Oil Pressure drops :(

cobbeh

New Member
May 27, 2009
8
0
0
florida
My car starts from a cold start with 40 lbs of pressure and after about 5-10 minutes of driving will slowly decline until I'm running at about 25-30'ish at highway speeds. At idle the pressure is between 10-20 lbs of pressure.

I brought it to a mechanic, they did a pressure test and confirmed I had a problem. They told me it was the oil pump and quoted about $900 for the fix. It doesn't seem logical to me that a failed oil pump will work until the car heats up.

I can't really afford the $900 to fix the pump just yet. I was hoping I could get some advice as far as anything else I could look into while I try and save some money.
 

Rennat

5psi...? haha
Dec 6, 2005
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Tracy, CA
www.myspace.com
10psi per rpm... if your sitting at 3000RPM on the highway, 30psi is fine...
side note: your cold pressure on a stock oil system shouldnt go above
the supra system is High Volume - Low Pressure 40psi anyways because of the pressure relief in the oil cooler housing right off the block.

some people get like 5psi of oil pressure hot while idleing...

as long as it goes up with engine rpm your fine, but if its only like 10psi on the highway, then you have problems...

http://www.cygnusx1.net/Supra/Library/TSRM/MK3/manual.aspx?Section=LU&P=4
bottom quotes "at idle speed 4.3psi or more"
"at 3k rpm 36 - 71psi"
 

IJ.

Grumpy Old Man
Mar 30, 2005
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I come from a land down under
10psi per 1000 is the maximum not driving at 3000=30 psi....

I'd expect to see at least 40psi @3000 in a healthy engine but having said that the "Shop" is full of shit and trying to take your $900....
 

cobbeh

New Member
May 27, 2009
8
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florida
I had a hunch that was the case. If the oil pump is as hard to get to as I think it is then I don't see how they could know anyway. They barely looked at it before shrugging it off and saying that was the problem. In their eyes I have an "old problematic car" - in my eyes.. it's a classic.

The oil pressure does still rise when I rev the engine. At highway speeds it never goes below 30'ish.

Thanks guys. I was quite worried as this is my primary vehicle.
 

Supracentral

Active Member
Mar 30, 2005
10,542
10
36
cobbeh;1357708 said:
I brought it to a mechanic, they did a pressure test and confirmed I had a problem. They told me it was the oil pump and quoted about $900 for the fix.

#1 - please post the name and address of this shop so other owners can ensure they never do business with a rip off artist.

#2 - Sounds like fairly normal behavior for one of these cars at the age that they are.

Some questions:

When was the last oil change (how long / how many miles ago)?
What oil was used?
What filter?
What's the age of the engine?
What's the overall mechanical condition?
Any ideas on how this car has been maintained over the years?
 

dumbo

Supramania Contributor
Jul 16, 2008
1,911
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Albera, Too Far North
I must say, 900 dollars doesn't seem to illogical from a business point of view. If they were to get a new pump from Toyota thats like what 400 dollars, IIRC.(That what I had to pay up in this place neways). And pulling the engine, or dropping the front end to pull the pan takes time. More than likely the pump isn't the problem but I just wanted to say that. Has anyone had there pump replaced by a shop and if so what did you pay?
 
Last edited:

Supracentral

Active Member
Mar 30, 2005
10,542
10
36
AJ'S 88NA;1358653 said:
Another question to add to Supracentral's list....what weight oil are you using?

That's what the "what oil was used" question was for - I expected a brand and a weight back. ;)
 
Take a new oil filter, punch (not drill) a 1/4" hole in the bottom (punching avoids chips). Solder in a piece of 1/4" copper tubing. Run a fuel hose to a 100 PSI gauge. Put the filter on the engine. That will tell you what the true OP is without hassles, upstream of the filter element. Once hot, pressure drop across the element will be small, especially at idle.

BernieK

cobbeh;1357708 said:
My car starts from a cold start with 40 lbs of pressure and after about 5-10 minutes of driving will slowly decline until I'm running at about 25-30'ish at highway speeds. At idle the pressure is between 10-20 lbs of pressure.

I brought it to a mechanic, they did a pressure test and confirmed I had a problem. They told me it was the oil pump and quoted about $900 for the fix. It doesn't seem logical to me that a failed oil pump will work until the car heats up.

I can't really afford the $900 to fix the pump just yet. I was hoping I could get some advice as far as anything else I could look into while I try and save some money.
 

cobbeh

New Member
May 27, 2009
8
0
0
florida
Supracentral;1357864 said:
#1 - please post the name and address of this shop so other owners can ensure they never do business with a rip off artist.

#2 - Sounds like fairly normal behavior for one of these cars at the age that they are.

Some questions:

When was the last oil change (how long / how many miles ago)?
What oil was used?
What filter?
What's the age of the engine?
What's the overall mechanical condition?
Any ideas on how this car has been maintained over the years?

I guess I'd better just come out and say what you already suspect. I am fairly new to all of this. I've done minor work to my car with the help of more knowledgeable people.

I'm right about due for an oil change. The car has 111,000 miles on mostly original parts. My last oil change was maybe 108,500. Unfortanutely I live in an apartment and don't have my own garage so I used a shop to change my oil last time. I don't know what brand/weight was used. It just recently had the head gasket replaced but it's got a lot of old hoses I've been replacing. The guy that owned it before me kept it very nice in a climate controlled garage in New York.

I didn't have my head on straight when I first got this car. I was always under the "drive it like it was meant to be driven" mentality and didn't take the best care of my car during the first two years. I've since rethought everything and have been trying to take it easy. Trying not to drive it into the ground. I'm trying to do most of the maintenance myself but I live in an apartment and do not own my own garage. It's difficult for me to get anything done in the Florida heat :(.

There are a couple things currently wrong. The engine has a slight hesitation that I'm told is due to an intake leak. I replaced the hoses from the MAF to the turbo/throttle body... but I still can't find it. The turbo hesitates a little as well probably due to the same problem. The clutch is starting to slip and of course the oil pressure problem.

Sorry for the essay but I thought it might help to better understand the idiot you're dealing with :)
 

dumbo

Supramania Contributor
Jul 16, 2008
1,911
0
0
Albera, Too Far North
berniek;1358772 said:
Take a new oil filter, punch (not drill) a 1/4" hole in the bottom (punching avoids chips). Solder in a piece of 1/4" copper tubing. Run a fuel hose to a 100 PSI gauge. Put the filter on the engine. That will tell you what the true OP is without hassles, upstream of the filter element. Once hot, pressure drop across the element will be small, especially at idle.

BernieK

Or just thread a hose/gauge into the block...

OP sounds like she needs some basic TLC, but your oil doesn't seem to be over due at all. If you must bring it to a oil change place to get it done, I recomend bringing your own oil/filter for them.
 

cobbeh

New Member
May 27, 2009
8
0
0
florida
dumbo;1358800 said:
Or just thread a hose/gauge into the block...

OP sounds like she needs some basic TLC, but your oil doesn't seem to be over due at all. If you must bring it to a oil change place to get it done, I recomend bringing your own oil/filter for them.

I will definitely be doing that next time. If I ever bring it back to a shop in this area. I'm finding it harder and harder to trust any of the mechanics I've been to.
 

rayall01

New Member
Oct 10, 2008
901
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Westfield, ma
dumbo;1357929 said:
I must say, 900 dollars doesn't seem to unlogical from a business point of view. If they were to get a new pump from Toyota thats like what 400 dollars, IIRC.(That what I had to pay up in this place neways). And pulling the engine, or dropping the front end to pull the pan takes time. More than likely the pump isn't the problem but I just wanted to say that. Has anyone had there pump replaced by a shop and if so what did you pay?

How about illogical?