that's in pretty good shape.
The majority of the miles are highway. Drove about 100 a day.

Now the problem,
I pulled the dipstick and there was splotches of light brown sludge.
Wiped it off and checked again. Same thing
Obviously there's coolant coming from somewhere.but from where?
I'm getting the car for $2k so I'm not expecting the motor to last forever.
But would like to drive it for a little while longer after I do a tune up etc.

During the test drive I stomped it. Oil pressure was fine till I slowed down
Then never moved above 18psi
Not matter how far I revved it.
Never made a noise. Car acted like it had fine oil pressure.
Is it possible for the sludge to stop up the oil pressure sending unit?
All help is appreciated!
Thanks
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Old Dec 6, 2012 | 02:43 AM
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Also, I'll add that they run cheap 10w-40 oil in it.
Non synthetic.
And it hasn't been changed in a couple months
Could that cause the sludge?
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Old Dec 6, 2012 | 04:59 AM
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Are you sure it's not just condensation from running short trips only?
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Old Dec 6, 2012 | 05:23 AM
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Originally Posted by Grimes
Are you sure it's not just condensation from running short trips only?
Driven 100 miles a day. Plus you should be able to start and move a car 7 times a foot at a time and never have a moisture issue. Cheap 10w40 wont cause sludge.

If it's worth it to you swap oil and let it ride. Soundsl ike it wont last to me though.
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Old Dec 6, 2012 | 06:24 AM
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id plan an engine as soon as you get it , for that price .
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Old Dec 6, 2012 | 07:36 AM
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My gues would be that the head gasket is going, and leaking coolant into the engine for the age and mileage. As mentioned above, expect it not to last very long, especially after jumping on it. You probably threw a gasket from the high pressure, and tracking it down might be a PITA if you cannot see where it is burning off/leaking.
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Old Dec 6, 2012 | 08:26 AM
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So it could be a head gasket? If so that's no biggy.
I can do that in a few hours.
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Old Dec 6, 2012 | 07:24 PM
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if you get the car ,consider a new oil pump ,O-ring,and a new timing chain.
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Old Dec 6, 2012 | 07:39 PM
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I'd say it's priced too high for a car that'll probably soon need an engine. Bargain it down a bit. The oil issues you stated here would be your argument for a lower price.

Change the oil to a decent synthetic and use a good filter-like a Mobil1 Extended. Then drive it for a week and see what the oil looks like. If it looks good, change it again.

I'd bet the OPSU is shot. Change that (good luck!) and see if the problem with it getting stuck at 18PSI remains.
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Old Dec 6, 2012 | 07:42 PM
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And for beer''s sake, do a transmission filter & fluid job, rear end fluid and flush the coolant out for good old Prestone. Yank the heater hoses, point one at a bucket and run the water hose into the other. New belts, inspect the tensioners.
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Old Dec 6, 2012 | 07:49 PM
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I'd dump 2 bottles of STP engine flush in the engine....let it idle for about 15 minutes. Then drain all the oil. Then fill it with 5 qrts of cheap oil, any kind, any weight. Idle it for 5 minutes. Then drain that out.

Then fill it with Castrol 20w50 and put a new filter on......see what the oil looks like after 10 miles of driving or 20 minutes of idling with a few revs to 2500 and hold it there for 30 seconds each time.

.
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Old Dec 6, 2012 | 10:41 PM
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update: changed the oil with mobil 1 10w-30 and is now holding 45 psi at a hot 1600rpm cruise. when you mash it, damn near hits 80 once it gets up to about 5k. even hot.
which makes me think either hiflow oil pump, or the oil pressure sending unit is trippin out.
ive done a few of em and could have it done in a matter of an hour and a half.
but think ill go on with thinking my 230k mile ls1 is still holding that kind of pressure lol.
i plan on doing a compression check in the next couple days.
if it checks out ok, shes getting a 75 dry shot ;]
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Old Dec 6, 2012 | 10:43 PM
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i ran some 2500 mile royal purple that i pulled out of my last car through it for a few minutes.
ill change the oil again in a couple days.
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