2nd Generation Specific (1986-1992) 1986-1992 Discussion including performance modifications and technical support sections.

time for a rebuild?

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Old Dec 3, 2005 | 11:46 AM
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time for a rebuild?

hey, ive been trying to find out why my car is running low oil pressure across the board. (less than 5 psi at idle, 30-40 at 3k rpm) I just changed the sender and the guage is reading exactly the same. I checked the level right after that and noticed small bubbles in the oil and it smells like fuel. I had assumed it was just the guage or the sender, but it seems like its actually an engine problem now. Any suggestions? I had been daily driving the car for a month or so now, and the old owner was driving it with this oil pressure for a while. There is a little smoke that comes out every time i remove the oil fill cap, smells exactly like gasoline. I've got another car to drive for now so I'm not worried if I have to rebuild it, but if theres anything else it could be I'm listening
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Old Dec 3, 2005 | 09:58 PM
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no ideas?
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Old Dec 3, 2005 | 11:21 PM
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check compression
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Old Dec 3, 2005 | 11:27 PM
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appreciate the detailed response, i'm trying to see if anyones had symptoms like this before...
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Old Dec 3, 2005 | 11:40 PM
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Originally Posted by GnubberLang
appreciate the detailed response, i'm trying to see if anyones had symptoms like this before...
May I suggest you change your oil? Perhaps its just old oil.
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Old Dec 3, 2005 | 11:47 PM
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I'm gonna go back to 20w50 tomarow, last time i put in 10w30 to try that out, its been in there for ~700 miles. I've been changing the oil at 1500 because I was worried about the fuel smell in it, never seen the bubbles before though.
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Old Dec 3, 2005 | 11:51 PM
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From: Dandridge, Tennessee
Originally Posted by GnubberLang
I'm gonna go back to 20w50 tomarow, last time i put in 10w30 to try that out, its been in there for ~700 miles. I've been changing the oil at 1500 because I was worried about the fuel smell in it, never seen the bubbles before though.
Well teh fuel smell is normal, but describe the bubbles? You may have a coolant seal that has died and possibly leakign injectors, if yoru car has a hard time starting in the mornings.
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Old Dec 4, 2005 | 12:12 AM
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well i've tried the bubble test (pull the egi fuse, get someone to turn over the car while you check the water for bubbles) and didn't see any, the car starts and runs like normal, a little bit of a bumpy idle. The bubbles were all on the end of the stick, really tiny, i checked it 3 times wondering what the hell they were. the oil is extremely thin and smells exactly like gasoline. I popped the oil filler cap to top it up just incase (it was about 1/4th of a quart off the full mark.) and a little puff of fuel-smelling smoke flew out.
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Old Dec 4, 2005 | 12:18 AM
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Hmm Id change the filter and oil in the next few days, and check your fuel system just in case as well.
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Old Dec 4, 2005 | 07:09 AM
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If you changed the oil pressure sending unit and you are getting the same low oil pressure readings, then it is most likely the o-ring between the front plate and the front cover. This o-ring has a tendency to get brittle and crack. This will cause a majority of the oil to spray back into the pan and never actually be sent through the oil cooler and back to the engine.
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Old Dec 4, 2005 | 09:19 AM
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Originally Posted by GnubberLang
appreciate the detailed response, i'm trying to see if anyones had symptoms like this before...
Not sure he was being a smartass, or trying to be vague by only saying "check compression", but it is really a simple way to answer the question you are asking ("time for a rebuild?"). After all, would you rather replace all the things you think it might be, or just get the compression numbers and leave no doubt?

I personally made that mistake. Had certain symptoms, looked what might cause it aside from low compression, fixed a few things that might be the cause, then finally decided to check compression. Turned out low.

There are bunch of other signs your compression might be getting low, hot start problems, flooding, stalling out at idle, I'm sure there are others.
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Old Dec 4, 2005 | 09:38 AM
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The gas smell is fairly normal. If it is excessive, it can point to several things:
-bad purge valve (check proceedures in the FSM and Haynes manual)
-overly rich mixture (black smoke? excessive fuel consumption? fouled plugs?)
-worn oil o-rings (excessive oil consumptions? blue/grey smoke?)

Your oil pressure problem is likely due to the o-ring that goes between the front cover and front iron. If it blows out, most of the oil being pumped will end up spraying into the front cover...
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Old Dec 4, 2005 | 09:54 AM
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Did anybody mention this yet:

USE A REAL OIL PRESSURE GUAGE, not the stock POS guage in the dash. The oil pressure guage in the car is a joke and replacing the sender doesn't guarantee its accuracy, I speak from experience.

For winter use, use something thicker than a 10w-30. There is no problem using 5W-40 or 10W40 oil. 20w-50 may be a little overkill if it is cold where you live.

It is possibly that you are experiencing excessive fuel dilution with leaky fuel injectors. However, this may not be the case since you didn't mention flooding/hard starting problems.


Oh, please don't knock the responses you get. That is not a good way to get others to help you. Everyone contributes in their own way within the limitations of their knowledge base.
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