OK,

Guys, I need some serious insight in this issue...here is the history and problems:

1) first modded the exhaust...FabSpeed Loud...awesome and Dave reported feeling that his butt dyno was happy and that the car was pulling.

2) I advised Dave that we should upgrade his diverter valves and he agree...got them also through FabSpeed (Excellent service and all the guys are top notch - this is NOT a thread about FS)

3) Changed the valves out - noticed a bit of oil in the hose and at the mouth of the plenum...thought no big deal about it...at the time...

4) Left and Dave calls me 3 days later...threw a code...reset it...it was for running rich...

5) 2 days later calls me up and says...MIke, I am losing power at 5K RPM, I don't get it...I think...lose hose...crap.

6) go over, check all connections and find a hose that is split (the little elbow that is at the bottom of the T hosing from the diverters) replace the hose, check all other connections...were good right?

7) NO...damnit! I go over again, check hoses, take everything apart, re-install (I am getting really good at diverters!) do the ol' Hydraulic Engineer leak check trick and check for leaks...nothing...go for a ride and it here is where I start to have issues and need your help:

- 1st gear is good all the way up to WOT (sometimes sputters too)
-2nd gear is good as I am catching it at 2500-2800 RPM's
-3rd FLAT...sputtering, hesitation and no power from 3K RPM through 5K then it seems to catch...
-OK, so I stay in 3rd let the RPM's come down to 3K, hit it, same thing...flat, hesitation and no power....sucking bad...I had spoken to FS and they thought maybe one of the diverters are bad...OK, next step...

8) I decide that I might be able to figure out which diverter is bad (I don't have a test boost gauge) so I take on of the diverters out and put a stocky back in...I test the diverter (I used my finger to see if it binded in any way or stuck - it is good) re-install everything, test everything, take it out....same issue as before but I notice on my drive that the turbos seem to be very loud and making a spitting noise at WOT....hmmmmm

9) mad now and Dave not happy but eating a steak, I decide to replace everything back to stock...so I take my time...take everything out to include the rubber housing that the diverters use...now I really start to notice that the diverters, the housing all have a small amount of oil residue on them...hmmm...should I be worried? I don't know! again I need your help...and I notice each time I take everything apart the the plenum has a new amount of oil sitting at the mouth on the left side where the diverters are...so I check the right side...no oil...I check the sensor at the split of the plenum...clean! The oil is only at the mouth of the plenum on the left side and on the diverters, and inside the boot.....this has me worried...any insight on oil being in this area would help...

10) OK...so back to the install...everything is stock...check everything....SAME ISSUE...this is not a diverter issue but something else....PLEASE HELP!!! I am at a standstill and don't know what the problem is...the oil has got me wondering....sputtering and loss of power at 3K RPM through 5K RPM, and loud sputtering coming from the turbos at WOT....

I am coming to the best so I hope someone can help me out so I can get Daves car back in order...it is a 2001 996TT and this all started when we started modding his car.

Thanks for looking guys!

Mike

 

no ideas guys? I figured I would be having a tsunami of answers by now!

 

how many miles on the plugs?

 

there is 18K on the ODO...don't know if they have been changed yet....do you think since it is running a little rich it could have fouled them?

 

PLUGS and or loose hose.... but plugs in my opinion for sure. if it sputters at WOT its plugs.,...

 

if I had to make a quick guess by what symptoms you have mentioned, yes.

 

Yeah, I have checked hoses several times so I know it is not that...

if we replace the plugs how do we make sure he doesn't foul those? ECU?

Also, MARKSKI (and no offense oak - thanks for your response) I know you have been on here ages and done many modifications what do you think the oil thing is? is this normal????

Thanks all!

Mike

 

Oil in the diverter valve and at the mouth of the plenum could indicate the turbo's going bad.

 

so the oil cooling the turbo could be bypassing? I am a noob with this car so is there a turbo on each side? I guess he could go hybrid if it is failing or if it is under warranty just get it fixed?

Thanks all, this is helping out a bit...thinking/troubleshooting cap on....

 

what year is it? if it's an 01, and the plugs haven't been changed, it's got the old plugs in it... mine went out at 22k miles. change the plugs, get the ones (6's vs 5's) and you should be good to go.

- chuck

 

cool, looks like we are taking it to the shop next week tuesday to get the plugs changed...we are thinking FR6's for the change and have the tech look at the turbo...the job for me is a bit too much right now...

any insight on getting the car not to run rich? perhaps (and planned) reflash?

Mike

 

Def. spark plugs, happened to me

 

Possibly a vacuum leak somewhere?

Have you done an OBD2 scan?

 

I vote plugs...why don't you get the codes read?

 

I had a similar problem and it turned out to be the plugs also.