Project: RS2 ABY

[prj]

[Rusty]

Friendly local garage with a decent air compressor setup might be worth a look. Bung them a few £ and you'll have plenty of air to find the leak.

[s2_bo]

Or just take to a petrol station that has a tyre inflator.
Doesnt work on the ones that pump a bit of air then check pressure then pump a bit more..

[Jamo]

Or just take to a petrol station that has a tyre inflator.
Doesnt work on the ones that pump a bit of air then check pressure then pump a bit more..

It works if you select the flat tyre option

[prj]

It works if you select the flat tyre option

Not really, it's a right PITA, and it does not seem to get pressure up well enough.

[Jamo]

Depends which garage done it a few times at the BP station when I had my old coupe, the shell pump was rubbish and didn't work

[prj]

I don't remember what the station was where we tried in the UK, but it did not work.
Never works over here in Estonia either.

[4WheelDrifter]

I think it might work, if you are pumping like a mofo

I can just imagine Andy's OH doing this, while he checks for leaks.

[Ross]

So, boost leak test...

We couldn't get it to hold boost - sounds like it's loosing pressure via the exhaust valves because you can hear air escaping. Seeing up to about 0.6-0.7 bar on the boost gauge max. Checked spark plugs just to be sure. There were some obvious air leaks on the intake which are now solved. Hope was it would make a difference...

We just went out for a spin, need to check the HT leads are on correctly because it now has a nasty intermittent miss on idle... fine >1,000rpm. Boost is peaking at 1.3-1.4bar (target boost is 1.8) and fluttering a little. Andy tells me this is as it was before. It feels like it's holding back, and you can feel it hesitating. AFR's the same... driving off boost about 11.5 getting richer to 9.6 with max boost. Driving round with low throttle or cruising it's sitting on 14.7.

Frustrating, I think we can say the few air leaks are sorted and that has made no difference. Not sure where else to go now. There is a 4442 blink code - which is WGFV - assuming this is still there from running in with it unplugged, but nothing else.

Any ideas... for all I know the holding back boost could be due to overfuelling so be related? Only time I've felt hesitation and a drop in boost (and not to mechanical boost) is with a bad MAF. But it's a brand new one on Andy's car.

[A80Avant]

could it be wrong cam timing?

[s2_bo]

When my RS2 was down from 1.9bar to 1.4bar it was due to a 2" split in the TB>ISV hose so it takes quite a big leak to make a difference of .5bar

Hope you can get it fixed Andy.

[Rusty]

Bummer... Rich running is likely a boost leak, unless you've got the wrong fuel pressure reg in?

[s2_bo]

Ahh, good point Andy.
What bar FPR is the injector map for and whats fitted? Would be great if it was a simple fix.

[Ross]

We pretty thoroughly tested the intake, sorted some leaks, made no difference. Still not holding pressure but it's pressurising the breather system - only way it could be doing this is pressure lost past the piston rings.. I guess after 20-30s of pressure there's going to be some air escaping past the rings, although it was more than I would have expected ?

Also - the AFRs are dropping to 11.5-12.0 if you floor it at low RPMs with no boost which isn't right. There is definitely an issue where by with throttle about >75% it's overfuelling regardless of whether it's making boost or not.

It's an ABY FPR so 4.0bar, and mapped for the same. We would have swapped mine except it was 3.8bar... in hindsight probably would have been worth it as that should have leaned it out and see if that helped

It would be great to see if the hesitation is gone and it makes target boost with the fuelling sorted, but I'm not sure if that sounds viable. It feels great on mechanical boost and AFRs tend to stay above 11, just too slow. It's when boost gets >1bar and AFRS < 11 it really feels horrible.

I'm assured timing is properly set and checked, tested it with my MAF, so in my mind:

Over Fuelling - FPR is not working so pressure is too high? Or injector duty is too high on the MAP.. perhaps it needs to be set for 550s like mine did, rather than 510s?

Not making target boost - WGFV problem (though would have expected it to either spike or make mechanical not somewhere in between) or wastegate not closing properly perhaps? Or, could the ECU be holding back when it AFRs hit 9.6? It does feel like it hits a 'wall' and hesitates, with boost fluctuating at 1.3-1.4bar as soon as they drop below 10.

Could compression be an issue, given we're finding the crank case pressurises as soon as you get >0.5bar in the IM? Perhaps worth doing a compression test?

[prj]

You still have a boost leak.
Block off the breather at the front using a 20mm blank, don't pressurize it with it connected.

Use soap spray and spray down all hoses.

Your car can't hold pressure, runs rich on boost and does not boost target.
Sorry, but it's a boost leak, if you did not find it, search again until you do.
Spray all the injector holes in the inlet manifold as well.

Your theory about exhaust valves etc is not correct.

Good luck.