100 series oil pressure issue

[Tiny]

for a friend in my club, can anyone shed some light?

[br]I have a 3 year old 100 series turbo diesel. On 2 occassions now I have experienced an unwelcome phenomena. Whilst driving at say 100 kph the oil pressure guage suddenly drops from its normal position of about 3 quarters on the guage to half. Both times this has occurred when we were far far away from any immediate assistance. Strangely the oil pressure increased as we slowed to 85 to 90 kph. Both times this occurred we were close to the 5,000 km oil and oil filter service. The first time this happened, after an oil plus filter change the problem did not re-occur. Then about 35,000 km later on our trip to WA heading south to Meekatharra from Newman it did it again. Again by slowing down the oil pressure came back up - according to the guage. (Normally oil pressure is a function of engine revs - I thought)
So when I took the truck in for service at Toyota Kalgoorlie the guy there said that Toyota have had trouble with the reliability of the oil pressure sender and replaced it under warranty. So far the problem has not happened again.

Has anyone else experienced this?

Oh and the new oil pressure senders have a green earth wire hanging off the end as it seems that Toyota has lost faith in the screw fitting providing an adequate earth.

[red80]

I have a similar problem with my 80 series TD (different engine I know), I think the sender is at fault as it always has a low reading on the gauge but when I unscrewed the sender and fitted a mechanical gauge it was reading up to about 60 psi I would think that your problem was the sender. I am going to fit a permanent mechanical gauge for piece of mind, may be if it is a concern for you too, you could try the same (they are fairly cheap under $30).

[Tiny]

I have a similar problem with my 80 series TD (different engine I know), I think the sender is at fault as it always has a low reading on the gauge but when I unscrewed the sender and fitted a mechanical gauge it was reading up to about 60 psi I would think that your problem was the sender. I am going to fit a permanent mechanical gauge for piece of mind, may be if it is a concern for you too, you could try the same (they are fairly cheap under $30).

thanks, will pass this on, always helps when it aint just you

[80 nsw]

i have had to replace a few of these oil pressure senders on 100 series turbo diesels before. They have all been because of the gauge reading intermittently

[1hzzzz]

Yep had the sender replaced under warranty. a know problem, though not fun when out near Mt Isa and a long way from home.
I have also heard of toyota repacing dash modules to fix problems