ok, last thread about this junk car

[volks88]

ok so this is what i know. when im in 3rd gear at 3000 rpm and open the throttle quickly, it cuts out almost right away.. when i do the same 3000 rpm experiment in 6th gear, it cuts out about 300 to 500 rpm's later. it feels like its gonna build boost and then falls flat.that seems to tell me its right when boost is coming on. after sputtering the car will see limp mode after 4000 rpm. if i let up for a few seconds the car will return from limp mode. now if i do the same but gently press the throttle i can get it past 4000 rpm's and run it up to 6500 rpm but it must be gently pressed. any quick movement and its toast lol. now these are things i have checked, replaced and ruled out.

• all new coil packs
• changed plugs and tried every gap from .024 to .028
• new MAF sensor
• new CTS
• new intake gaskets
• leak tested
• new o-ring and clips on airbox
• cut hole in air box
• checked injectors
• had CPT rewire MAF plug
• ecu is good
• vacuum tested and read 18hg when warm
• compression tested

now the vacuum is a little low according to EPL telling me it should be 20-21. Al at CPT seemed sure its a hardware issue and is sure if i leave it with him for a few days he can fix it but i live in ky and he's in chicago. if thats what i have to do i will. Al also did a quick log and says the MAF is only reading 200 (g/s) which is obviously low and i think he said the car was NOT seeing full load. help cause i really want to keep this car

[HotSauce]

Is vaccum testing the same as pressure testing? It sounds to me like you're reading a boost gauge. Head over to www.awe-tuning.com and build a pressure tester.

[o3spec]

i call tbb

[Dr. Jekyll]

Sucks man... Something is definitely not right. Definitely sounds like hardware too. Like I've said before, you really need some ECU-x logs, otherwise you're just blindly guessing at the problem. Logs might not show exactly what the issue is, but at least you'll get a better idea of what the car is doing and when.

Get some logs and/or leave it with Al... he knows his stuff.

[exorcet]

you've done so much already, I'd suggest changing the Fuel Filter too. also, how old are your o2 and EGT sensors?

[Aphex350]

I don't think a TBB would have as bad of symptoms as that

[gointoscott]

Sorry to hear about your car troubles.

I see you say you did a leak test, but to me it sounds like you are having boost leak somewhere. If its not pulling full 19-21 psi vacuum and not going to full boost and cutting out if you rev it fast - to me that sounds like boost leak somewhere. our cars rely heavily on a closed system for boost and vacuum.

Another thing I would check that I didnt see in your list is your DV's (unless I missed it in your post). You can test them to see if they are working by taking them out, pushing the piston in then holding your thumb or finger over the vacuum hole and letting off the piston, if it stays in then it works right and holds vacuum, if it goes back to normal position, then its shot. You can do that for both DV's.


Well hope the best for you!!!

[volks88]

i call tbb

samco. checked and rechecked

you've done so much already, I'd suggest changing the Fuel Filter too. also, how old are your o2 and EGT sensors?

o2's and egt's were replaced around 5000 miles ago.

[RolledMySTi]

18hg is off. It should be 20-22hg. You probably have a vacuum leak somewhere. I would pressure test it with soapy water to see where. Make sure you check your spider hose good.

Have you checked your intercooler hoses? Make sure they are on tight and not popping off.

Have you checked your dv's? Are they original or aftermarket?

Good luck. It can be a bitch exercising the demons out of these cars.

[volks88]

18hg is off. It should be 20-22hg. You probably have a vacuum leak somewhere. I would pressure test it with soapy water to see where. Make sure you check your spider hose good.

Have you checked your intercooler hoses? Make sure they are on tight and not popping off.

Have you checked your dv's? Are they original or aftermarket?

Good luck. It can be a bitch exercising the demons out of these cars.

spider hose is new. intercooler hoses seem tight. i'll double check tonight. also will be checking the dv's. i should also note the first time the car started doing it was i was getting onto the on ramp and hammered it in 4th. when i got up near redline the car let out bigtime like i blew a hose off. its been like that ever since.

[Dr. Jekyll]

what kind of DV's do you have?

[volks88]

what kind of DV's do you have?

710n

[RogueStatus]

have you logged it on VAG?

[Dr. Jekyll]

710n

Yea, check those or just replace them if they are old (>30,000 miles). But again, logging would be your best bet. It will take some of the guess work out of it.

[volks88]

so i had one dv that was bad. i popped my stocker in and it seemed better but still hesitated. now from all my experimenting with plug gaps im sure my gaps could be big. i'll let the car cool down and regap

[AudiSportB5S4]

no one recommended this.... but, what type of intercooler do you run? maybe THAT's leaking ?

[volks88]

no one recommended this.... but, what type of intercooler do you run? maybe THAT's leaking ?

i have stock now but a pair of ER's in the box waiting for this problem to be solved

[davism1]

I have ECUx and a pressure tester if you wanna come up this week. I think Im off wednesday all day. Also your end tanks on the stock intercoolers are plastic and could be cracked. PM me if you wanna meet up Wednesday. All I have planned is changing my f-hose and trying to get mine running right as well.

[AudiSportB5S4]

i have stock now but a pair of ER's in the box waiting for this problem to be solved

yeah, as he just said the endtanks sometimes crack... the plastic endtanks are FTL! . anyways, good luck man, if you want drive RIGHT across the state line(s) to CT I'd lend a hand LOL

[volks88]

all i know is there is a serious highh pitched squeal when i hit boost. i have one of my old diverter valves on. would that make a difference having one stock and one a 710n? the reason i ask is since i changed out the bad one, it runs better but still a stutter then limp mode. this shit is getting frustrating

[AMC]

all i know is there is a serious highh pitched squeal when i hit boost. i have one of my old diverter valves on. would that make a difference having one stock and one a 710n? the reason i ask is since i changed out the bad one, it runs better but still a stutter then limp mode. this shit is getting frustrating

put the er's in, get new 710n's (not expensive) and run a boost leak then check it out

[davism1]

The stock DV def wont hold up to 21 lbs of boost so that should be the first thing you need to change. And if you wanna try my baileys and see if that helps its cool by me.

[volks88]

The stock DV def wont hold up to 21 lbs of boost so that should be the first thing you need to change. And if you wanna try my baileys and see if that helps its cool by me.

yeah man i'll probably try and come up wed if thats cool

[S4-ORCE]

did you replace your N75? do some logs..and "high pitch squeal"..could it be a turbo?

[AudiSportB5S4]

lol everything to you is a blown turbo..... the high pitch is obviously signs of air just not doing what it has to do... i didnt know you were running STOCK DV's. that really could be your issue. Even when I went from stock to GIAC chip I took apart my stock DV's, and the rubber inside tears. You need a piston driven DV or a 710n if you dont want to spend too much. I would say thats it, and I think after all that it has to be the issue. mine made the similar sound when broken and would cause it to go limp as well.

[volks88]

lol everything to you is a blown turbo..... the high pitch is obviously signs of air just not doing what it has to do... i didnt know you were running STOCK DV's. that really could be your issue. Even when I went from stock to GIAC chip I took apart my stock DV's, and the rubber inside tears. You need a piston driven DV or a 710n if you dont want to spend too much. I would say thats it, and I think after all that it has to be the issue. mine made the similar sound when broken and would cause it to go limp as well.

i wasnt running stock to begin with. i had the 710n's. when i checked them yesterday i found one was bad so i checked my old stock ones and found one was still good so i figured it'd be good for a pull or two. well the car ran better but still hesitated and thats why i was wondering if having it in there would still cause it to stutter?

[davism1]

i wasnt running stock to begin with. i had the 710n's. when i checked them yesterday i found one was bad so i checked my old stock ones and found one was still good so i figured it'd be good for a pull or two. well the car ran better but still hesitated and thats why i was wondering if having it in there would still cause it to stutter?

PM me or email me at [email protected], Im gonna try to get my car taken care of in the morning but we can meet up whenever you wanna come up.
Let me know
matt

[xx_s4quattro_xx]

i had this problem with my b5 a4 ever since i chipped it and got my timing belt service when i wot the car sputter. like when im at 2000 rpm step on the gas it would lag sputter then just take off like something was holding it back. When i did my k04 upgrade that changed it mike at purems sed my k03 turbo was still in good condition only had a little shaft play but not bad for a car with 130k and original turbo and i had the giac k04 file the point im trying to tell you is it could be your ecu because that fixed my problem.

[The_Jerbel]

18hgin of vacuum is fine. If the stock DV's are in good condition they can hold 21psi no problem.

[volks88]

PM me or email me at [email protected], Im gonna try to get my car taken care of in the morning but we can meet up whenever you wanna come up.
Let me know
matt

sent email

[Turtle]

sorry to hear about your trouble....... But your car looks hot!!!!