German Car Zone

Hi all,

Me and the miss have been discussing what on earth could replace the MINI when time comes.

One candidate is the 135i and after doing some reading up on it I found only one main concern. The lag issue. It has been determined that this issue originates from a software revision back in spring 2008 that was meant to solve the issue with wastegate noice. The original solution was to keep the wastegate open at low rpm:s and thereby eliminating the noice it produces. This, however, caused severe lag and from what I gather, many people have had problems with lag in their 35i engines ever since.

Word on the street is that the PP upgrade solves the problem, just like almost every other ECU based tuning.

I would like to know if you have any experienced this?

I honestly do not feel any "lag" with this engine.......perhaps I can "feel or imagine" what people are complaining about when below 1500 rpm. On the track, this car rocks......the throttle response is very linear from above 1500 rpm to redline. It honestly feels like a naturally aspirated V8 with its flat torque curve.

Virtually no lag... and below 1500 is not an issue really cause you are not there for more then split seconds.

Compared to a few other turbos I've driven, this engine has NO lag.


In any case, best thing for you is to go and test drive it to see for yourself.

I noticed lag between gear changes on a 135i manual i test drove.

Do you guys know what software revision you have?

People were starting to experiencing lag and worse milage when getting the update to revision 29.2

Can't say I do... I picked up mine in Aug. 2008 and did no upgrades.

Although if a upgrade created worse MPGs (lag issue aside), I cant imagine BMW letting it slide and not do anything about it.

When people here complained, BMW responded that the new software was deliberately made to give a different tune and that this is probably the reason why people are experiencing lag and worse mpg (people have to step on it a bit more to get the same results in terms of performance).

No lag at all. The only issue was with 135 built prior to September 2008, they had a faulty HPFP (High Pressure Fuel Pump). Mine was replaced with the lastet 881 HPFP and its going like a dream, no lag at all...

Thanks Ghusheshe! What do you know of the turbo problems on the 335i? I recall that there were some issues here at altitude and abroad with overheating, limp-mode and even wastegate failure.

Is it ok to link to other forums? There's a 200 page thread on the subject but I don't know if you guys like that link...


Best regards,
south