Boosting issue?
 

I've had my 2005 PPP wagon for just over a year now but never felt it was a punchy as I thought it would be. I came from a 3.2 V6 TT and have had a 320bhp Scooby before, so wasn't sure if my perception was way out.

Anyway, got a OBD2 adaptor and fired up the Dash Command and Torque apps to see what they said on the boost front. Given that they probably aren't as good as a manual boost gauge, I thought they would still give me an indication.

Anyway, peak boost measure on Torque was 9.8 psi and 11.6 on Dash Command. With a PPP'd car (has the piping/backbox and Certificate), wouldn't I expect around 17-18 psi?

Many thanks
Richard.

Std boost is 13/14psi so you currently have sub std boost.
I'd expect as you say over a bar with PPP, probably 1.2 bar ish.
Just depends how accurately your measuring it?

Target boost on the PPP map is 18.72 psi or 1.29 bar.

Thanks guys - is the only real way of accurately measuring boost levels via boost gauge or can the ECU throw out that info accurately?

Romraider logger is pretty good.

an ecu reset might be in order

Thanks for the recommendation Scotty.

Ah, thanks for the suggestion JDM_Stig - I'll have a google on how to reset a newage ECU.

You can do it with romraider ;)

Looks like it's £200+ for the OpenPort cable with adaptors - not sure I'd make any use of it outside of the reset and rare diagnostics - though I'd imagine resale of the cable would be simple enough.

Cheers
Richard

Obd lead from eBay for a fiver does the job you want

Something like this?

http://www.ebay.co.uk/itm/ELM327-USB...item487cc1d1fb

the cheap ones will do the job of logging and resetting of the ECU.
http://www.ebay.co.uk/itm/VAG-GROUP-...item27dad7c735

Excellent - thanks :):thumb:

Or a £10 boost gauge?
Thing is though what are you going to do about it?

before resetting the ECU if you have the ebay/openport lead hooked up with romraider you can check the stored corrections in the ECU - this might give you a clue to any faults or persistent knock that the ECU is picking up.

Come on then, how is a £10 boost gauge going to reset an ecu or assist in logging ?

a £10 boost gauge should be a stage 0 mod along with an upgraded fuel pump - knowing if your vac is low or boost too low/too high can be great when hunting down a problem. The diagnostic lead should then help zone in on what's up.

Thanks - great tip.

Romraider is a very useful too though. It'll log boost etc too, as well as read fault codes, show learned knock correction etc etc. For a £5 lead its well worth it.

Well, got a cable and tried RomRaider (manifold relative pressure - corrected) and it's showing boost between 10 and 11 in general when pushing on and with a peak of 12.6 (min of -11.46). Not tried an ECU reset yet and will check out to see if the restrictor pill is in the right side.

No wonder it feels a bit less pokey than I was expecting!

in romraider logger press the LTV button on the left hand side then hit "save as image" and post the image up :)

Thanks, will do when I get home tonight.

What sort of screen is best, the dashboard one? Also, any other parameters worth displaying/recording?

Many thanks
Richard

Glad you got it working, it's a useful tool :thumb:

i never use the dashboard one, i normally just use romraider for logging to a file then reading the file later with excel so you can draw charts with it. LTV info gives you a decent overview of the car - normally combine with 2 logging runs to make sure all is well.

Loggable items usually include:
Engine Speed
Vehicle Speed
Throttle Angle
Manifold Relative Pressure (direct) PSI
Engine Load
Mass Airflow (g/s)
Manifold Relative Pressure
Boost Error (or Target Boost depending on the ECU type)
Primary Wastegate Duty Cycle
Ignition Total Timing
Feedback Knock Correction
Fine Learning Knock Correction
A/F Sensor #1 (afr) and ideally your wideband reading as well for comparison


Using the above I'd do 2 runs starting around 2500rpm for a WRX or 3500rpm for an STI then take a scroll over the data to see what's what.

Fantastic help - thanks :-)

Will post it up once I've done the runs later.

Cheers
Richard

Hmmm, looks like I'm being a noob. Clicked on LTV and it just says Querying ECU at the bottom of the screen and nothing else changes. I can't have it set-up right, or perhaps the cable isn't good enough? anyway, I'll see what I find on Google.

yeh that's all it normally does, only works when your connected to the car and ignition is on. I normally nab it at the end of a logging session.

Does it just write the info to the log file? Nothing changes on-screen.

once it's queried all the data from the ECU it presents it on screen for you with an option to save as text or save as image.

Ah - with me it just sits saying querying ECU at the bottom and doesn't present the info to the screen. I left it a good 5-10 mins. Does it happen quickly?

Thank for the help.