Homefried ECU rocks......

[JamesHarrold]

I just pressurise the whole system....TB hose as well.

I have yet to bung the TB hose where it fits to the metal pipe which runs along the head. Is it worth blocking this off when i next do a test?

Cheers

James

[S2central.net]

If you dont bung the TB hose then during the leak test, air squeezes past the piston ring in whatever cylinders have inlet valves open.

Also - yes with high pressure at the intake to the turbo its an unfair test as that hose is never supposed to see boost... You can eaily squeeze air past the oil seals on older turbos (like mine) and hear it bubbling into the sump.

IMO - the best leak test is from the OUTPUT of the turbo to the throttle body. In this setup you can ignore the PCV hoses as you wont be passing air into the inlet manifold, crankcase or MAF hose.

Keep the TBV hooked up during this test as well - it shouldnt leak anything unless vacuum is applied to the control port. If it does you will hear it coming into the MAF hose. That setup should hold pressure indefinitely on a properly airtight leak-free system and avoids any confusion about squeezing past piston rings or oil seals. A tired old TBV might leak a little past if its not a perfect seal, but you can blank that off to verify the main air path from turbo thru IC to TB is airtight.

[Fat Audi 80]

LMAO @ Tom's (Audiman's) comments!

Comedy gold!

[JamesHarrold]

Just taken the car out again and guess what......

Overboost protection....gauge went up to 1.6 bar, got home and pulled 2224.

I really need a definative answer, has this GOT to be a leak somewhere.?
Is there nothing else which would give you overboost protection and 2224?

Sorry for being a PITA guys, but am loosing the will to live.

Cheers

James

[martinjs]

Have you taken off all the boost pipes and physically checked them yourself? if not, thats what i would do.

[JamesHarrold]

Hi Martin....yep, all hoses have been off and checked. Some replaced, but probably not needed to be.

Does anyone know how many hoses there are that can cause Overboost protection if leaking?

James

[HPmuirt]

Is there nothing else which would give you overboost protection and 2224?

I know it has been said before, but the normal reasons for that code are: -

1. Intake air leak after turbocharger
2. Wastegate frequency valve (N75) faulty
3. Vacuum tube from inlet manifold and J220 has leak or is disconnected
4. MAP sensor in J220 is faulty

You have to work through these logically over the weekend: -

1. Check hoses and connectors for leaks. As suggested, concentrate on turbo to the throttle body in isoltation and make sure it holds pressure, not as you suggested leaking over 20mins but rock solid over a long lunch as a minimum.
2. Check your N75 - maybe swap with a loaner unit.
3. Recheck the vacuum lines and gauge/ECU lines

Then post the results.

Cheers n

Si
P.S. I am in Impington, 2 miles north of Cambridge (when I am at home)

[JamesHarrold]

Thanks for the reply Si....but....

Have replaced all vacuum lines, including the one to the ecu...
Fitted spanking new wgfv a couple of weeks ago

So all I am left with is a leak after turbocharger....Will really go to town on the leak testing on my day off (monday)...

Thanks once again for the inspiration Si

Cheers

James

[HPmuirt]

So all I am left with is a leak after turbocharger....Will really go to town on the leak testing on my day off (monday)...

That's what it will be....it is just finding it

Isolate the turbo to the TB section, pressurise to 1 bar and walk away. Come back the next day and.....

...if it is still at 1bar we'll all be monkey's uncles

but....

...if it is not, get the fairy liquid ready....remember your childhood days with innertubes?

Cheers n

Si

[javispa]

Try to check if the internal hoses that control the climate are fine. I am not sure but a friend of mine had boost exeeded problems and I think he told me it was because of that.
I will give him a call to make sure, and let you know.
Cheers!

[JamesHarrold]

Will do exactly as you describe Si....

Let you know on Monday what I find.

Cheers

James

[JamesHarrold]

@javispa

Many thanks

Although I have no Air con....so I guess it wont be the same

Cheers

James

[audiman]

Just as i thought, i was trawling the net on your behalf today. And came across Mr Nugents own website that clearly states the boost levels that should be atained with the WGFV unplugged. I was correct, 3B is 0.6 bar, and ABY is 0.8 bar. I knew i wasnt going mad.

http://www.s2central.net/tuning_02.html

its about half way down.

Paul, your chips work great. Im not slating them in anyway. There are loads on users of the homefries that are really happy and have done 1k's of miles with no problems. you have spent a lot of your own time and money developing them over the years as you pointed out, and im glad that you can provide this sort of tunign for owners at such a good price. Makes a stock S2 that bit more fun

@JAMESHAROLD, if the hose on the cold side of the turbo -> WGFV has a spilt it will cause overboost. BTDT a hundred times.

[Jamo]

My Coupe and Avant both boost to 0.4 with WGFV unpluged what's the story? Different wastegate springs?

[audiman]

not set right!

Fix up!

Virgin wastegates?