Overheating problems

[swiftkid 1]

Right, might bit a bit of a long post this one so grab some popcorn.

Basically I have recently converted to obd2 and whilst I was doing it stuck a 6 branch and VT front engine mount (just so you know all the information). At the time I left the lambda sensor from obd1 on for a couple of weeks until I managed to find time to swap it over. I was getting horrific mpg but now it seems to have got better with the new lambda sensor.

My problem is that the engine temp seems to be running at 114-120 degrees, it doesn't run any different, performance is the same (obviously better now its obd2 but other than that no difference). I have ran vagcom and it has brought up no error codes.

I believe out of pure coincidence the aux water pump has died, I have put a feed to it and it doesn't do anything. I have also bridged the radiator sensor and fan stage 1 comes on but no.2 doesn't. I have then bridged the yellow temp sensor and nothing happened there either. Does this mean that the fan controller has packed up?

My biggest concern is why the oil is running so high, it was fine before i did the obd2 conversion, could it just be coincidence? is there anything I should be checking?

Would appreciate any help!

[IanH26 0]

I'd be interested on thoughts on this too as I have also done the OBD2 conversion on my MK3. (OBD1 engine died and got a good deal on an OBD2 + loom).

When running, your aux water pump won't make a difference nor will the fan coming on, as at road speeds the airflow through the rad will cool enough without need for fans.

What is your water temp when driving?

I wonder if there is an issue with the dash readout?

I run mine as a track car so when used its at high revs constantly. Last week at Snetterton in 22deg C ambient I saw 142 degC oil temps! This is with two oil coolers and some oother cooling mods. The water though peaked at around 95-100 before I came in to pits. On the road I saw 70 deg water and 106 deg oil on way home.

I am looking into testing the resistance of the oil temp sender to see if it correlates to other oil temp resistance values as there may be an issue there. I checked with a laser temp gun and the oil system was not registering temps on anywhere that the dash showed it to be.

[swiftkid 1]

Well i've had vagcom running on the water temp and that seems fine, it could be that there is a problem with the oil sender but it was fine before the conversion which suggests its still fine and I have a problem.

Theres no error reports coming up on vagcom, had a carbon canister error but cleared that and its not come back.

Just taken these readings as someone suggested it may be running lean. Problem is I have no idea where to start problem solving if it is! does anyone know if any of these readings are out of the norm

[swiftkid 1]

Right, just thought I would update this incase people are searching for topics. Basically I ran a log on a 15 minute drive, to me it looked like a bunch of numbers but the lambda was doing its job so was going into closed loop which was good!

I was then told that the lambda was adapting a hell of a lot, the figures were fluctuating between -10 to +15 in a very short space of time suggesting the lambda was working very hard to keep it running right.

This suggested that there was a problem with the MAF but as the car still ran fine and the lambda was within the adaption limits no error codes came up. Anyway I replaced the MAF, reset the ECU and *touch wood* it seems to have done the trick. At the moment i'm running a late obd1 MAF but will need to swap that over.

So yea... there you go. The joys of VR6 ownership