I've had my MCa for nearly a year now and I just noticed that the rpms are spiking between 3 and 4 on the tach when I release the gas at 60-50mph. I am not on any hill. I do find that if I gas it a bit more past those speeds, it seems to solve the spiking problem.

Any advice? I've only gone in for 1 service so far and I am not due for another 10K or so. Now I'm questioning that reading as well. Is this a problem worth involving the dealer?



thanks! Any comments would be really appreciated.

 

So you're doing 50-60mph and less than 3k RPMs, you let off the gas and the tach needle spikes up between 3 and 4k RPMs? Your engine isn't reving in conjunction with that is it? Either way it's time to call your service center, don't wait for the next service period.

 

What do you mean by spiking?

It jumps up there by itself or it doesn't go above that rpm during normal acceleration?

Your engine won't go above 4k rpm unless you press your pedal past the click you feel near the floor.

 

I didn't wait and took it in and they said all was good. However, I still feel that it's driving weird.

Acceleration is fine. It's deceleration that the rpms spike to between 3 and 4. And it hums/revs really loud too. I don't know much about cars, but aren't the rpms supposed to go down once you release the gas? And what's strange is that I can be cruising at 70mph and under 3rpm then release the gas and when it hits 60mph the rpms spike (go by themselves without me pushing the gas) to btw 3 and 4. Is this normal? They said everything was okay at the dealers, but I just wanna make sure. I'm still under warranty and if it still continues, I'll take it to another dealer to check it out. I did not appreciate the service at this last one.

Thanks for the help!

Keep posting =)!

 

Does it seem like the car downshifts when the RPM spikes?

 

Hi Gequiz,

Let me see if I understand what you are saying, and I'm going to assume that you have a manual gearbox.

(a)You are even-throttle at 70, you back out of the throttle to 60, but between 70 and 60 mph, your tach needle jumps up and 'spikes' to 3000-4000 revs, correct? And you are not messing with the gearbox, correct?

(b)The car itself does not speed up with your foot off the throttle, does it?

If (a) is happening, and you have visited the dealer only to receive an "it's OK" response, then go to another dealer who will listen to you. Be very specific about what is happening (e.g., is the car actually accelerating or is it the tachometer needle that is jumping, all while your foot is off the throttle).
If the car is NOT accelerating (only the tach needle is jumping about), then you have a problem with the tach or the sending unit from the ECU. I don't have the wiring diagram in front of me, but tell the service techie to check it out by putting an external tach on the car and measure it.

If (b) the car IS speeding up with the tachometer needle reading, then you have a safety problem that another dealer needs to address. He should first do an ECU dump/diagnostic. If you have cruise control, make sure this is happening with it off (be careful)...Then tell the service manager at the dealership to check the cruise control itself, separately.

I race Minis, and have a separate data acquisition system in my race car. It records RPM's separately from the stock tachometer, and I have found the stock tach to be inaccurate over certain rev ranges...but that's probably a separate issue.

Hope this helps!

Stephen.

 

It makes a big humming/revving sound as if it's trying to go faster, but it slows. If I gas it just a little bit at that point, the car downshifts and the rpms go down. It doesn't seem to be doing anything when the rpm spikes. Thanks for all your help! Still have to get a second opinion...Stay tuned.

 

I'm having the exact same problem with my 05 MC, auto. RPMs sit at 3-3.5 between 50-60mph, then back off around 70, but rev back up when the foot is taken off the gas and it slows to about 60. It's even hard now to "punch" it up past 50-55mph - seems almost as if it's stuck.
I've taken it in twice for service. The first time they "reprogrammed" the engine which seemed to work for a while, but the problem came back. The second time I took it in they initially said it was a new, known transmission problem and would fix it. Come to find out, when they drove it they supposedly couldn't reproduce the problem and so didn't do anything. They even told me it was normal and the car should be doing it.

However, they also said that if there's more than one person driving the car (like I have) the engine is always trying to accomodate the driving styles of both people - since it's a "smart engine." Are you the only driver or does someone else drive?

I seem to have less problems when shifting over to manual auto, but just to a lesser extent. I'd love to know what more you find out as my dealer pretty much is pointless at helping with this problem.