Thread: 300 TDI Disco Oil Light and Power Loss

How many Kms has the engine done? Given the fact that you have done some work on the engine recently, and it seemed to be alright since, I would make sure the oil pressure switch is working alright (it is situated on the oil filter adapter).
The power loss is more difficult to explain. Are your turbo hoses in acceptable nick? You have blanked off the EGR valve, didn't you?
Good luck!
Cheers

Its done 415km. I didnt do the work on the engine. That was my local mechanic. Ive done 5000km since that work with no issues. Will check the switch though thanks.

Sent from my A200 using AULRO mobile app

At that mileage it should have had at least the big end bearings replaced and possibly mains, that would explain the oil light and could explain the loss of power - low oil pressure would prevent lifters from operating correctly (if they are hydraulic) .

Originally Posted by loanrangie

At that mileage it should have had at least the big end bearings replaced and possibly mains, that would explain the oil light and could explain the loss of power - low oil pressure would prevent lifters from operating correctly (if they are hydraulic) .

No fancy hydraulic lifters on a 300tdi - just rollers.

Steve

the oil pressure senders don't last forever in 300tdis, many would have been replaced at lower ks than 415000

Bearings would most likely be due for replacing with that many Km's. I replaced my big end bearings at around 280,000km from memory and they needed it, 300tdi's are hard on bearings from what I have been told. Didnt get around to doing mains at that time though and it is now pushing 400,000kms, but still has good oil pressure.
The oil pressure would've reduced after the long climb as the oil temp heated up as the engine was under load with your foot down and the turbo working pushing egt's up, further heating the oil(I notice this with my 300tdi at high egt temps under load). If your coolant temps increased from an ineffective radiator that too will restrict oil cooling, as the oil cooler runs through the radiator.
What oil are you using? Is your viscous fan OK?
Air filter and intercooler clean? Valve clearances OK? As JoJo stated intercooler hoses OK? They can all have some bearing on power.(No EGR on your 300tdi to worry about)

Yes bearings can be replaced by just dropping the sump, no need to take the head off. With sump off you can check/replace the oil pressure relief valve too. I may be corrected here but I don't know if you can replace main bearing number 5 just with sump off

Thanks for your input guys. Very much appreciated.
Oil is valvoline and all other stuff mentioned is in good order due to the recent engine work.

Just to top it all off my starter motor looks like its on the blink. Its only 18mths old from rimmer bros.
I noticed rimmer bros have a huge range in price for big end bearings. Are the cheaper ones ok to use?
Cheers
Neil

Sent from my A200 using AULRO mobile app

Just thinking outside the square - have you checked your earth straps to the engine/transmission?

Dodgy earth could cause the fuel cutoff solenoid to close giving you the power loss symptom, and also the intermittent starter problem.

Still worthwhile looking at the bearings at those k's though

Steve