Hi all

 

It's been a while - honestly, this car has been amazing. 170,000 km on the clock and not much outside general maintenance, until now.

 

I've recently found a small film of oil sitting in my coolant reservoir. Not enough to cause 'major' alarms yet, and not accompanied by any overheating, or performance issues.

I'm not aware of many issues with head gaskets going in these engines, but someone suggested the seals around the oil coolers can have a tendency to go, so I'm wondering if anyone has had experience with that, or if there is something else more common I should be looking for as the cause?

 

And then the big one - I've had the engine check light on for a while. In orange and solid, so no limp mode or change in performance whatsoever (the guy that looked into it even asked if I'd had the ECU tuned as it "goes really good compared to other mk3s he's looked at") 🤣

Anyway, they reckon it's the intake manifold sensor and have quoted me a replacement for the entire manifold, which is going to cost a bomb.

 

What I'm a little confused about is whether it's the manifold, or just the sensor.

I'd assume a faulty manifold would result in reduced, or inconsistent performance, but this drives absolutely fine.

So are these parts one and the same? i.e. do you have to replace the entire assembly, or can the sensor be replace on it's own?

56 minutes ago, Ronnie_Hotdogs said:

Hi all

 

It's been a while - honestly, this car has been amazing. 170,000 km on the clock and not much outside general maintenance, until now.

 

I've recently found a small film of oil sitting in my coolant reservoir. Not enough to cause 'major' alarms yet, and not accompanied by any overheating, or performance issues.

I'm not aware of many issues with head gaskets going in these engines, but someone suggested the seals around the oil coolers can have a tendency to go, so I'm wondering if anyone has had experience with that, or if there is something else more common I should be looking for as the cause?

 

And then the big one - I've had the engine check light on for a while. In orange and solid, so no limp mode or change in performance whatsoever (the guy that looked into it even asked if I'd had the ECU tuned as it "goes really good compared to other mk3s he's looked at") 🤣

Anyway, they reckon it's the intake manifold sensor and have quoted me a replacement for the entire manifold, which is going to cost a bomb.

 

What I'm a little confused about is whether it's the manifold, or just the sensor.

I'd assume a faulty manifold would result in reduced, or inconsistent performance, but this drives absolutely fine.

So are these parts one and the same? i.e. do you have to replace the entire assembly, or can the sensor be replace on it's own?

Golf r, same engine more or less. Oil in coolant at 88k miles. Was the accessory bracket oil cooler assembly gaskets. But having replaced those, and oil in coolant gone, now I'm leaking oil around bracket ... again. Think the bracket may be out of square.

 

The intake manifold is common. Yeah, normally the vw part is the whole  assembly, but you maybe able to research parts and find a ghetto fix.

 

As far as running, it only affects the switch between short and long runners. Difference in running would be very subtle. 

31 minutes ago, TheClient said:

Golf r, same engine more or less. Oil in coolant at 88k miles. Was the accessory bracket oil cooler assembly gaskets. But having replaced those, and oil in coolant gone, now I'm leaking oil around bracket ... again. Think the bracket may be out of square.

 

The intake manifold is common. Yeah, normally the vw part is the whole  assembly, but you maybe able to research parts and find a ghetto fix.

 

As far as running, it only affects the switch between short and long runners. Difference in running would be very subtle. 

Ahh, ok that makes sense.

I don't have any oil leaking elsewhere yet - at least not that I've been able to find.

Looks like the seals themselves are fairly cheap, but the labour is getting on 5-6 hours apparently.

 

I've heard of a few people replacing only the intake sensor themselves, so might look into that. I'm kind of torn as I'm planning to sell it soon, so while I want to get it fixed properly it's a lot of money to not get back through resale if there is an equally as effective solution elsewhere.

 

Cheers - really appreciate the knowledge here.

Can you get it scanned for fault codes?

Oil in your coolant is never good.  It will either be migrating at the coolant package or at the cylinder head.  Time to pressurise your system and find out where the leak is.

7 hours ago, varaderoguy said:

Oil in your coolant is never good.  It will either be migrating at the coolant package or at the cylinder head.  Time to pressurise your system and find out where the leak is.

Or the oil cooler which has a coolant to oil heat exchanger. 

On 20/02/2025 at 06:27, TheClient said:

Or the oil cooler which has a coolant to oil heat exchanger. 

Finally got to the bottom of it - a cracked oil cooler gasket. Now fixed up and running fine, with just a stained coolant reservoir leftover.

Feeling veeeery relieved it was 'just' that and not the head.

On 18/02/2025 at 14:16, ords said:

Can you get it scanned for fault codes?

Yeah, I've since had a couple of places look at it and unfortunately it is a full intake manifold replacement.

Got a couple of prices for genuine and OEM parts, with a decent price difference between them, so I at least have options.