I am curious if those with the larger throttle body 62mm have a flat spot in the RPM range between 2800 to 3200 RPMs. It occurs when you are slowly accelerating in this rpm range and once past, back to normal. It happens in all gears at all speeds and very noticable. In my case it was exactly 3200rpm. I questioned the vendor and was told (that is the nature of the beast) I did a search and was unable to find much. Was my car an exception or is it a standard side effect of the larger TB?
Just curious Thanks

 

It happens on most MCS with a regular TB size.

 

I spoke with Randy Webb several months ago about this. It occurs with all MCS cars but may be more noticable with a larger TB. I think Randy said that it occurres when the bypass valve is not fully closed or open. Notice when you step on it the hesitation goes away.

 

I'm trying to work this out now... I also have a wideband A/F on the car. You'd be SHOCKED at what the A/F ratio goes to. I've seen 18:1 if you are at very, very light throttle. Typically, it goes to 16+ if you do slight increase of the trottle through the flat spot. I have the VGS installed as well....
16 to one if you're holding constant speed on the freeway....
It's not pretty....

Matt

 

I had the problem which I felt was unacceptable. My car never had the flat spot until I installed the Throttle Body. I tried MTH and then had the flat spot and pinging. So I changed to Dinan throttle body, flat spot left but pinging still there. Removed MTH and loaded Dinan S5.(had S3) The car runs better than ever gas milage has increased. I will be confirming the gas milage by the manual method.(because it is better than stock.) I also feel the car has the same power but is smoother in it's delivery of power in all rpm ranges. I plan to dyno this week. I Auto-X'd Sunday tight track hit rev limiter thru the finish every time. No codes thrown. If I lost a couple of horses it is worth it not to have the flat spot.PS. Yes MTH knew I had the S3 on the car when they wrote my upgrade.

 

A bunch of vendors sell these, from a bit under 60mm to 63mm. Please post experiences, all l've found have been questions, two with issues, and one using the Dinan that's happy (and it's posted in this thread, and is the smallest diameter)......

Does ANYONE have a 62 or 63 mm TB without flat spots?
What made it go away?
Do you have ECU mods?

Thanks....

Matt

 

not to change the topic but this flat spot (on mine I would consider it a stumble) got a lot worse after I got a 16% pulley, Milltek catback and Unichip. Mods appear to make it worse, Randy tells me it's the bypass valve...

 

cooldaddy,

We could also build a map for the Unichip to try to sort it better.

I don't remember your specific situation, but there may have been something else too that led me to believe it was a b/p valve.

We didn't have many problems at all with flat spots until recently. Lately, I've had two or three guys call with complaints on this. I remapped one of those cars for the T/B specifically (wiht a Unichip), and he was happy. My guess is there may have been a change made to the factory software that makes this an issue.

Hope that helps!
Randy

 

hey Randy, it's Marcel here . We spoke about the stumble 2 weeks ago and because of my car visiting my Mini dealership this Monday (the "pulley/belt issue" ) I asked them to install the latest software (42. something). But they said there was no update requirement - so my car left unchanged. If an updated map helps (for my standard T/B) I would be interested in sending my Unichip to you for it...

please contact me directly if you have more questions.

Can you confirm that the pulley & belt are on the way? And the set of plugs, and perhaps some stickers?

regards,
Marcel
OKC

 

Stickers too! Sheesh, demanding !

It is all on the way. I'll call you about the reflash - should be no problem.

Randy

 

We didn't have many problems at all with flat spots until recently. Lately, I've had two or three guys call with complaints on this. I remapped one of those cars for the T/B specifically (wiht a Unichip), and he was happy. My guess is there may have been a change made to the factory software that makes this an issue.

Hope that helps!
Randy[/QUOTE]


Randy

This may be a quirk with the V40.? (aka recall flash) The Dinan S5 and the throttle body being smaller corrected mine. I started this thread because I have not heard anything about this before. I think if you check the ones like mine that are having the flat spot, had the recall flash or are late 04s or 05s which came stock with it. V42 may correct it or creat a new problem. The ghost in the machine.

Mike

 

Minirox:

2003 MCS - car did not come with the flat spot. BMW inflicted it on me later and has since blamed it on everything from my CAI to my pulley to my head to a voodoo curse.

I also had the flatspot with the stock throttle body, the JCW injectors, intake and the JCW DME V42. The flat spot first said howdy after I got the car reflashed for the mandatory California emissions. It actually got worse with the JCW DME.

Two weeks ago, I reinstalled the Unichip with Ramp No. 6 and the flat spot and crappy idle have gone the way of the dodo.

 

Hi everyone....

We have looked at the this problem, which seems to have showed it's
ugly head lately. It's definitely a software problem which manifests
it self as a flat spot between 2800-4000rpm at very light throttle tip in
acceleration, never when you go for it (hard acceleration).

We have a newly designed TB geometry, that will increase velocity but
keep the mass of air at a lower rate. I will let everyone know what our findings are next week.

Peter
Team M7
562-608-8123

 

Isn't that just about opposite of what the AGS is supposed to do?
I'm so sure you will post those findings next week unless of course......................

 

the 2800-4000rpm range is exactly what my car is having problems with. At first I thought it was just 3000-3200rpm but after some experimenting 2800-4000rpm is more acurate... it appears to do it with and without the Unichip...

(edit - I have a standard T/B)

 

but I have the emissions recall. MTH didn't help it (but it did bring EGTs down about 75 C and improve general drivability....)

Seems to me, larger TBs need two things...
1)DME Adaptive Reset (to learn the limits of the TB)
2)TB optimized map.

Matt

 

Hey Randy...how's it going with the head serial numbered plate? I'm still waiting:smile:

 

I noticed this the moment my Mini was flashed from V36 to V38 last year

 

[font=&quot]And what exactly is your smart-*** remark suppose to mean.....

Do you rather have us vendors sit on our thumbs, and have guys
like you, figure out the problems from behind your keyboard.

peter
Team M7
562-608-8123
[/font]

 

Actually we would rather have you test your products before bringing them to market instead of having your customers do it for you.

 

Hi Jan....

Such a brilliant recovery from the other thread (I guess this is
your 15th put down of M7 in 22 posts). If you read the post you would find
that this was not a M7 TB specific problem, but for you to grasp that would
send you in to a tailspin of denial.......


peter
Team M7
562-608-8123

 

Where are you in Michigan?

BTW...I also have the large TB and this hesitation problem ONLY appeared AFTER flashing from V36 to V38. I strongly suspect this is the net result of MINI reprogramming the ECU to "soften" the pedal response during initial acceleration, a futile attempt to resolve the "yo yo". Subsequent flash to V41 hasn't solved the problem. I can't believe there's not a way to go back to V36

 

[font=&quot]And what exactly is your smart-*** remark suppose to mean.....

Do you rather have us vendors sit on our thumbs, and have guys
like you, figure out the problems from behind your keyboard.

peter
Team M7
562-608-8123
[/font] [/QUOTE]
No I was not addressing vendors I was addressing you.
Fact is you have no idea who a guy like me is but you seem to know all about sitting on thumbs
Fact is you have a real credibilty issue that seems to get deeper.
May I remind you that I can can screw up things myself without your help.

 

Peter, I appreciate your diversion of the issues at hand.You need to focus on producing quality products instead of making outrageous posts

 

huh? Why are you quoting me and addressing Peter