Normal coolant temps ?

[Jonnybravo]

Whilst idling my S2 runs at about 90 degrees but whilst driving I'm seeing not much over 50 degrees.

Is this a common issue due to the twin rads or more likely to be thermostat related ?

I've not driven the car much yet but first impressions are its awful on fuel, definately running mega rich on boost which I suspect might be connected with the temperature issues ?

[A80Avant]

if everything is stock you should get about 2 small lines above 90C on traffic and about 70C on crusing more or less.However the thermal sensor drops out over the years and might show less temp than the actual.Obviously a lower temp thermostat will also produce those results as well.YOu can check the thermostat by touching the lower of the 2 hoses that you can see from the front of the car just behind the aux rad.When it starts to get hot,check the temp on the car,and you will have an idea of the thermostat.

[Rusty]

Weak thermostat

Richness on boost will not be helped by the low temperatures but more than likely you have a boost leak.

If you've not had the car long then a trip to MRC for a health check could be one of the best things to do, Doug identified a few issues with mine a few years ago and it's been flying ever since.

[dest]

Its not running rich on boost mate, look at the graph from the rolling road!
It is running slightly rich at the top end, which Paul (s2central.net) said is fine and normal when I originally posted them up
Its MPG is average compared to everyone elses on here too lol

[Rusty]

Ah, didn't realise it was your car Dest, your RR ressults were OK. Can you post up the graphs?

Still, sounds like a weak thermostat and at coolant temps. below 80degC it'll run rich as it's in cold start enrichment mode. Get the 'stat changed (not as simple as you might hope ) and it should be better. If the coolant was up to temperature on the RR then it could explain the differences between running well on the rollers and slightly rich on the road.

MPG wise, anything over 20mpg is a bonus in my book and if you get over 25 then you have the patience of a saint!

[dest]

I used to average 22, which was a mix of all types of driving.
I thought the water temp was a down on cold days, and was planning to change it when the cambelt was done next as a matter of course

Graphs:

[Rusty]

Here's mine:-



I had problems at Weston as the boost reference hose that was fitted leaked and caused the overboost protection to cut in, at the RR at Combe I initially cabletied the boost reference hose on and now don't bother so I don't disturb the hoses. The small differences between mine and yours could easily be due to that problem repeating itself, nearly all cars on the day I went were running rich

[Jonnybravo]

i'll definatelay agree with a boost leak, temp 2 sensors on a vauxhall will throw the fueling right out so i expected t.hat might be the issue. Found issue.s with the front diff or wheel bearing today, typically the more miles i do the more issues its showing up, nothing that i'm not capable of sorting though. Its running 9's on full boost so its mega rich, more than likely something has failed since the rolling road day. With det cans on it doesn't like any pulls in 6 th from low revs so i won't be doing any top speed runs till i've checked that ! Who supplied the map for it dest ?

[dest]

Its got a homefry from Paul on here, so the map will be fine.
Search for homefries/homefry and you will find ton of info about it, loads of people have it on here

This is a good place to start:

http://www.s2forum.com/forum/showthread.php?t=352

[4WheelDrifter]

Thermostats can stick open, causing the car to run cool and in a cold start (rich) map. Carefully check the coolant hoses for temperature on warm up, to get an idea of where the hot coolant is flowing. The coolant should be diverted through the heater hoses until the thermostat opens, then you should feel it flow through the bottom hose. Unless you fancy taking the thermostat out and testing it that way.

[Rusty]

Its got a homefry from Paul on here, so the map will be fine.
Search for homefries/homefry and you will find ton of info about it, loads of people have it on here

Including me, hence posting the AFR plot for you Johhnybravo.

You're not running it on 95 are you? That'll kill it especially if the Lambda is old. Had severe issues with mine because of this. Otherwise it's best to get it pressure checked, as I said, MRC are your boys for a full health check, might save you a lot of frustration trying to identify any problems you have.

Get the thermostat sorted and take it from there, check that the temperature sensor on the back of the head is giving the correct values, same with the IAT sensor on top of the inlet manifold.

Welcome to S2 ownership, one day the car is flying, the next it'll decide that it's bored of working properly. Took me 3 years to get mine 99% reliable with full boost without cutting.

The last problem I had was a jubilee clip that had slipped off the Samco TB hose and was leaking ever so slightly. I also minced my DV on track about 2 hours later so it could have been leaking also, worth checking if it's old, the 710Ns seem to last about a year, I went for Forge but that was another set of problems as it leaked! All sorted now though.

Here's the AFR plot from that RR session, the lambda was off scale so the AFRs were <10, different map then but spec was about the same as Dest's car, and boost at max power the same too, result was 273bhp. I got the boost sorted and fitted a new DV and the next session with a homefries was 294bhp.



You can see the torque drop right off with the AFRs, this was a low boost map but it's less than standard for some of the curve!

[dest]

It had a new 710N and N75 within the last year, the exact dates will be in the paperwork.
I NEVER ran it on normal 95 unleaded when I had it

[Jonnybravo]

Thanks for the replies.

I only run it on V Power or if a Shell garage isn't about then SUL.

The wideband is calibrated and its 9's on full chat and looking at the above AFR's I would of expected it to be nicely in the 11's, you can tell when your driving it that its rich, pops through exhaust and rough idle and more obviously the black mist from the tailpipe (although thats only visible by someone following)

I'll sort a stat out for it, I'm more interested in sorting this noise out though now, whenever you drive for anymore than 45mins the noise seems to start, I can't really describe it but I was thinking maybe a wheel bearing but it can sound quite central ie: gearbox, front diff area.

I've not really had the oppurtunity to give it much grief yet, with the bad weather and my unexpected expense at the ring I can't really afford to be out gunning the car around just yet

I have to say though its SO planted in the wet, I've not owned a 4x4 before and as my usual cars are tin cans with big engines and fwd I'm usually very uncomfortable driving in the wet, different story with the S2, superb car

Cheers for the link Dest

[dest]

Ah, I know what the noise is!
I did mention it to you, but Im not surprised you didnt remember everything as it was alot to take in lol
Its basically the same problem everyone suffers from, you need put some new anti squeel stuff on the back of the front pads, its a common issue with the Porsche brakes.
If it disappears when you touch the brake pedal its definitly that. There were on other noises that I knew of!

[Jonnybravo]

I do remember you telling me that actually lol

Its not really that sort of noise but its I'll try touching the brakes the next time it does it, hopefully its a simple fix.

If it was transmission related I would of imagined it would be constant rather than intermitent, we did jack it up and spin one wheel and it made the noise just the once.

I'll let you know how I get on