M50 328i will not rev past 6100

[mattnoss]

Hi,
I have a E36 328i that has raced very successful for the last few years but it has developed a problem in that it won’t rev past 6100 anymore (it is a hard cut like a rev limit cut) and also won’t hold a steady throttle over 4500 at standstill.
So far we have checked the fuel pressure ( good pressure and it dosen’t fluctuate when it cuts), changed the primary fuel pump anyway (it runs two OE pumps in the original saddle tank, one for each side). Changed the ECU (both ECU’s have rev limits set to over 7000 rpm), crank, cam, MAF and air intake sensors all with no effect.
As mentioned above it has run without any issues in Sprint and Endurance racing for a number of years and has only recently developed this problem.
Any advise welcome.

[RUSSELLM]

Could it be a timing issue ?

[mattnoss]

Update to this,
Another 328 owner contacted me to say he had the same problem and with the help of a very knowledgeable chap who runs his own remapping company he traced the problem to the Idle Controll Valve on both cars. Not sure why a faulty ICV would have an effect on top end revs but it did.

[4rephill]

A BMW E36 M50 328i? - BMW never made such a car!

The biggest M50 engine in the E36 series was the 2.5 litre.

The 328i was an M52 engine.

[mattnoss]

My mistake, it is a M52. I was never one to get all geeky with model numbers.