HELP!!! Oil pressure problems

mlmcelligott

I drive a 2004 1.9TDI Toledo (AHF ASV engine code). Yesterday after a long motorway journey and just after I got off the ramp and slowed down the oil pressure warning light started to flash red and a buzzer sounded a few times. Terrified I had killed my car, I pulled over and then all went back to normal, engine sounded fine and nothing seamed to be wrong.

Then after driving I noticed the alarms would sound if I was in the 1500 - 2000 rev band and would stay sounding until I either braked or accelerated out of it.

For the last month a yellow oil warning light would flash a few times after start-up and then wouldn’t appear again so I ignored it until this oil pressure light started flashing. This usually means a faulty oil level sensor.

I’ve bought a new oil pressure switch (038 919 081 K) (there’s only one from what I can see) and a new oil level sensor (1J0 907 660 .

Has this happened to anyone else and what was the issue?

Harcrid

First of all, have you checked your oil level?

C4Kid

a yellow oil warning light would flash a few times after start-up

As far as I know that means oil is running low and it needs to be topped up as it's approaching minimum.

mlmcelligott

yip, oil is at the correct level and engine runs perfectly.

Just spoke to a mechanic there and he suggested to flush the engine to clean it out and remove any chances of blockages. Ill drop it into him in the morning.

cb900ie

I know that some VWs had two oil pressure warning systems, and used two switches. One of the switches closed to bring on the warning light if the oil pressure dropped below 0.6 Bar from memory, while the other switch operated a warning buzzer if the oil pressure dropped below something like 1.5 Bar at an engine speed >2500 rpm. As Seat are in the VW group, it is possible that it has this system.

mlmcelligott

update

Got the car back from the mechanic today. He flushed the engine and said the oil pressure is fine. He also changed the oil pressure switch.

Still got a flashing red oil pressure light and buzzer a few times on the way home.
He did say the flashing yellow oil light at start up was the low oil level sensor in the sump and Ill change that next when it arrives.

Could the low oil level sensor produce the flashing red oil light a buzzer?
How do i test the bonnet switch?

mlmcelligott

Had another look and found a frayed wire on the wiring loom. I cut it and joined it using a connector and its seams to have solved the problem. The yellow flashing light at start up doesnt come on anymore. Havent taken it for a spin yet but hopefully thats the end of it

Bumpstop

Good man, well done.
Thanks for posting the solution,many don't.
It may help someone else.

Leonard Hofstadter

mlmcelligott wrote: »

Had another look and found a frayed wire on the wiring loom. I cut it and joined it using a connector and its seams to have solved the problem. The yellow flashing light at start up doesnt come on anymore. Havent taken it for a spin yet but hopefully thats the end of it

Good to know you've got that sorted, it takes a lot to kill a 1.9 TDI:)!

mlmcelligott

problem came back after 3 weeks of hassle free driving. I put up nearly 1500 miles since the last time the light came on and now it came back on today. I got the low oil level sensor so ill drop the sump and replace it tomorrow. Will clean the oil pick up too.

Last time i took it to the garage the mechanics couldn't find anything wrong but did mention that the crankshaft seal had a small leak. Im guessing that seal is expensive to change since you need to get the timing belt changed to get at it? Could the leak in the seal contribute to low oil pressure? In the two years that ive had it ive had to top up the oil only once so its not a big leak at all.

doctorchopper

No I highly doubt a leaky seal will be the cause of low oil pressure, unless it was absolutely pissing out, but by that time you would be out of oil.