1st Gen R53 Cooper S Most liked posts in thread: Lots of codes after challenging DT BPV install

Yes & No, normally this is just the Map Sensor on the Intake Manifold, so I would just get that one instead of both right away.

(This is of course assuming that you are sure you have no leaks)

 

Hi,
I too have started to get these error codes:
P1242 Secondary Upstream Manifold Air Pressure Sensor Too High in Deceleration
P1238 upstream map sensor input high

I can clear the codes and drive the car 22 miles with no warning lights on, the car drives like a dream. Then the next time I start the car the light pops on and I haven't even driven anywhere.

I have not done any work recently other than a timing chanin tensioner quite a few months ago.

Any help would be appreciated.

 

@PhilA1

What year MINI please?

Mileage?

 

It's a Jan 2006 JCW supercharged 210 BHP which has covered 42,000 miles.

 

any more updates to report?

 

Bypass Valve

Question: Does DT sell a bypass valve with stock spring?

Car: 2006 R52, RMW tuned, Stock with usual bolt-on's, 197 Wheel HP 177 Torque after RMW dyno tuning.

The reason I bought a DT bypass valve is to achieve smooth operation at all throttle settings up to WOT, but after seeing all the negative posted issues have not considered installing it yet.

Theory: We all want maximum boost at WOT, which means we want the bypass valve to close as completely as possible at WOT. That is what DT advertises. My concern is, whether or not, the stiffer spring that DT uses may upset the proportional settings necessary for correct boost at partial throttle at less than WOT.

My theory is we need a valve with a spring tension that is proportionately correct for every throttle setting or power demand up to WOT. In other words, only the necessary boost for the particular need. A stiffer spring would seem to close the valve too much at freeway cruising, as an example, and the ECU is forced to remedy too much boost with extra unneeded gas. I have read this is why the DT valve causes lower mileage. And this is also why we get codes. (I have never had a code)

Has anyone tested for this? The reason I bought the DT valve is for the centering and more accurate closing as well as more precise proportional settings throughout the range. But I am concerned about negative effects from a stiffer spring.

So, my real question is which spring will give the best - PROPORTIONALLY CORRECT results in the DT valve - the stiffer one or the stock one? I did ask RMW about the DT valve and they didn't recommend it unless the stock value is defective. But I am willing to consider something that may be an improvement over stock.

Thanks.