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  #31  
Old 04-29-2008, 01:07 PM
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It sure sounds like the oil pressure "problem" is just a faulty gauge. Try a different one, they're relatively cheap used. Also make sure the wiring at the cluster is all intact & well connected.

For the oil burning, what kind of amounts are we talking about here? Is there any evidence (smoking, etc) or just the level dropping in the sump over time? The lift pump would definitely not affect this... nothing you do to the IP will let oil into the fuel supply. The reverse is possible though (fuel can get into the oil).



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  #32  
Old 04-29-2008, 01:12 PM
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The burning oil thought is due solely to the proliferation of smoke coming out my tailpipe that I did not have prior to taking off the lift pump (not IP) and the subsequent and apparent gauge problem.

This car has never smoked so much. It could be from sitting for a week, but somehow I doubt it... I'm going to get a better hookup for a mechanical gauge and then I'm going to start driving her again and see if the smoke clears up or what. That's about all I can think of for now.

Bill
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  #33  
Old 04-29-2008, 01:12 PM
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Quote:
Originally Posted by Icefire View Post
If your dash gauge pegs at 3, with engine off, something is amiss, however your mechanical gauge should level off when the engine is hot at idle, and should be a min of say 15 psi, and if it does keep dropping, then you have a problem.
If the wire is not connected at the sensor, the gauge pegs at 3. I assumed he forgot to connect it, or it's just more proof the gauge is flaky (or, there is a broken wire somewhere).

Also, I thought the mechanical gauge always stayed above 20psi, and was not dropping. It was the electric gauge that was dropping, correct...?

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  #34  
Old 04-29-2008, 01:16 PM
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Quote:
Originally Posted by gsxr View Post
.......... Don't forget to re-attach the wire before turning the car back on, with the wire off, the gauge pegs at 3 before you even start the engine.
It seems that pegging at 3 before starting the engine is normal. With the wire/sender disconnected.

I'm very interested in this thread because I just started experiencing this same problem. Runs fine when cold or revving, always peggs at 3. But idle when hot and it goes down to 1.5 or so. Sometimes 1 bar and even down to zero when hot and at idle. Brand new oil just put in this last weekend.

What is the normal pressure at idle?

Danny
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  #35  
Old 04-29-2008, 01:25 PM
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I just started experiencing this same problem. Runs fine when cold or revving, always peggs at 3. But idle when hot and it goes down to 1.5 or so. Sometimes 1 bar and even down to zero when hot and at idle. Brand new oil just put in this last weekend.

What is the normal pressure at idle?
Danny,

Normally, when hot and idling, the pressure should be around 1.5 bar or so. Maybe a bit less, but I've rarely seen anything as low as 1.2-1.0 bar. However, I believe the official spec in the FSM is something silly like 0.5 bar, which IMO is too low. You may just have an electric gauge problem, though; assuming all W126 chassis have electric oil pressure gauges. (?)

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  #36  
Old 04-29-2008, 01:31 PM
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That's what I thought. Just wanted to make sure.
It was probably my own fault. I used the cheap Coastal oil. I went tothe airport Sunday and saw it at zero when parked at idle.

When I got back I went to Walmart and got some Rotella T and put that in. Actually just put that in this morning. So far looks better but I'll know better when it's run hot later. Both were 15W-40, I'll post what I get during the drive home.

Danny
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  #37  
Old 04-29-2008, 05:14 PM
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Well it started out good. Pegged at 3 as soon as I started it up and stayed there all the way home.
Stopped at a light as soon as I got off the highway and it stayed at 3 the whole time.
Stopped at the next light and it went down to 2.5.
Stopped at the next light and it went down to .5. Went up to 1.5 in neutral.
when I pulled into my parking space it was down at zero again.

Can I pull out the oil filter without getting oil all over? Does the filter housing drain out when the engine is off?

This sucks. I got so much going on right now I don't need this crap!

Danny
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  #38  
Old 04-29-2008, 08:57 PM
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Should be no different from when you change the filter during an oil change. Stick your hand into a plastic bag, roll the bag over the filter as you pull it out of the housing, invert the bag quickly once the filter is out for little to no drip.

Sixto
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