Jump to content

Welcome to RennTech.org Community, Guest

There are many great features available to you once you register at RennTech.org
You are free to view posts here, but you must log in to reply to existing posts, or to start your own new topic. Like most online communities, there are costs involved to maintain a site like this - so we encourage our members to donate. All donations go to the costs operating and maintaining this site. We prefer that guests take part in our community and we offer a lot in return to those willing to join our corner of the Porsche world. This site is 99 percent member supported (less than 1 percent comes from advertising) - so please consider an annual donation to keep this site running.

Here are some of the features available - once you register at RennTech.org

  • View Classified Ads
  • DIY Tutorials
  • Porsche TSB Listings (limited)
  • VIN Decoder
  • Special Offers
  • OBD II P-Codes
  • Paint Codes
  • Registry
  • Videos System
  • View Reviews
  • and get rid of this welcome message

It takes just a few minutes to register, and it's FREE

Contributing Members also get these additional benefits:
(you become a Contributing Member by donating money to the operation of this site)

  • No ads - advertisements are removed
  • Access the Contributors Only Forum
  • Contributing Members Only Downloads
  • Send attachments with PMs
  • All image/file storage limits are substantially increased for all Contributing Members
  • Option Codes Lookup
  • VIN Option Lookups (limited)

Boost...

skandalis447

By skandalis447
in 996 TT, 996 TT S, 996 GT2

 Share

Recommended Posts

skandalis447 Member

skandalis447

Posted
Posted

Hello there...Until last week my car was completely stock and boost pressure was 0.8 constant...Last week I installed a BMC air filter and I flashed my ECU on a very well known and respective ecu tuner...I am not going to name the tuner since I believe he is about to fix my following problem...The problem is that the max boost pressure I see is 0.8 to 0.9 Not even a spike of 1bar...i was expecting at least 1.0 bar with spikes of 1.1 My worst problem is that the car goes in safety mode with max boost 0.5 and my OBD reader says P1250(over boost pressure)How on earth could this be possible without even reaching 1bar?I mean this limitation should occure at about 1.4 bar...

Link to comment
Share on other sites
fastboydave Member

fastboydave

Posted
Posted

I'm having a few boost issues at the moment also, only achieving 0.6 bar rather than 0.7-0.8 bar.....

Anyway, i would suggest that even though they 'tuned' your ECU to demand more boost, if the 'safety' limit hasnt been altered correctly or got corrupted, then maybe this is why your ECU thinks your are over boosting and going into safe?? Remember, its all parameters and limits in those things and it sounds like one or two aint right?

Link to comment
Share on other sites
Chuck Jones Member

Chuck Jones

Posted
Posted

I dont' know exactly what they did when they flashed your car, but I had the same problem when I replaced the Diverter Valves. I had a leak in the hose to one of the valves and it threw a CEL that indicated overboost and dropped down the the boost level, however in my case it was a vacuum leak caused by faulty hose clamps. I'd say that Fastboy is on the right track....the ECU is generating the wrong message and is creating the signal of an overboost condition even though you aren't in overboost. This is affecting your ultimate boost threshold. So much for a theory from a guy with no MIT degree.

Usually, when you have a problem like this, you go back to the way things were BEFORE you made the change and see if the condition persists. It's too coincidental that you have a flash and now a problem. I hope their support folks are a help to you.

Link to comment
Share on other sites
joyride5 Member

joyride5

Posted
Posted
I dont' know exactly what they did when they flashed your car, but I had the same problem when I replaced the Diverter Valves. I had a leak in the hose to one of the valves and it threw a CEL that indicated overboost and dropped down the the boost level, however in my case it was a vacuum leak caused by faulty hose clamps. I'd say that Fastboy is on the right track....the ECU is generating the wrong message and is creating the signal of an overboost condition even though you aren't in overboost. This is affecting your ultimate boost threshold. So much for a theory from a guy with no MIT degree.

Usually, when you have a problem like this, you go back to the way things were BEFORE you made the change and see if the condition persists. It's too coincidental that you have a flash and now a problem. I hope their support folks are a help to you.

Chuck, when you had the leak by faulty hose clamps, was it near the diverter valves? Did you experience HIGH idle?

Please let me know~

Link to comment
Share on other sites
Chuck Jones Member

Chuck Jones

Posted
Posted (edited)

The leak was at the bottom fitting....the DV has two outlets.....one goes out at a right angle into the "F hose", and the other straight down. I hadn't properly secured the bottom fitting and reused the spring clamp rather than buying a new screw hose clamp. It did not alter the idle....but a searching idle is sometimes indicative of sucking air from somewhere.

Take a can of ether or other flammable spray (carb cleaner) and spray it near the fittings where they attach to the hoses....if the idle picks up, you have found a leak. Don't use too much spray....it is flammable. I use ether that comes in a can and is used for starting engines that are hard to start.

Edited by Chuck Jones
Link to comment
Share on other sites
joyride5 Member

joyride5

Posted
Posted
The leak was at the bottom fitting....the DV has two outlets.....one goes out at a right angle into the "F hose", and the other straight down. I hadn't properly secured the bottom fitting and reused the spring clamp rather than buying a new screw hose clamp. It did not alter the idle....but a searching idle is sometimes indicative of sucking air from somewhere.

Take a can of ether or other flammable spray (carb cleaner) and spray it near the fittings where they attach to the hoses....if the idle picks up, you have found a leak. Don't use too much spray....it is flammable. I use ether that comes in a can and is used for starting engines that are hard to start.

I tried some carb cleaner and no success....

The porsche pressure testing cap was $160... so I just fabricated a pressure tester last night so I'll see if I can locate the leak. Hopefully, I won't need to get a smoke machine and locate the leak quickly..

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share
Go to topic listing
×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.