I have a 2005 R53 and upon startup it revs to 3k then calms down to about 1k, Any ideas as to what this might be ? Sticking throttle body ?

Mods are Header /full Exhaust, MSD Coil/wires/colder Plugs, JCW airbox 0% Alta Lightweight Crank Pulley, 15% Alta V2 SC pulley.

Any help or suggestions would be greatly appreciated.

 

How many miles? Did the issue start after any of the mod installations?

 

It started about a week after I bought it.. All mods were done previously. It has 132k on the clock . It was a little rough when I bought it , now just trying to get everything in working order, this is one the last remaining issues. O2 sensors replaced, Crank sensor replaced, fresh oil change, spark plugs are like new, air filter is clean, just replaced IC boots.. Check for boost or vacuum leaks , and did not find anything.

 

With ECU controlled engine, it will strive to prevent the engine from stalling when things are not so up to snuff. I will bet that there is next to no chance the problem is sticking throttle body. It would be too easy. I have seen all too often people rush out and change the SC BPV or the throttle body.

I recommend you check the basics first, and assess if you have a healthy engine to begin with.

 

An easy thing to do is to remove the air cleaner hose from the throttle body and spay some carb cleaner on the tabs that throttle disc rotate on.

 

I also did notice when letting off the gas the car is slow to decelerate.( slower than the normal lag). It runs great , has good compression across all cylinders, no leaks,doesnt use oil and last oil change oil was clear of debris and metal shavings.

 

I checked the BPV and it seems a little mushy, although I don't have a new one to compare it to .

 

I never touch my Mini's sensitive parts unless its well being warrents. But from what I infer, it is vacuum actuated so mushy would be exactly what I expect because of the rubber diaphragm. It is a very simple device and very easy to determine if it is good or failed. If you have a stock plain Jane one, just disconnect the vacuum line and sux on it. Just don't swallow.

 

I don't plan on sticking random vacuum lines in my mouth.., but I will try spraying the THB butterfly with some cleaner and see if that helps the issue.. I have now developed an exhaust leak at the flex pipe that I have to address as well...

 

Thinking a bad bpv would result in the car not having allot of acceleration as you would never be on boost.

 

Exhaust leak at the flex pipe can skew the upstream O2 sensor's accuracy. But then your problem is with the first moment of (cold) starting the car, which is in open loop so interpret it accordingly and carefully.

 

Prety sure its just a deteriorated Gasket there where it bolts up to the rest of the exhaust.. Should be an easy fix.. Now on the other hand t how to get this JCW airbox out of the way so I can get to the THB.

 

Exhaust Leak fixed.. Nuts right after the high flow cat had loosened and fell off.. Got a new gasket and Nuts and lock washers. anybody know how to get the JCW airbox out so I can clean the thb?