North American Motoring - HELP - I'm New to Mini

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HELP - I'm New to Mini - P0172 code

Hello All,

I am new to Mini so please bear with me. I purchased an 06 S with several modifications (they are listed below). The check engine light is on and throwing P0172 code. The Long Term Fuel Trim on Bank 1 is at -20% at idle and drops to about -10% at 3,000 RPMs.

The car runs great but I can't get it to pass emissions.

The car did not have a cat on it when I got it. I replaced both O2 sensors and put on new CAT.

Someone recommended replacing both MAP sensors? Is this the next logical step? Any other suggestions?

Thanks,
Scott

The MODS are:

Madness Water-toAir Intercooler
Madness 15% pulley
Madness Intake
Madness Cowl Intake
CHR Head
Madness 380cc Injectors
Schrick Cam
NGK iridium plugs
Nology Wires
MTH Tuner
Madness Header
Milltek exhaust

What cat did you put on the car, and how many miles ago?

Just a note on the P0172 code link. '02-'06 MINIs do not have a mass airflow (MAF) sensor. They have two MAP sensors that work together to determine the proper air/fuel mixture. This is also known as speed density.

You have an aftermarket header and aftermarket exhaust. Look to see if you have an exhaust leak. This can cause false codes with the O2 sensors. Definitely check for vacuum leaks around the engine as well. Get a piece of hose and hold one end to your ear. Listen for a distinct hissing sound.

Another thought that comes to mind is you could possibly have a problem with your high-pressure fuel pump. Testing will require a mechanic's diagnostic.

Thank you for the advice. I am on the hunt. Did find that the rear O2 wiring was touching the heat shield. Fix that now the light is out. Fingers are crossed. I'll report back. Thanks.

You'll have to check your intake for leaks using a smoke tester, most likely cause is the plastic charge pipe from the throttle to the supercharger.

Yes, a smoke tester works too. I forgot about that. I should see about buying one for future use myself.

Quote:

Originally Posted by funR53 (Post 3100629)

i know this is a years old post, but I have the same trim figures on my 04 jcw. Car seems to run great but did used to throw the dsc light on after a spirited acceleration. When I read the ecu I had a p0108 code so cleaned the tmap sensor and that seems to be cured, but still got the quoted symptoms as above. STFT is ok on idle and goes nuts when the LTFT raises to -10, O2 sensors seem to be reading ok, and coolant temp and intake temp seem good too... so I'm left with looking at FPR and injectors (maybe plugs, leads and coil pack)

i also thought i had I had an issue where I was burning oil at a tremendous rate (like a litre to 250 miles) but with no smoke at all. This seems to be improving, strangely, and whilst it's still doing it to a lesser degree, I have noticed a leak again on the rocker box after doing it not 3 months ago... as an outside chance, would a dodgy Pcv valve cause anything like this? I've done the glove test and at idle there's a vacuum as it should be, but not checked off idle

any help gladly received

thanks
Martyn

Bump for same issue -30 trims at idle