hesitation

[andy123]

ive already eliminated the n75 from my list of possible suspects. you see where it says split intercooler on that e bay ad?jeez....

[CliveH]

Yea, I noticed that Andy - you could always tell the Mrs that this is also part of the problem and put it on your "beloved Xmas list" (see separate thread) - good excuse for fitting an RS4 intercooler...!

[andy123]

I dont think she would buy that. Shes got it in her head that we are going vegas next year so i cant even afford a set of wheels that i want at the moment.Women....
One of my mates had a red ducati 900ss iirc and managed to swap it for a 916, and because it was the same colour his misses didnt notice. I thought that was quite amusing!!

[CliveH]

[eddiecrawford]

andy123, have you done a pressure test? (talking of intercooler leaks...)

[andy123]

wasnt sure how to carry one out. ive done a visual inspection of all the hoses. How would i go about doing a pressure test?its not something daft invoilving a bike pump is it?

[andy123]

sorry to ressurect such an old post but im still having problems and am reapidly running out of things it could be. So far Ive had a new MAf, new N75, and the latest and arguably most annoying thing was yesterday. The cars had a couple of days in my local audi garage where they have tinkered away to no avail until they noted that there was no activity from a lambda probe. I and they both thought this could be messing with the air fuel ratio etc etc. Audi then tried to charge me 4 hours labour and £120 for the part.balls to that i thought, so rung up awesome who did the job for £172. Not the cheapest but they are well equipped and seemed to know what they are doing. Fitted the new lambda sensor and its still doing it. Vagcom was used to reset everything (inc throttle body position, as ive heard this can cause problems) and still its erratic and hesitant. I explained that I wasnt happy about paying Awesome as the work they had done had f*k all effect, and had asked them to diagnose it themselves first before they did anything so they were happy before going ahead, rather then taking the audis garage word on what was wrong with it. When it became apparent the problem had still not sorted, they had no further suggestions apart from one (which i thought sounded like total crap to me) that the ecu is adaptive and make take a while to recognise that the lambda is working again. I thought seeing as the ecu had been reset after the parts were fitted, this would happen instantaneously??It was also suggested that i should leave the battery off for a couple of hours.what a load of balls. unless some one wants to correct me?Other suggestions included shoulder shrugging, head scratching, and smiling as they took £172 off me card.. Im now booked to go back to the audi garage for more aimless tinkering. So far this little episode has probably cost me bout half a grand and im getting rapidly hacked off with it all.rant over.

[andy123]

oh yeah, pressure test and sparkplug condition check is the next course of action from audi.

[eddiecrawford]

do you have vag com?

ecu starts relearning/reading lambdas after a reset ie clear codes or batt out etc

can check lambdas with vagcom. or with a checker, most garages will have them. may be a wiring fault?

[KayGee]

Still sounds like a split pipe to me...... probably a pipe between one of the turbos and n75 valve. Did you get a pressure test done?

[s4woody]

hi andy sorry 2 hear u got probs..my car had severe lack of power and hesitation when i bought it in aug 05 so this is what i changed.. maf,tbb,f hose,both exhaust temp sensors(ecu error code) and i also changed my dv,s 4 forged and all the vaccum hoses 2..i,ve just fitted samco,s and jubilee clips now she,s a flyer..one thing i did notice was the oil recirc pipes that run from the rocker covers,are linked 2 the Ypipe and the f shape hose..now they go brittle cos of heat and crack and that introduces an air leek in2 the boost side of things..bit fiddly 2 change but worth a look..there black plastic and look ribbed it connects 2 the Ypipe with a push clip and goes 2 a 4way block also plastic under the Ypipe then goes 2 the F shape hose under the inlet manifold..only a thought good luck..

[KayGee]

When checking these small pipes, I get a straight through hose joiner (2.5 mm I think) and a spare peice of pipe ( so you can blow down the pipe easily), disconnect each hose and plug in the spare pipe via the hose joiner, give it a blow and listen for leaks. some pipes goto one way valves and sucking may be more appropriate...

Requires little skill but lots of patience.

HTH.

KayGee

[Morpheous]

Just a thought, do you run it on normal unleaded, the knock system can cause this, more so if it has been chipped.
Best way to check for chipping without having to open the ECU is while booting it up the road ask the tech to look at the specified boost in the measured value blocks, if this value is higher than the spec value as listed in the tech info, someone has been in its knickers.
Most centres will do this for turbo cars in warranty to minimise the factory getting shafted for unfair claims.
I know I know we get shafted too.
You can also see the duty cycle of N75 in MVB.

[S4PJH]

I had a problem with my S4 a few months ago. It felt flat when accelerating so I took it to the dealers thinking my MAF had gone again. True enough it had. After fitting a new one it still felt flat even though the dealers said it was fine. So I took it to MRC just before Christmas where they diagnosed it wasn’t getting enough fuel in and thought it was my pump or filter. So we changed the filter first (being the cheapest) and gave it a run. What a difference the car now runs a treat back to 100%. My car has only done 60k & there was loads of crap in the filter. Audi say the filter is a non serviceable item so it never gets changed. Try this it might help, if not take it to MRC they know there stuff.

[andy123]

Just wanted to thank you guys for all your help. Theres a couple of points there that I didnt think about initially and that i will be trying before i send the car back to audi. I did think about the knocking issue before as i had it on my pulsar a while back, and this was causing the car to run like crap, but when we checked the vagcom the other day none of the faults were from knock/detenation sensors.If the cars not getting enough fuel would this show up on the VAGcom? Ive tried running on both optimax and normal fuel to see if there is any difference and there aint. Im going to give my audi garage a couple more hours on it to see if they can find anything else then its going to MRC i think. I did ring them up before xmas with all the best intentions of going down there but due to other commitments its not been possible to get down there as its a good couple of hours away from me.Anyway, thanks again guys and if any of you have diagnosed the correct fault in this thread ill buy you a pint!!cheers!