Gear or Speed hanged

[sapporobier]

Can I ride on this thread & ask fellow bros & sis something? I was driving my new C180 earlier this morning, I was behind this car that was hogging the road...at about 30km/hr.

Then this car filtered away, as with any normal driver, I stepped on to increase the speed of my car. But somehow my car was stuck at around 30-40km/hr with a rpm of about 3000. the speed just won't increase & the rpm hanged there, even after I released the accelerating pedal. my heart skipped a beat cos there was a car tailing behind me rather close. I didn't know what to do & tried tapping on the brakes slightly. That sort of cleared the "hanged rpm" & it dropped slightly to 2000+rpm. I accelerated few secs later & everything went back to normal.

This was the 2nd time I encountered such incidents of hanging rpm. Was it my driving style that needs to be changed or something that I've missed out? Freaking scary when the car can just "hanged" halfway on the roads. Any advises?

not sure your is the turbo or kompressor. My experience on the c180 kompressor was that going at 20 - 30 kmh before doing right turn at junction, when time to turn could not accelerate. Still stuck at 30 kmh. Was lucky oncoming car far away. Was on the E mode. My guess is that it got stuck on the second or third gear. If it happens again, i will manually push down one gear, then rev it.

[jtang]

This is called a flat spot....particularly at E mode. This is less pronounced at S mode. The flat spot can removed by a tuner..that means modding the car.

[Magneto]

This is called a flat spot....particularly at E mode. This is less pronounced at S mode. The flat spot can removed by a tuner..that means modding the car.

Great news ! Thus C&C can Retune for us. Thanks jtang.

Mag SmiLing

[Mb225]

Great news ! Thus C&C can Retune for us. Thanks jtang.

Mag SmiLing

confirm bo that they will retune?

[BlackSheep]

I did a search & OMG, this "flat spot" problem started way back 2003?!?

http://www.benzforum.com/forum/showthread.php?t=7042

[hatch]

Could also be e speed limiter gotten activated.

Happened a couple of times when I gotten e car.

[sapporobier]

No, did not activate the speed limiter.

In my opinion, this issue is similar to aviation term of aerodynamic stall, where the plane is actually going nowwhere before it drops and crashes.

Did a little google and found this on wikipedia.

A compressor stall is a situation of abnormal airflow resulting from a stall of the aerofoils within the compressor of a jet engine. Stall is found in dynamic compressors, particularly axial compressors, as used in jet engines and turbochargers for reciprocating engines.

Compressor stalls result in a loss of compressor performance, which can vary in severity from a momentary engine power drop (occurring so quickly it is barely registered on engine instruments) to a complete loss of compression (compressor surge) necessitating a reduction in the fuel flow to the engine.

Modern compressors are carefully designed and controlled to avoid or limit stall within an engine's operating range. Stall was a common problem on early jet engines with simple aerodynamics and manual or mechanical fuel control units, but has been virtually eliminated by better design and the use of hydromechanical and electronic control systems such as Full Authority Digital Engine Controls.

[Cklasse]

Aircraft stall is when the angle of attack is too high that results in lost of lift due to disturbed airflow over the wing.

Certainly compressor is basically many little wings rotating along an axial, stall will happen. For this reason, aircraft engines are designed to tight tolerance for blade to case gap, blade angles are tightly controlled to prevent a surge, which is air flow getting disturbed and back flowing from rear to front.

However, in the kompressor engine, the supercharger is a scroll type pump, that is it's a twin screw rotating to compress the air and there are no tiny wings to produce the stall effect.

By this construction, I believe the stall theory doesn't exist in the kompressor engine.

[sapporobier]

You are right in that description. But from my drive, it feels like a momentary loss of power, despite stepping harder on the accelerator.

Anyway the drill for me is to knock down one gear and then accelerate.

[BlackSheep]

You are right in that description. But from my drive, it feels like a momentary loss of power, despite stepping harder on the accelerator.

Anyway the drill for me is to knock down one gear and then accelerate.

Yes I felt the loss of power too. How you knock down one gear? Sorry I know this is a super noob question hehe. I just stepped on the brakes briefly when it happens to lower the rpm cos I really don't know how to deal with it.

[Cklasse]

Just push the gear lever to the left once to drop gear.

[sapporobier]

Then don't forget to push the gear lever to the right for about 2-3 seconds, after getting your control back, to set the gear back to auto, if not your gear will be stuck in manual mode.

[BlackSheep]

Then don't forget to push the gear lever to the right for about 2-3 seconds, after getting your control back, to set the gear back to auto, if not your gear will be stuck in manual mode.

From a super noob again...so I should shift the gear once to the left, then when I feel the power is back & speed increased, I shift the gear stick to the right again? Just by doing that it will switch back to auto gears? So while shifting to both left & right I should still step on the accelerator pedal right? I have not tried manual modes at all for the cars that I had driven so far...paisay if I really sound really darn dumb here...

[sapporobier]

From a super noob again...so I should shift the gear once to the left, then when I feel the power is back & speed increased, I shift the gear stick to the right again? Just by doing that it will switch back to auto gears? So while shifting to both left & right I should still step on the accelerator pedal right? I have not tried manual modes at all for the cars that I had driven so far...paisay if I really sound really darn dumb here...

yes, once shifted down, you will see D change to D2 (or whichever is 1 gear down) on you console, then step accelerator, should feel the power, let go accelerator, then shift gear right for about 2 seconds, you will then see D2 change to D. Remember don't shift to neutral when you are moving, may spoil your gear.