oil presssure
11-23-2009, 07:53 PM
#4
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Try the Seafoam in the oil treatment, run good oil like German Castrol, and if it doesn't help, assume you need an oil pump. You could try cleaning the old one including the oil pickup tube/screen first if you want. LS1s are known for this problem, especially the earlier ones. What year is yours?
If the Seafoam treatment helps, do it for your next few oil changes or until it stops helping.
If the Seafoam treatment helps, do it for your next few oil changes or until it stops helping.
11-23-2009, 09:45 PM
#5
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I see about 30-40 hot idle being the norm with a factory pump LS1. Sometimes with age, the relief springs can release pressure early when they warm up. I had this problem on a high mileage 4.3 years back. Cold idle would be 40-50 and hot idle would fall to 5 psi. I replaced the pump and cold idle went to 70 psi and hot idle jumped to 40 psi. Huge difference.
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11-27-2009, 11:48 PM
#8
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More than likely I'm going to say it's not the gauge. My car idles around 60-70 cold and 40-50 warm but it's an LS6 with around 12,xxx on it. My LS1 was just like everyone else was saying. It wouldn't hurt you to put a mechanical gauge on it to see if that's the pressure it's acutally running at but more often than not, it's probably the pump.
11-28-2009, 01:26 AM
#9
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My '98 sees 30psi hot idle, with occasional dips to 25psi under extreme conditions (hot weather, A/C on, lots of WOT, etc.). It sees 40+ by 1500rpm or so. Cold idle is about 45-50psi.
My '02 sees 40psi hot idle, with occasional dips to 35psi under extreme conditions (hot weather, A/C on, lots of WOT, etc.). It sees 50+ by 1500rpm or so. Cold idle is about 55-60psi.
All readings are from the factory gages. Both cars are A4s with factory idle speed settings. Keep in mind the M6 cars idle 150rpm higher than an A4 (factory setting), so their numbers should be just a tad higher.
Both run great, neither burns any oil. The '02 does have piston slap, but lots of '01/'02s have that. I'm not worried about either.
My '02 sees 40psi hot idle, with occasional dips to 35psi under extreme conditions (hot weather, A/C on, lots of WOT, etc.). It sees 50+ by 1500rpm or so. Cold idle is about 55-60psi.
All readings are from the factory gages. Both cars are A4s with factory idle speed settings. Keep in mind the M6 cars idle 150rpm higher than an A4 (factory setting), so their numbers should be just a tad higher.
Both run great, neither burns any oil. The '02 does have piston slap, but lots of '01/'02s have that. I'm not worried about either.
Last edited by RPM WS6; 11-28-2009 at 01:31 AM.
11-28-2009, 09:16 AM
#11
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Before you switch to that. GO pick up German Castrol European Blend thats Made in Germany. Its 0w-30 but oil analysis shows it runs thicker then 5w-30's when warm.
11-28-2009, 12:58 PM
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11-28-2009, 07:42 PM
#14
The first number in any oil is not the weight. Just making sure you know that. I had low pressure in my 98 and switched from a 30 weight to a 40 weight and it helped. This was during the Texas summer though.
Last edited by FatZ28; 11-29-2009 at 03:33 PM.
11-28-2009, 07:44 PM
#15
Some odd readings there man.
I've got an 02' A4 and when it's cold it's at 60psi
Warm it's at 40 idle and high 50's when regular driving.
It only goes above 60 if I push it past 70mph.
It only goes below 40 if I'm idling after some hard driving and even then only by about 2-3psi.
I've got an 02' A4 and when it's cold it's at 60psi
Warm it's at 40 idle and high 50's when regular driving.
It only goes above 60 if I push it past 70mph.
It only goes below 40 if I'm idling after some hard driving and even then only by about 2-3psi.
11-29-2009, 02:29 PM
#16
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In that case, your readings are all at 550rpm (assuming you have stock idle settings).
The numbers I posted above were in park/neutral. I have seen occasional dips to 20-25psi in gear on hot days with the A/C on in my '98 car (in gear, A4). Not a big deal, IMO. But it's only under extremes that I see that. I'm usually in the ~30psi range at idle, in gear, once fully warmed.
All the guys with '01-'02 cars (myself included) will be seeing higher readings, as we have LS6 pumps stock. '98-'00 cars received the LS1 pumps. My '02 car usually reads about 10psi higher than my '98 under the same conditions at the same rpms. I am not concerned about this, as there is a difference to be expected between the two pumps.
FYI. My '99 and '00 LS1s also read about 10psi lower than my '02.
The numbers I posted above were in park/neutral. I have seen occasional dips to 20-25psi in gear on hot days with the A/C on in my '98 car (in gear, A4). Not a big deal, IMO. But it's only under extremes that I see that. I'm usually in the ~30psi range at idle, in gear, once fully warmed.
All the guys with '01-'02 cars (myself included) will be seeing higher readings, as we have LS6 pumps stock. '98-'00 cars received the LS1 pumps. My '02 car usually reads about 10psi higher than my '98 under the same conditions at the same rpms. I am not concerned about this, as there is a difference to be expected between the two pumps.
FYI. My '99 and '00 LS1s also read about 10psi lower than my '02.
12-01-2009, 03:16 PM
#17
oil pressure When cold the pressure is 40-60,when warm 25-40.Would going to a heavier oil help the pressure when warm.What weight oil should I use? I live in Pa. and don't drive the car in the winter.In the 30's is as cold as it gets.Is 25-40 oil pressure ok for a 98 ls1 and I need not worry about it.
