[jay116]

I think the problem am facing can be called engine braking as explained by Planet_rocker. Any known causes? Solutions?
I am thinking of cleaning the fuel injection system using Liquimoly or BG and also move to fully synthetic lube , like Castrol Edge.
A friend of mine suggested that I should reset the ECM once to default state.
But I still have a feeling that its the throttle sensor which may not be working all that well and therefore is allowing a rapid rate of fall which is causing the engine to brake in lower gears, this does not happen in 4th gear even with the AC fully blowing.

Any ideas friends?

[mahadev_kc]

Hi,

Off late my Palio 1.6 Sport is behaving erratically. After starting the car, if I press the clutch, the rpm raises from 900 to upwards of 3000. If I move the car then the rpm will come down and whenever try changing the gear by pressing the clutch, then rpm will again shoot upwards of 3000.

throttle body cleaned up twice, but of no help.
Any suggestions to solve the issue?

Thanks in advance.

[SunnyBoi]

Originally Posted by mahadev_kc

Hi,

Off late my Palio 1.6 Sport is behaving erratically. After starting the car, if I press the clutch, the rpm raises from 900 to upwards of 3000. If I move the car then the rpm will come down and whenever try changing the gear by pressing the clutch, then rpm will again shoot upwards of 3000.

throttle body cleaned up twice, but of no help.
Any suggestions to solve the issue?

Thanks in advance.

Have you got the throttle cable checked for sticking?

Disconnect the negative terminal of the battery and connect it back after 30 minutes. An ECU Reset might help.

[planet_rocker]

Replied to Mahadev's PM

This shouldn't have happened unless the IAC Valve is damaged somehow or, there is more air being fed in to the throttle body through the IAC Valve.

1. idle RPM stays at 850 +/- 50 after warm up

2. check for excessive hissing sound around the throttle body (leak around the IAC)

3. Reset the ECU and do a throttle relearn

a. reset ecu by disconnecting battery over night / 5minutes (whichever suits you )

b. connect the battery and start the car - do not touch gas pedal - wait for 30 secs and switch off - wait for 30 secs - start the car and wait for 30 secs - switch off - wait for 30 secs - start the car and wait till the car warms up and radiator fans runs (after around 15 minutes)

4. go out for a drive and see

Keep us posted

Regards

Surya

Originally Posted by SunnyBoi

Have you got the throttle cable checked for sticking?

Disconnect the negative terminal of the battery and connect it back after 30 minutes. An ECU Reset might help.

A sticky cable will always give an erratic idle. IMO, it is related to the ECU. Like you mentioned, resetting the ECU should help (y)

[mahadev_kc]

Thanks all.
We did the ECU reset, but it is still happening.
About leakage, we will try to check it tomorrow.
This problem was there for long. some-times rpm was normal during acceleration and de-acceleration. After this, whenever there is a press of clutch, rpm will raise more than 3000rpm.

Thanks again for the help.

[planet_rocker]

Originally Posted by mahadev_kc

After this, whenever there is a press of clutch, rpm will raise more than 3000rpm.

Try and check if the accelerator cable is coming in way when the clutch is pressed in the foot-well.

[paragsachania]

Not sure if the 1.6 Petrol also comes with a clutch switch like the MJD. You may want to remove that switch (Located behind the clutch pedal) and check for its wear and tear too.

Second thing I would check is the Idle Air Control Valve on the Throttle body. If you mention that it was cleaned, It is more likely a case where even IAC would have been cleaned.

[amit_mechengg]

Check the stepper motor in the throttle body. Hook the ecu scanner and do the process of stepper motor reset. Also do a zeroing of self adaptation before doing the above step.
This all leads to problematic throttle body/sensors in the throttle body

[msaudf]

Originally Posted by mahadev_kc

Hi,

Off late my Palio 1.6 Sport is behaving erratically. After starting the car, if I press the clutch, the rpm raises from 900 to upwards of 3000. If I move the car then the rpm will come down and whenever try changing the gear by pressing the clutch, then rpm will again shoot upwards of 3000.

throttle body cleaned up twice, but of no help.
Any suggestions to solve the issue?

Thanks in advance.

You could try to disconnect the power connection IAC (Idle Air Control) valve and see if the problem persists, I mean its something you could do to diagnose the root cause of the issue. A sticking IAC valve could cause this problem. But if this turns out to be the culprit, Dont just replace the IAC, Because its controlled by the ECU based on signals from the Clutch Pedal Position Switch, and other sensors that put a load on the engine while its running at idle.

This is just a hunch my friend, just some DIY diagnosis before you go in for any expensive replacements.
Cheers Good luck

[mahadev_kc]

Originally Posted by planet_rocker

Replied to Mahadev's PM






A sticky cable will always give an erratic idle. IMO, it is related to the ECU. Like you mentioned, resetting the ECU should help (y)

Thanks a lot for the info. I did as planet_rocker said. Thought issue was resolved for around 10 kms drive and when AC is switched ON, the RPM started behaving erratically.

I also see that all of sudden RPM is going down to zero, when I press the clutch to change the gear.

And I hear a hissing sound near the IAC valves.

I also see that IAC senor is fixed to the throttle body.

Next step would to visit the service center and as suggested by everyone get the IAC valve and MAP sensor.
There was one Crank sensor I heard. Is this issue related to it?

Thanks in advance.

[h14]

Originally Posted by mahadev_kc

Thanks a lot for the info. I did as planet_rocker said. Thought issue was resolved for around 10 kms drive and when AC is switched ON, the RPM started behaving erratically.

I also see that all of sudden RPM is going down to zero, when I press the clutch to change the gear.

And I hear a hissing sound near the IAC valves.

I also see that IAC senor is fixed to the throttle body.

Next step would to visit the service center and as suggested by everyone get the IAC valve and MAP sensor.
There was one Crank sensor I heard. Is this issue related to it?

Thanks in advance.

Have you checked the injectors? One of my friend had the same issues of erratic RPM and in second gear the rpm would almost die. Tried various options by even swapping the throttle body and eventually it was narrowed to a faulty injector. He then replaced the injector and the issue was resolved. More details on his issue in here

[mahadev_kc]

Thank you all for your comments.

With all these conditions of the vehicle, we went to Yercaud during 25-Jan-2015.
While returning from Yercaud, the car's power was not increasing beyond 80kmph. This is onwards from Krishnagiri to Bangalore.

Some-how drove it to home and next time went straight to Venkatesh.
Venkatesh said that engine has misfire and after putting the examiner, it was the injector coil + RPM sensor was the culprit.

Both are replaced and car is running fine.
The problem of RPM raising suddenly when the clutch is pressed is also attributed to Throttle sensor, as IAC valve could not be cleaned as it is not a removable part.

Since the starter was also showing the age, as some-times warm start does not happen and had to wait for 5 to 10 minutes before the car starts. This problem was attributed to solenoid inside the starter.

I had ordered a starter from 99rpm, which they sent. But after putting the starter in the vehicle and after 2 days, the starter motor also went kaput, as bush housing is gone. Now waiting for the replacement from 99rpm.
Now the car is running from old starter motor.

The RPM raising issue is still present, which Venkatesh says will go after changing the throttle body.

I've one Crank RPM Sensor with me for 1.6 (in Bangalore), whoever want it pls let me know.

[mahadev_kc]

Hello All,

Since last change of ignition coil and RPM sensor, the car was fine for 3 days. Then I observed that, after driving the car from cold to around 2 kms, the engine is missing, and whole vehicle sputters or shudders at idle and rpm hovers around 400-500 rpm range and there is no power at all.

If I press the acclerator, only engine rpm raises but not power. This happens only after the car driven around 2 kms from cold. If the car is started again after 2 kms, I see the same behavoiur of engine missing.

Is the ignition coil + rpm sensor go bad after using only 3 days ???

I've changed the dying battery which is around 4.5 years, but the engine missing and behaviour is not changed at all.

Pls help.

Regards,
Mahadev

[msaudf]

Originally Posted by mahadev_kc

Hello All,

Since last change of ignition coil and RPM sensor, the car was fine for 3 days. Then I observed that, after driving the car from cold to around 2 kms, the engine is missing, and whole vehicle sputters or shudders at idle and rpm hovers around 400-500 rpm range and there is no power at all.

If I press the acclerator, only engine rpm raises but not power. This happens only after the car driven around 2 kms from cold. If the car is started again after 2 kms, I see the same behavoiur of engine missing.

Is the ignition coil + rpm sensor go bad after using only 3 days ???

I've changed the dying battery which is around 4.5 years, but the engine missing and behaviour is not changed at all.

Pls help.

Regards,http://www.team-bhp.com/forum/newrep...eply&p=3646730
Mahadev

Electrical parts can go bad without any warning at times, but just three days is just absurd.
I remember in your earlier posts you mentioned the starter motor was showing its age and was replaced. Did you check the Alternator?
I mean you just replaced the battery and the car ran fine for 2 days with the new coil and sensor and battery, so maybe its just lacking the voltage or amperage that is needed and hence misfiring.
I understand the car runs fine for the initial 2kms or so until its warm, so maybe when the engine warms up and the cooling systems put a load on the alternator, it could be weak and not be able to keep up with the load. it could be a simple worn carbon brush which is not a complicated replacement for a trained electrician.

[mahadev_kc]

Originally Posted by msaudf

Electrical parts can go bad without any warning at times, but just three days is just absurd.
I remember in your earlier posts you mentioned the starter motor was showing its age and was replaced. Did you check the Alternator?
I mean you just replaced the battery and the car ran fine for 2 days with the new coil and sensor and battery, so maybe its just lacking the voltage or amperage that is needed and hence misfiring.
I understand the car runs fine for the initial 2kms or so until its warm, so maybe when the engine warms up and the cooling systems put a load on the alternator, it could be weak and not be able to keep up with the load. it could be a simple worn carbon brush which is not a complicated replacement for a trained electrician.

Thanks. Here is the complete log of events to land into this problem.

1. The car starts up in cold, but not in warm. During crank, I hear only a sound of "click". So related to starter and other mechanic said that valeo starter motor parts not available and hence replace the starter motor.

2. On one fine day, I see that engine is misfiring, where no engine power though raise in engine rpm in any gear. In idle condition, the engine rpm hovers around 200-400 rpm, with shudder and whole car body shaking. In this condition I drove around 60kms to reach home.

3. Now shown the same to Venkatesh (Bangalore), who checks with analyzer that ignition coil and RPM Sensor went kaput.

4. So put a new ignition coil + RPM sensor + new starter motor.

5. Everything is fine and as original tune.
6. After 2 days, the new starter motor that was put in went kaput. When checked, the starter motor wheel bush is the culprit. Luckily I had the old starter motor and shown it to another electrician, who finds that starter motor solenoid is gone kaput. He replaced the solenoid with FORD part as he says both FORD and FIAT starter motor have same solenoid. After replacing the solenoid, car starts fine.

7. After 2 days, I see the same problem of misfiring, car shuddering, no engine power with rpm raising in any gear. This was with new ignition coil put in. So, thought this could be because of battery gone weak (as it was 4.5 years old and when engine is cranked, the battery voltage was dropping to 9V instead of 11v as in a healthy battery), so changed to a new battery. And driven the car for around 10kms. Here it is felt as if it is a new car, with everything proper.

8. After driving around 10 kms, the engine started misfiring again. So a very serious problem.

9. Left the car at home for a day and started again after a day. The engine cranks very well with proper rpm and engine power. Drove it for 2 kms, then I see the same problem of engine misfire, less power from engine though raise in RPM.

Now whenever I start the engine, the whole car shudders, and RPM hovers around 200-400rpm in idle, so I've to rev it up to prevent stall and again no sufficient engine power with raise in RPM in any gear.

10. Got hold of an ELM327 analyzer from http://www.devtechblore.in/index.php...roller=product and connected to the car.

Following is the screenshot I captured. When all these errors were erased and the car started again to proper engine note. Here just driving after 1/2 kms, the engine started misfiring.


11. All through these, when the engine note and power was fine, I see occasional raise in engine RPM to around 4000 whenever the clutch was depressed, but vanishes when I release the clutch. Some times, when in idle, the RPM started varying between 900 to 3000 like a sine-wave.

Kindly help.

Also note that, the alternator was repaired 4.5 years ago, as it was not charging the battery.

Also, the rats chew some part of this wire. This wire is connected to a sensor that is connected to a coolant tube. I think it may be the temperature sensor, though I'm not sure. Next time, I will click a photo of it and will post here.