Hey guys i was very excited to pick up my car yesterday from the shop. Yes finally turbo. But i ran into a problem..


When I take my car above 4.5 RPM my car kicks into safe mode and after taht shift it wont let me go above 2.5 RPM.. If I turn my car off and on it fixes that and i can drive normally again.. As long as its below 4.5RPM.

When I keep it below 4.5rpm the car sounds great and the turbo pulls nicely. And does NOT go into safe mode as long as it keep it below 4.5 RPM..

Any Ideas what this can be?? My car is an 04 350z track. My mods are below

-Unorthodox pulleys
-Borla dual exhaust. Custom Y pipe to work with Turbonetics..

p.s. My installer did the same kit on his G35 and his works great. Did i get a bad flash?? This is my first turbo car so im very lost right now.. THANKS!

 

Probably NOT the flash. If it was you would be in limp mode as soon as the car started. If you are only hitting 8 PSI of boost my first guess is a boost leak somewhere. Why am I getting the wierdest sense of deja vu right now? Didn't I just talk to you on AIM? Do this:

Take car to installer, turn off car, pressurize system, check for leaks. If this hasn't been done it needs to be. If it has been done you need to verify the vacuum routing. Line from compressor outlet to wastegate lower port. From plenum outlet to BOV upper port. If this is correct attempt to swap MAF.

 

Why didn't your installer come across this problem before giving you the car back? I am no pro but sounds like a MAF problem to me.

 

You are probably hitting the threshold for the MAF and going past the voltage it expects to see, this usually happens around 8-9 psi of boost.

 

Yeah it def sounds like MAF overload to me.

 

westpak, seriously, if that was the case, ALL TN owners would have this issue.

mine reaches 8.5psi, no issues. Taurran is at 9.5psi and no issues.

I think there's a leak around the MAF somewhere, or, maybe they installed it backwards??

 

Nope. I've been up to 10psi on this kit with no issues. My car has never been in limp mode and I beat on it quite regularly boosting to 9 - 9.5psi (with an ebc).

Just like mia said, boost leak or maf problem.

 

What are you basing this info on? At 14.7 ambient, 68 degrees farenheit, on a loaded Dynapck my car can hit 13.7 PSI before the MAF goes over voltage. Tested and confirmed. Where are you getting the 8-9 PSI number from exactly? And what data do you have have to support this? kcobean has boosted as high as 12 PSI continiously without going over voltage in lower temps then mine. I'd say you should have some data to back up your claim.

 

WOW why has everyone changed their view of such an issue, MIAPLAYA you need to keep track of what you answer on other threads

https://my350z.com/forum/forced-induction/159883-problems-with-turbonetics-kit.html

 

He said basically the same thing in the other post, but implied it might be a bad MAF.

 

Um my answer is the same...here are my replies from the thread you linked.

sounds like the SAME EXACT thing I just said...

 

Well depending on conditions not al might reach it at the same boost level.

This is something that was thought a while back, although not from a research lab there is some info here https://my350z.com/forum/forced-induction/62738-bad-news-for-the-big-boosters.html from one of the early boost pioneers on the 350Z

 

simple fact is, he's not maxing out the MAF. Unless his car is a much more incredible air pump than the typical VQ35.

 

Of course the coniditions matter. But the conidition that affects this is MASS AIR FLOW. Not pressure ratio. If the right conditions were met and the MASS AIR FLOW at 8 PSI caused the sensor to go over 4.89 volts (IIRC that is max) then yes it will go into limp mode. At 8 PSI on the 60-1 with ambient pressure of 14.7:1 and ambient temp at 68 degrees farenheit there is not sufficient airflow to cause the sensor to go over voltage. Ambient temp, ambient pressure, and pressure ratio of course will affect this. But so far no one has reported a properly operating system with no leaks causing MAF sensor over voltage at the out of box pressure ratio in temps as low as 30 degrees. His ambient temp is in the 40s according to his AIM message to me and his ambient pressure is not much different then mine. His ambient conditions have been met and exceeded in both extremes by Turbonetics or Turbonetics customers several times over and a over voltage condition was not reached. The thread just linked here while containing good information essentially has ZERO bearing on this thread for several reasons.

(1) That info is over 2 years old and I think we can all agree a lot more is known about this car and ECU now then there was then
(2) The pressure ratio in question in that thread has ZERO bearing on this for the simple fact that there are TWO turbos running at that pressure ratio which have a DRASTICALLY different Mass Air FLow Rate then the 60-1 single turbo does
(3) The ambient conditions were not even stated in that thread (that I saw but I'm not going to read 4 pages of irrelevant info)

 

Well what more is known about the 350Z ECU that would make the info on the thread irrelevant? have you done similar test to come up with different ideas?

 

Several things have been learned may be not by you but by others. For instance how the QA table is altered, how effective the flash is modified for boost, additional injector scaling options, the limits of the MAF under a given pressure ratio ambient pressure and ambient temp, adjustments for ULEV2 ECUs not as easy as Ulev ones, cam phasing, and a myriad of other things. And no I have not run a similar test but rather Turbonetics ran the test. They loaded mine and their G35 on their dyno and ran the boost up to the point where the MAF went into an over volt state. Thats how they determined where the MAF sensor would go over voltage. DO you think they don't test for things like this? The difference in knowledge between early 2004 and now when boosting this car is amazing. Sorry if you fail to see that.

Furthermore what makes that thread irrelevant has already been stated but I'll state it again since you must have missed it.

THE TEST PERFORMED IN THAT THREAD WAS DONE WITH A TWIN TURBO KIT. THIS HAS ZERO BEARING IN RELATION TO A SINGLE KIT AS THE MASS FLOW RATE OF THOSE TWO SYSTEMS AT THE SAME PRESSURE RATIO IS NIGHT AND DAY DIFFERENT. MASS FLOW RATE IS THE MAJOR CONTRIBUTING FACTOR TO THE "MASS AIR FLOW" SENSOR GOING OVER VOLTAGE. SURELY YOU CAN UNDRESTAND THAT 8 PSI FROM A TWIN TURBO SYSTEM IS A DRASTICALLY DIFFERENT MASS FLOW RATE THEN A SINGLE

 

i Can Type Bold Too

 

No boost leaks, 60-1 with typical ambient temp and pressure at 8psi would be impossible to max out. Simple as that. Even with cams and every other breathing mod it would be almost impossible. The only thing that makes sense is a boost leak(higher mass airflow with same differential pressure, in this case 8 psi),a bad reference for the wastegate or a bad maf. TURBO 101.

PS-The Magic number for the MAF limp mode is above 4.74 volts at or below 4500 rpms. That is why all us emanage guys set our voltage clamp at 4.74 below 4500 rpms. Ask Sharif, Phunk, TurboTim, etc.

 

Thank you for clarifying the voltage upper limit. I knew it was high 4 volts but did not recall exactly the voltage number. But as you said its not possible to max the MAF sensor voltage with 8 PSI of pressure added by a 60-1 in a properly operating system. The only answer lies in a boost leak most likely post MAF in which the turbo is being forced to run more pressure and therefore more CFM to maintain that pressure ratio causing the MAF to go over voltage. This has happened as a result of leaking plenums in the past and this case is no different. If the intake piping is secure it could be a leak of the plenum or gasket. Thats why my first suggestion was to pressurize the intake tract and check for leaks.

 

To say it again, for the 50th time.....just so westpak is clear, THE MAF IS NOT BEING MAXED OUT!