Oil light flickering at idle

Hey guys,

Recently bought my first 1991 MK1 imported GTO! As anticipated I have encountered my first problem. At one stage it was a non-turbo and has had a MK2 twin turbo rebuild transplant. When viewing the car, it seemed as though everything checked out, no warning lights, minor rust, no knocking… it was purring beautifully. It wasn’t until about 40 minutes into my drive home that I noticed the oil light flickering when idling. Purchasing the car for 2.5k, I knew that there would be some problems but as it performed as it should on the test drive, I thought I was getting a steal :joy:

I soon did an oil change (10w40 super mobil semi synthetic) and replaced the filter with a high performance K&N one. The light didn’t come back for a few days but has since been intermittent when idling.

I am going to change the oil pressure switch this Saturday but failing that I know I may be looking at a new oil pump or potentially a bearing has gone.

On my oil pressure gauge at idle, it sits on the lowest notch, but goes up to about halfway when driving which I think is normal.

Any advice or potential solutions would be hugely appreciated!



Welcome to the forum @sampaddypower, would be nice to see some pictures of the car, where in the country are you etc…

Halfway when driving is normal, oil pressure when at idle could be your pump. When you did your oil change did you examine the oil to see if there were any bits or metalics? Could be a malfunctioning switch, these cars are getting on now :grin: Is the oil to the correct level, as I’ve heard/read that even slightly low could cause this problem. Hope its an easy fix for you.

Terry :sunglasses:

Cheers terry,

I’m From London and yeah there was some metal stuck to the magnetic sump plug which is bad sign, but il prepare for the worsed and pray for the best!

Here’s a few snaps!


Hi nice brake clipper custom print paint and also underneath bonnet

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Quick update!

So I changed the pressure switch and the oil light has ceased to flicker! It’s been a few weeks so I’m pretty sure it’s done the job!

But as many of you will know you fix one thing then 2 things break :joy:

Got a rattling noise comming from the engine bay and it’s comming from the area when the belts are so I’ve ingested and and 2 of my pulleys have a bit of play. The tensioner pulley and I think maybe the water pump pulley. Defo not the belt I put WD40 on it and it did nothing.

Also my windows and electric seats stopped working.

Gonna have fun trying to sort them out!



Always a good idea to have full membership… hundreds of how too fix it’s :+1:
Great work.


Yes do get joined, lots of info and stuff, for the membership fee. But check out the crank pulley they can delaminate.
Good luck.

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Aaah, it’s my wedding car :smiling_face_with_three_hearts:


I’ve been meaning to post these for ages!! Did you get the car sorted in the end?


Yeah got it sorted, took it to my local garage for the windows/seat was a wiring connection behind the dash and the pulley tensioner just needed tightening so she’s back on the road :+1:t2: Ace pictures btw mate!


Thanks, that was two years ago yesterday.

Glad you got it sorted relatively easily. Let’s see some pictures of how it looks today…

BTW, let me know if you’re ever thinking of selling it, I miss it. The V8 X5 I replaced it with is cool but just not special enough.



Welcome back to UK Staff !