Sill not going like it should!

[Glen Chamberlain]

As much as i try, i just can't find the little gremlin that is holding my MY94 ABY back!
I have asked for ideas before on this with lots of replies, but everything tested and replaced doesn’t fix it!

Some times it goes like it should but not very often. Most of the time between 50% - 80% power. It holds back like it's retarding the timing or something just before the over boost protection routine cuts in. It plays up more if i floor it from low down the revs! I get 2413 blinked out which is mixture adjustment and 2224 over boost.

Parts Replaced:
MAF
Lambda
WGCFV

Parts Swapped off a mates motor:
Idle control valve
Air temp sensor

Parts Tested:
Throttle position sensor and idle switch = ok?

Tested for boost and got 1.2 bar?
Tested for boost leaks in boost pipes with 1.2 bar = none found?
Tested for boost leaks in vac pipes with 1.2 bar = none found?

The only head way i found was when i replaced the lambda it was fine but then got gradually back to is old self! (1 week or so) Clean the lambda and what do you know! you gain another week of pleasurable driving? Oh its also **** on fuel? 18mpg as my granny would drive? No smelly cats though!

Miracle cures more than welcome!!!!!!!!!

Thanks in advance guys!

[s2avant]

I'll second that. I'm still having similar problems, full power some days a lot less most of the time. I used to get 2413 before it was home fried and I still occasionally get 2224 especially if I floor it from low down like yours.

I found a huge air leak in my throttle body pipe that cured the problems for about a week. Now it's starting to lose performance again, only this time the leak is fixed

I've changed the lambda probe which did very little, all the vac hoses and will be changing the WGFV this weekend. I'm still wondering about the fuel pump as it's stopped whining now and the slight misfire feeling at about 80mph is a very rare occurence.

I'll post results of the WGFV change at the weekend.

Ben

[Crawford_S2]

Feeling your pain dudes, i have the same problem with my 95ABY coupe. Have changed all the same parts and some more, been like this on and off for over a year. I am going to do the old belt and braces job on the o-ring at the IC and if that doesnt work go over all the pipe work again.

A friend of mine i saw at a wedding recently has put a 3B lump in his UR Quattro with some RS2 goodies for the hell of it. He was having all sorts of overboost problems and eventually cured them when he found a 2 inch split in a 4mm hose round the back of the inlet. Took im years and he reckons just strip and check every hose.

Cant believe this problem is coinsidence but no one seems to have any more definate advise than this.

Still wont get rid though just wish it didnt give me so much grief (car and wife)

[S2central.net]

@Glen - sounds like a minor air leak (or maybe electrical gremlin).

Have you tried/tested/swapped - ???

Throttle bypass valve and the noddy tube that connects it to Inlet
WG diaphragm
WG actuator hose
PCV hoses & valves
ALL the big turbo hoses
Vacuum reservoir
& least but not least the kak O-ring on the intercooler

Check the earth strap for the coil packs is nice and tight also.

Is it running the correct lambda probe and spark plugs or el-cheapo alternatives ?

If you can make it down to Audi International in mid October I'd be happy to give it the once over with pressure testers & VAG-COM etc

Paul

[Glen Chamberlain]

I check all the small hoses and all are very good! holds 16 psi for 5 minutes!!! made some adaptors to check the big main pipes inc ic (not had time to do it yet), but i found the waste gate didn't hold the pressure at all! It makes a hissing sound and looses presssure in 1-2 seconds? I check a mates urs4 AAN and this did not hiss but also lost pressure in 1-2 seconds. I presume it should hold the pressure?

[Doug_RS2]

Are you talking about the wastgate actuator Glen?

I tested mine recently, and it held 20psi for >10minutes with no loss of pressure.

If it is this, be careful changing the diaghram, as my wastgate shaft had been bent and the thread damaged so it wasn't sealing properly.

HTH

[Doug_RS2]

Tested like this:

[s2avant]

Talking of Audi International, I will be throwing down the gauntlet to anyone who can source my problem. There will be a case of beer for the winner.

Ben

[s2avantman]

Glen,

I have also had this problem since May and have changed most parts you mentioned. However, I have noticed in the last week thet I am getting more power and the hesitation seems less (weather cooling down).

Is anyone else noticing this with the same problem?

Karl

[Glen Chamberlain]

Yep! I have noticed this too. Temperature does seem to have a noticeable difference in hesitation and in the likelihood of over boost protection routine occurring! Having said that, i have encountered poor performance on cold days as well?

[bigaudi44]

I know that it sounds obvious but even though you may have certified components here and there from testing, be sure to check the connections on each component. my 3B was stood for two weeks over christmas and got moisture in some of the multi-pin connectors under the bonnet, this caused havoc for a few weeks and gave me a right headache!!

[GADGET]

I feel your pain
I have the very same problem as u on my 95 aby Nothell S2 most of the time its holding back 70% but on the odd occation it turns into a real rocket ship!!! Nice!

It dose run a lot better in the cooler weather for shore!

Been driving me mad for about a year!!!

Need help 2:confused:

[Ski]

I have the same problem too! no.. no i dont.. only kidding.. but it seems a lot of pple have this problem..

i dont know ANYTHING about engines, but i am a computer man, and i look at the theory of things.. what i have noticed, is that a few pple have said something along the lines of "i got this problem when i got the homefry".. could this be the problem?

like i said, i know nothing about engines, but someone did mention that this problem started to arrise when the homefry was installed also the homefry spring does not need adjusting while the mtm chip doesnt? (which i dont understand as they both give same power output?)

anyways.. i just like to feel part of the conversation (although what i just said up there dosnt make sence but did kill my bordem)

[S2central.net]

The occasional hesitation problem on a few of the chipped cars is down to several factors.

Firstly - 98RON fuel is required to avoid knock on the upgraded chips.

Secondly - different engines have different knock limits so *some* cars don't like as much timing advance as others. Mihnea has also got proof of that.

Thirdly - air leaks are the bain of these cars. Little leaks on stock chips become big leaks when boost is increased to 1.4bar. Additonally, any little electrical niggles like dirty connectors will have a much greater impact when the ECU is chipped.

Fourthly - A fuel pressure or supply problem will give the same problem as insufficient fuel will cause knock at max load and high air temps. Also a faulty MAF or lambda sensor will give similar problems - chipped or not.

Fifthly - Load is governed by weight. This hesitation niggle appears on Avants - simply cos the extra load adds to the stresses and liability to knock.

Also - please don't think that the WG spring has anything to do with power output. Just cos MTM sometimes do it on their chips doesn't mean all chips need this. The WG spring can be adjusted to minimise lag and improve spooling time, but it does not increase boost above programmed levels. I generally leave it in stock position as most people don't want the chipped 'look' under the bonnet !

Finally - anyone who has the hesitation niggle with home-fried chips can get a free upgrade to a less aggressive version of chips which reduce the timing a little so that knock is not induced at high load. Obviously the generic chips developed on my car run quite close to the average limit of knock on the ABY engines and that is why *some* cars have this niggle. Its no big deal !

Cheers,

Paul

[Ski]

What is MAF? it looks expensive.. and also .. where the hell can i get this so called "98RON" fuel? is this optimax? (speaking of which whats the difference between optimax and new bp equivalant? )

I could ask quastions all day... i feel sorry for you guys when u meet me at next meeting.. im gonna suck ur brains dry