I was going out to see a fellow 6speed'er so he can see the difference between his flashed/exhaust car and a EPL K16G package car.

I was driving and power was coming on hard and strong as usual (with the cold wheather 2nd just spinning to redline). I did a pull and saw 1.5 bar and then by the time I noticed it went down to 1.3 (where it is tuned to run). I cruzed for about 2-3minutes and hit it again and was waiting for the power to come on line as a gripped my wheel waiting....waiting....waitng .... I looked down to the boost gauge thinking it was going to read 0 as in a massve boost leak, but to my suprise it was 1.3BAR, but feeling like a flashed only car!
The boost is laggy and feels down like 100HP.

I drove the car and noticed that by the time I drove it home the car was loosing boost down to only 0.9BAR .

I hooked up my durametrics and the only fault codes were miss fire in 3 cylinders (most likely just from start up as the car idles very rough until warm).

From my turbo experience, it feels like a boost leak as in a small rip in a coupler that cracked and is now getting bigger. I understand this is a new platefrom that has many little nuances, so before I go spend money on something that might be a common issue (ie maybe a MAF, or limp mode etc.) I thought I might see what input my fellow 6Speed'ers might suggest. I am just sick of paying Porsche tax for simple fixes and know that the Porsche shop I bring it to would be over $300 just to do a boost test and that might not include before AND after turbos. I just got my car running well after many issues and have spent over 19K+ in mods and fixing (7k of the 19K are fixing) things since I purchase this car in May!! I have enjoyed/driven this car about a max of 2 months in total out of the 6 months!

I do not know if this has anything do do with this issue now, but just incase. I was having overboosting issues just before and replaced my N75 valve and the 3 hoses that goes to it and zip tied down everything. That delt with the overboosting, but later that day it started overboosting again. I tightened two zip ties by the N75 valve further and the car was boosting properly again (1.3BAR). The c

I am going to take it to work (at a dealership) and see if I can put it on a hoist to see if all the intercooler hoses underneath looks good and see if the coupler on the throttle body is ripped etc. (hopefully I have the time).

Any help or suggestions would be helpful and much appreciated.


Thanks

Bobby Ali

ba

 

Anyone?

Is there a common part in the 996'T that are known to rip or blow once boost starts going up past 19-20psi?


Any input would be much appreciated.

Thanks

Bobby Ali

ba

 

Bobby, first guess would be a post-compressor boost leak as you said. You can try looking for obvious leaks but you really need to remove the inlet pipes from the turbos, cap the compressor inlets and pressurize -you may find multiple leaks. If you're the DIY type, I would recommend building a set of testers or picking one up from Markski @ 911tuning, buying a set of ramps and an air compressor. A durametric as well. It'll cost a little up front, but after a couple would-be trips to the dealer, you're ahead.

I've seen some cars that will spike boost w/ 1 bar gates in cooler weather -may want to back the gates down a touch after you've got no boost leaks.

 

Yessir, the diverter valve F pipe on left side of motor(between oil filter housing and MAF/inlet pipe). Plenty of other small things that can leak as well, pressure testing as suggested is recommended regardless....

 

Have the durametrics, hope fully off to a good start. Any suggestions with the durametrics?

 

My money is on the boost hose. Common symptom, easy fix.

 

Thanks for your input.

What boost hose?

Thanks

Bobby Ali

ba

 

Assuming nothing is torn, I'm speaking to the F hose. Listen for air loss on a quiet street on acceleration. Its fairly noticable if its ths DV valve hose. Otherwise a simple leak test by any import shop will find it.

 

I just got a report back from the shop that is looking for this power/boost loss and they said that there is no leak!! They said they smoked tested it, then tested it under pressure and tested the FORGED valves to make sure it is not leaking.

I have the following codes:

353-Pressure sensor boost pressure exceeds limit value
440-Pressure sensor boost pressure Porsche fault code
507-Misfire detection (total)
509-Misfire cylinder 6
511-Misfire cylinder 4
513-Misfire cylinder 5
512-Misfire cylinder 3

I just changed my N75 valve last week with all new hoses that attach to it and zipped tied them down. That seamed to of dealt with the over boosting problems, being I couldn't not even get on it with out it over boosting past 1.4.

I thought the misfires had to do with my cold start up, being it idles like a big v8 heavy cammed car, but when it warms up is fine.

The shop told me that they think it is a boost sensor that died or my plugs, but is it just me, but that does not sound right.

How can plugs limit boost.... and most of all after one pull I have feel power, then I get on it again and immediately lose power. I know what blow out feels like....this feels like the boost air is not getting into the motor, but as of their test I am wrong!!!

Again, any input form other members experiences would be a GREAT HELP before I start spending money for now reason. (He wants $700 just labout to do plugs and I feel that they are not even related!).

Thanks

Bobby Ali

ba

 

Tony,

thanks for your input, it is much appreicated!

The over boosting was dealt with the change of the N75 valve.
I am now dealing with the car not making the power it did at the same boost level (1.3BAR) and it wasn't a slow decent in power. It was pulling hard like regular then the next pull, "where did the power go", but yet it showed 1.3 BAR. Since then the boost has been coming down and when I dropped it off at Autowerks this morning it is down to 0.9BAR.

 

I just called Autowerks and they said they replaced the MAP sensor and the car is running smooth. They said the only problem is that it is only boosting up to 1.0bar when it is tuned to 1.3BAR!!

They said it feels strong, it is not pulling any fault codes, not idling rough, but will not go over 1.0BAR!

Again, when this situation happened it still boosted up until 1.3BAR, but down what felt like 100hp and 150ft/tq. It started dropping boost and even at 1.0BAR when it got down there it didn't even feel nowhere as strong as my stock car with 0.9 flash (RENNTECH) tune! So when the shop is telling me that it is running strong on 1.0BAR I would have to be the judge of that, because not because it is even running 1.0BAR doesn't mean it is making the 1.0BAR of power on the set up I have that it is supposed to.....Let alone why it is not running 1.3BAR!

I am running out of ideas and $$.

Thanks

Bobby Ali

ba

 

MAP or MAF sensor?

 

Spark plugs?

 

They said MAP sensor and I clarified it with them and I got them to spell it out for me.

Went there today and the ca is not boosting 1.0 BAR, but the same .8-.9BAR when I brought it to them. Like I suspected the power is down ALOT for even .9 BAR. My stock car with just a RENNTECH tune at .9 felt ALOT stronger.

I asked them to log requested boost verses actual and they did confim that the car is asking for 1.3BAR but it is only getting .9.

I spoke to the owner and told me that he hears some "whirring" of air that I am hearing and he knows there is a leak, but he needs time to find it. I was under the impression that he never looked at the car himself as he said he has been busy, but assured me as soon he has time to put towards it he WILL find it. I feel a little at ease that Courtney the owner didn't look over the car completely, so I feel some hope as he has been wrenching on Porsches for many, many years. So with fingers cross with him looking at it he should find this gremlin!!

I guess on and off for the past four days he had his apprentice's look at it…I don't know???

Again thank you guys for all you suggestions and help!

Thanks

Bobby Ali

ba

 

Boost leak bro it's the throttle body clamp only opens on boost get hands on I dont trust anyone unless I see it. You need to be there

Take your y pipe out