My S2 coupe bit of a rebuild and repair thread.

[newsh]

It's probably a boost leak or the MAF pins.

The ECU calculates the amount of fuel needed to go with the air measured by the MAF. If the resultant mixture measured at the O2 sensor is too rich or lean for adaptation then it throws the code and goes to limp mode.

So as you can see, it can be a bad measurement at the MAF or a real loss of air on the pressure side of the turbo.

You will struggle to do a boost test with a hand pump, you need a compressor and a tyre inflator with a gauge. There’s a plumbing end cap that’s the right size to fit the MAF hose. Then you just need a couple of 20mm plugs to isolate the PCV system from the MAF hose. ?

[B5NUT]

I'm a sledgehammer sort of person Dave so will look to replace the lot

Thanks for the advice Kit. I really should have done the boost test when when you sent the kit. I will look to make or get my own as I think as time goes on with the cars hoses they will start to fail. Think that was the first time I've had the car anywhere near the rev limit. Normally keep it to a maximum of 6K. At some point I want the car on the rolling road so I will have to get this sorted. Weather is bloody awful for the next couple of weeks so will look to make my own testing kit. I got a spare pipe that comes from the MAF so should be easy to get something made up.

Think the only thing I need to buy is hand pump with a gauge on it.

[Tractor Dave]

Sudden boost cut can be a real mare to fix. Boost leak test first, then maf pins, temp switch back of head and fuel pump plus others. Mine was the fuel pump slowly failing. Newsh helped me there. Listen carefully to his advice

[K Simmonds]

The give away is 00544 - Maximum Boost Pressure Exceeded is highly indicative of a boost leak, though the fact your can't replicate is a bit weird, normally when a hose comes off or splits then you'll have a leak all the time even at low boost.

The other codes would also be explained by a boost leak as the fueling get thrown out suddenly when it happens.

My thought's are you have a connection somewhere that only leaks under high boost, so when you've use the over-boost of stock ABY mapping it briefly let's go, but as I say that's odd as normally once it's happened it'll do it again at much lower boost levels.

There is a one way valve on the PCV system that Martin mentioned on Fat Audi 80's thread regarding boost leaks, that would be one thing I could think of that could would cause such symptoms.

The S2 has a rev limiter that's fairly soft.

[B5NUT]

So wondering if someone can help with a couple of error codes on the car.

First one is this
00561 - Mixture Adaptation
13-00 - Adaptation Limit (Mul) Not Reached

I believe this could be caused by bad connections on the MAF. I've cleaned the terminals on the MAF with a cotton wool bud and isopropyl alcohol, but struggling to clean the connections on the plug end. So was going to replace them.


Second code is
00544 - Maximum Boost Pressure Exceeded.

This happened a few weeks back when I was on my way back from meeting a forum member, was doing an over take and very soon afterwards it started to cut the boost no matter what gear I was in! I pulled in a little further down restarted the car and it was back to normal power. I've tried to replicate this again but with no luck. I wonder if I got a little to close to the red line. I take it the S2 has a rev limiter

Also, could is this caused by a boost leak? On my other cars when I had an overboost it was normally down to the VVT getting gummed up and sticking. With the S2 not having a VVT what would cause the turbo to create too much boost pressure.

I've cleared the codes and so far they have not come back, but over the last couple of weeks I've done less than 10 miles.

[B5NUT]

Couple of jobs done over the weekend. First was a job caused by a driver who was given their license from kellogg's. They pulled out on me and I had to slam my brakes on! After that the blower motor started making a rattling sound. After spending a while getting the motor out, which I have to say was a complete pain in the backside. I checked the housing and the fan which was cleaned out and the rattle was still there. So stripped the motor out and this came out! No idea what it is or how it got inside the motor housing.
stone.jpg
stone1.jpg

Next up was to service the wiper linkage. To be fair it was in excellent condition, I was expecting the shafts to have started to rust but the only issue I found was the grease had dried out, on everything except the inside the gearbox cover. So a bit of regressing and it's running smoothly again. At least the wiper mechanism was easier to remove than the blower motor!
wiper.jpg

Final job was the aerial. Seal around the base was starting to split, which I figured at some point will let water in.
aerial1.jpg

Got one a genuine VW aerial a while ago, this was the part number.
aerial.jpg

Looks to be a perfect fit, the square fitment locator was the same and the connectors are the same so it was plug and play.
aerial2.jpg

At some point over the next few weeks I want to start machine polishing the car. No idea if it's ever been done since it was resprayed. However it's in real need of a good polish and ceramic coating. Only concern about polishing the car is the roof, it's surprisingly thin and easy flexes so won't be able to put much pressure on to get rid of some of the light scratches.

[B5NUT]

Finally got the 44mm radiator fitted this week. Moving the lower bracket 5mm did the trick. There is no further rubbing of the plastic cowling against the chassis leg.

I know people don't like the Nissens radiators but with them having the brass end tanks modifications like moving the bracket can be made.
2-moun.jpg

The guy that I used modify the radiator also re-soldered all the pipe connectors as some of them did not look the best. I also weld the AC mount back on as one of them had fell off and then welded the other side as I don't think Nissens spot welding was up to the the job.
3-mount.jpg
Also repainted the sides as some of the paint on the sides was flaking off.
4-paint.jpg

The paint on the core looked OK, so just painted the end tanks and sides with epoxy
5-paint.jpg

So far the new radiator is handling the heat better than the 34mm core. I think is down to the larger core and the fact that I used at least 1 and 1/2 liters of extra coolant over the 34mm rad. Also flushed the coolant system again and refilled with fresh coolant. As I'm trying to get rid of the rust in the system. This is the downside of leaving cars to stand for years and not changing the coolant!
rad.jpg
Fitted a replacement upper bracket as I had modified my old bracket by adding an extra 10mm to the length! What I should have done was to fit the rubber mount!
6-bracket.jpg

When I removed the bumper a piece of plastic dropped off the car, and no idea where it came from! Anyway I found out just as I was about to put the bumper back on, that held me up a day as it needed to be fixed.

Bracket on the washer tank had failed
8-bracket.jpg

Drilled 3 holes for some screws on the snapped bracket and heated the end of the screws up so they melted into the plastic on the tank
8-screws.jpg

Then used milliput epoxy putty to strengthen the area.
9-bracket.jpg

It's a bit of a bodge but I will order a replacement tank from tradition when I place the next order. However it's holding the pump just fine until a replacement arrives
10-fixed.jpg

When I had the wings off the car I also sprayed up the door trims that I purchased a while ago. I thought someone had tried to prise off the old ones ,but it turned out that they had just been left of the car when it was resprayed. As all the dirt & crud had not been cleaned up very well the paint had not stuck to the edge of the trims and it was that which was coming away. At some point I will strip them down and repaint them. I still need to sort the rear quarter trim out, but the door trim were by far the worst.

7-trims.jpg

The car is now back on the road again. The wings are 95% OK, there is a slight difference in very bright sunlight from certain angles.
11-car.jpg

[K Simmonds]

Bother, I think I have a couple of spares, though I've missed the post today and can't easily get to a post office on Saturday's, nothing within reasonable cycle range.

I'll have a look though and if one fit's in a little jiffy bag and goes in the village post box I'll send it that way as I have some first class stamps knocking about it and you should have it on Monday.

[B5NUT]

I did wonder why the bottom and side mount had one fitted yet the top was fixed.

Have ordered one won't arrive till Tuesday

[K Simmonds]

They all had them, though there's two slightly different types and I really can't remember which one's got which, pretty sure their interchangeable regardless. I suspect yours got lost whilst someone else was in there and they simply replaced it with a bolt, it's not uncommon to find them missing.

As I mentioned all fixing's for rad's, IC's and oil coolers etc should have some sort of flexible arrangement to prevent stress cracks from vibration.

That's one thing that really irks me with some of the super high spec builds I see, having the (often very expensive) intercooler bolted straight to the crossmember.

Will drop you a PM this evening Lee, had to go and get my elbow looked at this morning, it's okay, I've just been pushing it too hard, durrrr.

[LSG]

My ABY has one fitted, its on a 1994. Maybe diffrent years had them ?

[B5NUT]

Yep, that's correct, just the rad end. Radiators/intercoolers should never be solidly mounted to the chassis, even a flimsy slam panel.

Just had a look at some of the first photo's of the engine bay when I got the car and there was no top rubber mount fitted to my S2.

no-rubber.jpg

They still appear to be available aftermarket 443121273E so will get one on order tomorrow

[Rikki Kitto]

LED hole as Kit says mines got one

[B5NUT]

Don't need it quickly, it's been like that since I got the car so it can wait.

[K Simmonds]

Having worked in the motor trade semi professionally for over 20 years I'm no longer surprised when I find stuff broken that really shouldn't be, people do the most stupid things. Looking at that cowl I expect they lost the original screw and tried to force one much larger in diameter into the hole. I'm not having a dig at all mechanics, I'm far from the best but I've encountered some total Muppets I wouldn't trust with a kettle let alone a car.

The blanking plug is almost certainly for an old alarm LED.

I'll have one of those screws, even got a good idea where. I'm still on dog sitting duty today and besides I've missed the post, but could pop it in an envelope tomorrow for you so you'll have it on Saturday. Or if you can live with no lower cowl until you call around pick it up then.