oil pressure drop

[glenc]

Any help please. Took the car out for a spin yesterday down to Rye. Went like a dream all the way there about 50 miles. But then started to have problems. When driving oil pressure normal about 50. But when idling dropped straight down to zero and if I had to stop engine wanted to cut out unless I revved it?

[Barkychoc]

What was the temperature doing? Could have been running hot.

Edited for schpellin

Edited by Barkychoc on Monday 10th August 08:20

[glenc]

Temperature normal all the way!!!! Recently had a new water pump fitted.

[Barkychoc]

glenc said:

Temperature normal all the way!!!! Recently had a new water pump fitted.

Has the radiator been bled?
You may have to this a few times to get all the air out.
Make sure the engine isn't short of water, and that the fan belt is tight after the new water pump. Once this has been eliminated (i.e. the most recent set of changes) I'd start to look elsewhere.
Your gauge may have been telling porkies if the engine was low on water.

[glenc]

Thanks for your help. Have bled the radiator. Would the temperature guage not read hot if the car was running hot?

[tvrgit]

glenc said:

Thanks for your help. Have bled the radiator. Would the temperature guage not read hot if the car was running hot?

Not if the water level is low or there's an air bubble so that the temperature sensor can't reach the water!

[jimed]

Am I missing something here? Even if the temp sender wasn't reading correctly because of low coolant would that give no oil pressure at tickover? The oil pressure senders can do strange things when they are on the way out so could be worth checking that out.
Jim

[spivvy]

check here

http://www.pistonheads.co.uk/gassing/topic.asp?h=0...

will tell you how to check pressure switch this is for an S3

[Jed-S]

At this stage I wouldn't assume that the stalling and the oil pressure are related. I did an oil and filter change and then noticed the oil pressure fluctuate. It would register 50psi sometimes but half way through a run it would then drop and at idle there was sometimes no reading. I thought it must have been the different oil but the main problem was the oil pressure sender. Replacing that restored sensible readings. For what it cost (around 15 quid) it is worth doing anyway. I did change the oil from a 10W30 to a 10w40 that I'd used before and that increased the readings slightly when hot but they still were erratic.

Regards the stalling, I'd check for hot running, ie. check the coolant level and check for air locks but in my experience air locks aren't an issue but for some reason it seems that they are always mentioned on here. Having said that, I do keep a close eye on the pressure cap and am on the 2nd one in 3 years. If they don't seal fully then the system will lose coolant and you will have air in the highest parts of the engine like the cylinder heads which is also where the temp sensor is. The swirl pot must be full and a cold level of a couple of inches from the top indicates a leaking pressure cap.

Good luck
Jed

[glenc]

Thanks guys good tips I will check thins out and let you know how I get on.

[The Lukas]

First thing I'd do is check the oil level.

[glenc]

Oil level is ok.