2G Low vacuum and stuttering

[eclipsalon]

Here's where im at. I have a 96 tsi. prob is unknown, just got it not to long ago and has never really ran perfect. current symptoms: stutters when it gets to 2k, only vacuums at 10, fixed all the leaks with leak detecter, when the car is on u can here the turbo(as in whatever is in the turbo), shaftplay up and down. my guess is the turbo is dead, so.... how bad would it really run if that was the case? or if anyone know what else to check. ive already done full tune up. was the very first thing i did. even bout the whole gasket set from autopart store, and replaced all those.

 

[boosted_ego6985]

First things first if yo can hear stuff in your turbo rattling around when the car is on and just sitting idle then that turbo is DEF dead. Need to either upgrade if ya have the funds or find ya a cheap replacement stock one. You can usually find one on here around $100 or so and most time that includes shipping. I'm not 100% but if it starts stuttering at 2k it's because (going by what you've given) the turbo has crapped out and at 2k you should be starting to build boost but with a shot turbo it isnt spooling as it should and the additional fuel without the air to flow with it it's flooding out your car. My suggestion would be to first replace your worn turbo with a good one and see how that goes for ya. Good luck and keep us updated.

 

[eclipsalon]

been dweling on the turbo thing... i eventually plan on going 450 awhp, plan on using the 20g to get me there, but thats way outta my bugdet so i was thinking about buying a t3/t4 for temporary use. jus so i can keep moding at least till the turbo gives out ### i plan on getting the ebay one, jus because its the cheapest turbo thats "suppose" to be good for the amount of hp i want.

 

[boosted_ego6985]

Don't know too much about the e-bay turbos as I have never used one myself nor have I ever talked to anybody that has. Personally I wouldn't trust one coming off e-bay for the simple fact that there is A LOT of cheap Chinese made pos on there for sale that will end up cracking or doing worse after only maybe 500 to 1k miles and then your out on your money for the turbo and possibly more. Just go with a regular stock T25 for now to get ya going so that you don't have to sink a lot of money into something you may not even be able to use right now. A 20g for your plans should be plenty but of course not without the proper supporting mods along with it so please don't be like some others and think that you can just throw on a new turbo and a boost controller and be able to push 500 hp without anything going wrong. Just remember sometimes the cheapest is not always the best route. If you VALUE your car then don't skimp out on QUALITY over price ESPECIALLY when it comes to your turbo I mean after all that is the MAIN reason we drive these cars am I right? . Most times you can find a quality turbo to be able to make the power you want on here for a great price so when ya have the funds do some shopping on here in the classifieds and see what ya come up with. Also shop the sites online that are reputable for selling turbos as they often have great sales and you could end up scoring a great deal on one. ExtremePSI.com usually has really good deals on REAL quality turbos so maybe give them a try. Good luck either way ya go.

 

[eclipsalon]

replaced the turbo with 14b i got for 50 bucks with j pipe and all the old lines,sweet deal, but the car still does the same, would low compression or oil leaks affect it this bad? jus saying ### valve cover is cracked. also still vacuuming at only 10...

 

[eclipsalon]

really need some help here... car seems to idle fine but when accelerated from 1-2.5 grand it seems to "stutter" as soon as it builds boost it sounds normal. ive tried jus about everything i can think of, would appreciate if anyone had some thoughts jus so i can check off some things, thanks

 

[magik95]

Have you done a compression test? When you say leaks, do you mean boost leaks?

 

[jaycemocapaldi]

If your not making compression very well, could be bent valves. Another thing I would look into is a plugged injector, when you plug up an injector it will act just like this. If you replace you injectors and that fixes your problem, immediatly go and replace your fuel filter to prevent this from happening again.

 

[Lofty]

Spark plugs.
Are they gapped properly?
Are they NGK BPR 6ES?
How are the wires?
Sounds like a boost leak. Are you sure you got all of them?
Hows the compression on the engine, just to be safe.
Are you running premium octane gas?
Are you venting your blow off valve?
It's more than likely spark plugs, a boost leak, or a sensor issue, like a bad MAF or something.

Don't drive it anymore. If you do, stay away from boost.


Do some digging. Get back to us.

 

[smprende10]

unplug your maf. if its a boost leak this will put your car into limp mode basically running rich as hell. see if it still stumbles going slowly up to 2 - 2.5. Also may wanna try cleaning the wire in the maf with some brake clean just spray it down reall good let it dry then put it back on.

 

[321]

2nd that on checking plugs and gap. If you have means of logging, check what the throttle position sensor, cam and crank sensors are doing.

 

[eclipsalon]

guess i can try the plugs cause it does this weird thing some time where it doesnt want to start, turns over and all but wont start just backfires... and as soon as i take out the plugs and clean them up it starts. by the way im not driving the car right now, havent been driving it for awhile now. as soon as i got it i did full tune up... spark plug, wires, timing belt, etc.

 

[Lofty]

Then you're fowling your plugs. They're getting too much fuel.

 

[eclipsalon]

based on what u guys are getting at i must be missing some more leaks beacuse if im flooding the injectors with fuel, and im running rich all the time, then im prob stuck in "limp mode". well be doing test tomorrow then get back at ya'll.

well checked the compressi on it was at 180 on all 4
found a leak at the j pipe, fixed it and now it idles at 1500.
turned it on and reved it up a couple times, jus to see if it still did the same rough acceleration, and it did it all the way to 5g. did sound as bad as before, kinda sounded like a harley but then i figured it jus sounded like that because its open downpipe. then i drove it around the block and it sounded pretty good till u let go of the gas then it drops straight to 1g and sounds like its cam'd out. other then the fact that it peaked out at 20psi and only vaccums at 10psi, i think i got it. almost there maybe. i do have this one thing that looks like it used to be a silonoid. guess i can post a pic of that and hopefully someone can tell me what it is so i can replace it.

 

[eclipsalon]

So ive eliminated all leaks up to 20 psi!! for sure this time. the only ting i cant fix it the rotte body the actual throttle plate but on the spring on the back of the TB, so outside the TB you can hear air escaping.
So now i figure i need a new TB? but then i did put my hand over the intake and it died instantly, which is a good sign (i believe).
So jus wondering what u guys think.

 

[eastace6]

its something else thats keeping you in limp mode, cause im in the same boat right now, iv been told becuase of the bigger turbo my aftermarket exhuast mani and 3inch exhuast its all flowing more and the ecu is freaking out becuase of it and might need to tune the ecu for it.imma keep looking and ill let ya know

 

[mike_tsi]

So does it still studder when accelerating? How much boost are you running? What are you using to tune with? Do you have a boost controller? If your still on stock injectors you may be hitting fuel cut.

 

[yoshi_tony]

well im in the same too since my 6 bolt swap its been frustrating if i step it to full throttle it backfires real bad and no power im running real rich also i fixed the vacumm leaks i changed the turbo, fpr, fuel pump, filters,

i would say change injectors thats what im going to do next keep us updated

 

[casperfast]

check your t-belt timming. i bet you skipped a tooth or two. this can cause low vac, stuttering at 2k and more. pull the top belt cover off and check your marks.

 

[mike_tsi]

well im in the same too since my 6 bolt swap its been frustrating if i step it to full throttle it backfires real bad and no power im running real rich also i fixed the vacumm leaks i changed the turbo, fpr, fuel pump, filters,

i would say change injectors thats what im going to do next keep us updated

How much boost are you running?

 

[yoshi_tony]

12 psi my profile has the mod list up to date

Bolt-on Modifications:
big EVO III 16g, CYCLONE manifold, FP exhaust manifold, 02 housing(bored out) 3" full exhaust(no cat), walbro 255, INJEN intake pipe K&N filter, 1g oil cooler, Unothodox Underdrive Crank Pulley

Engine Management:
95 eprom ecu

Engine Internals:
6 BOLT SWAP, ACL RACE rod bearings, GREDDY timing belt, COMETIC MLS Headgasket, ARP HEADSTUDS, new water pump, all gaskets replaced,

 

[eviltsi]

Cam angle sensor 180 out or timing off....if its backfiring its usually a timing issue.

 

[eclipsalon]

evreything on the car is stock except for the 14b, car on hold for now till i get my 1g tb i just bought in there. No exhaust, open downpipe, no boost controller, stock boost only thing ive done was take the little restrictor out of the WGS, no filter for now, trying to get as much air in the motor as possible since its running rich, as soon as i start driving again ill put it back on no worries. as far as tuning, itll be N/A, still undecided between megasquirt or DSMlink... thats a different story.
How bad would the Crank sensor, Cam sensor, and TPS throw it off?
Also would a pluged EGR be a likely reason? both questions are just out of curiousity dont know if there off or not, although i dont think the EGR works because i blow air in one line and no air comes out the other? unless thats not how its tested?
also only backfires under boost, so i thought it was boost leak due to other threads but only leaking at the TB shaft?

 

[navyvr4]

you're fine running with a dead turbo...but replace it immediately

 

[eclipsalon]

you're fine running with a dead turbo...but replace it immediately

if your saying that the turbo is dead, is it possible even if the shaft doesnt touch the compressor housing? is there other ways to check for a craped out turbo?