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-   -   RPM shoots up when clutch depressed (https://www.team-bhp.com/forum/technical-stuff/34083-rpm-shoots-up-when-clutch-depressed-5.html)

It looks like a clutch position sensor , Probably stuck or mis aligned sensor can make the car do this.

Hi All,

It looks like the problem may have been fixed. I took my car to the A*S*S for the routine checkup and got it serviced. The throttle body was cleaned during service. However, the problem still persisted.

A second visit to the ASS made them bring out the OBD Tool. The SA connected the device to the port below the dashboard and immediately an error code flashed which translated to "Throttle Positioning Sensor Error". The SA cleared this error and checked again for any other error codes. There were none. We then went for a short 2 km drive through narrow roads, heavy traffic and the works, where pressing the clutch pedal and changing gears and doing some "clutch driving" becomes necessary.

On this drive though, the car behaved itself. We made sure that it did not repeat and tested various ways of causing the error to pop up again. Still .. nothing. It looks like something was wrong with the sensor and clearing the error code (and probably having the TB cleaned) did the trick.

The SA has informed me that if the problem should recur, they may have to change the Throttle Positioning Sensor on the car. I will do some more driving during the weekend and report back here...

The potentiometer in the throttle position sensor is adjustable in many cars. Please see if that is the case with the Accent too. A slight adjustment of the TPS can see through this problem and can save you the cost towards a new TPS.

Also, a clogged air filter, dirty throttle body and a failing thermostat in the cooling system can lead to higher engine RPMs.

Regards,
Saket

Looks like the problem is back. I had a quick drive yesterday and whenever I had to press the clutch, the rpm went up to 2500, though it didn't hit the 3000mark. Still, the issue is unsettling while driving and quite dangerous too. I almost did a wheel spin start after a signal and startled some of the other people around me waiting in the signal. If I hadn't pressed the clutch fully again, who knows, I could have hit the guy in front of me.

Spoke to the SA and fixed up an appointment on Monday morning. He said another i10 has come in with the same problem. He also said he will try swapping the TB with another car's and the TPS too. Based on this swap he said we'll see what can be done.

The clutch, but in my case if i pump the brake pedal when the car is idling(no reason for doing so, but still) the RPM rises a lil' bit. Can't know as i don't have a tachometer, but the car definitely revs up a little when i do so. Is it because of the brake booster working or something? It's a '09 WagonR.

Finally, the problem seems to have gone away. The SA saw that the error code had appeared again on the scanner. He reset it and that seems to have fixed it for good. Could be a blown fuse or a disconnected battery that may have messed with the chip/sensor memory settings as per the SA. As I don't recollect replacing any fuses I am guessing its the latter. Anyways that's the end of the problem ...thanks all for your guidance and inputs.

I am too facing the same problem with my Ikon 1.6.

Each time I press the clutch to engage the gear, the RPM would increase to ~2000 and then once in the gear, the RPM would drop.

Especially this is happening while AC is ON and in slow moving traffic i.e. while changing between 1st/2nd/3rd gear.

If i switch off the AC, most of the time the issue will not appear.

During regular service, I mentioned this to my mechanic, he checked everything and said it could be due to faulty RPM sensor and i should change it.

What else can cause this issue?!

Any reverts?! I am still facing the problem with my car...

Also one more information required.. Any local garage who can do complete diagnostic check of engine and reset ECU errors...

Does removing battery for 1~2 hrs will reset all the errors in ECU?!

Instead of depressing and holding the clutch, shift the car into neutral and see if the problem persists.

Also, whenever the RPM increases to 2K (when the clutch pedal is depressed), switch off the A/C and notice what happens to the RPM.

Check it and report back.

I have done that already.... If i put it on neutral while changing gears,still RPM shoots up if clutch is pressed.. It comes down only after releasing the clutch...

If i switch off the AC, while RPM is shooting up... it comes down to normal gradually not immediately...

Even if AC is switched off while driving i face this problem occasionally...

Also if i pump the clutch 2~3 times while RPM goes up... it comes down to normal...

I had faced a similar problem with my Ikon 1.6. I no longer own the Ikon. It took Metro Ford, Lingarajapuram a couple of days to identify and address the issue. I demonstrated the issue with their senior technician behind the wheel. Even though he understood what was happening, it was difficult to narrow down on the problem. I suggest you show it to them. The service advisors know nothing about problems like this. I spent Rs. 2000 which was billed as labor. No part replacement was shown. I can't say if any was done and not put on the bill. At the end of day, the problem was solved for me.

Changed the clutch plates during routine service. After that RPM issue disappeared :).

I had the same problem on my Ikon Flair 1.3 about a year back but a bit different way, it used to increase when clutch was pressed and after changing gear used to go down to 0.2 RPM level and come back to normal. It was like car would halt and again start. It was more when the car used to get hot means after a 15-20 mins drive or thru B2B traffic. It was very frustrating for me, Checked everything all sensors, changed the RPM sensor but the problem reduced but not completely gone. One day i gave it to another known mechanic to check which sensor was faulty. He got another ford ikon same model and replaced all the sensors to check but failed to find any fault. At last i had to send it to Ford service center and when they put the car on scanner machine they found out a small cut in the injector wires, that was because of Rat chewing it a bit. It was like out of 10 wires, 2 had been cut and there was less power to the injectors causing malfunction. Had to replace that full injector cable set which costed about 10000/-, but had no alternative. After that it is running smooth till today. No problems.

WOW! Rs. 10,000 when all you needed was a little wire and a couple of crimps. What will they do if a rat chews on some wires again, change the harness once more?!

Nice illustration of what I have been saying in many threads: Always read the codes first! Without codes in many cases on a modern car it's just trial and error by endlessly replacing parts. Run a mile from car mechanics that think they can troubleshoot your car without a proper OBD scanner and analyzer. Preferably a manufacturer and type specific one.

Jeroen