Low Vibrations After Driving Too Fast!

[MiraOwner]

after driving my Mira pretty fast last night (probably would have hit the highest speed yet).. today in the morning i feel the car to be smoother and the unpleasant engine vibrations at low RPM have died down a bit.. its a welcome change. but what really happened? is it good or bad?

[Elvis_Pil]

Sometimes a good thrashing does wanders towards unclogging an engine, knocking out a bit of the carbon deposits and maybe advancing up the engine timing, with the ECU self learning..

[heavyD]

  On 9/23/2010 at 7:25 AM, Elvis_Pil said:

Sometimes a good thrashing does wanders towards unclogging an engine, knocking out a bit of the carbon deposits and maybe advancing up the engine timing, with the ECU self learning..

What happens when the engine timing advances?

[Sumiya]

  On 9/23/2010 at 7:59 AM, Big_D said:

What happens when the engine timing advances?

Hi Big D

it Might increase the engine performance a bit, means Firing take place earlier than it is usually before piston reach to it's TDC. if it is too advanced you feel difficult to start too and also engine tends to knock a bit on tappet .and also increase engine wear..

thanks

regards

sumith

Edited September 23, 2010 by Sumiya

[Elvis_Pil]

  On 9/23/2010 at 7:59 AM, Big_D said:

What happens when the engine timing advances?

It means -engine ignition timing advances, that is the timing of the spark plugs firing. The correct ignition timing will enable the engine to burn the correct mixture of fuel and air during combustion- ensuring the highest possible level of power and economy. The ignition timing increases with engine revs- due to there simply being less time for whole process. In modern EFI cars the process maybe controlled by the car's ecu.

[heavyD]

  On 9/23/2010 at 8:57 AM, Sumiya said:

Hi Big D

it Might increase the engine performance a bit, means Firing take place earlier than it is usually before piston reach to it's TDC. if it is too advanced you feel difficult to start too and also engine tends to knock a bit on tappet .and also increase engine wear..

thanks

regards

sumith

  On 9/23/2010 at 9:36 AM, Elvis_Pil said:

It means -engine ignition timing advances, that is the timing of the spark plugs firing. The correct ignition timing will enable the engine to burn the correct mixture of fuel and air during combustion- ensuring the highest possible level of power and economy. The ignition timing increases with engine revs- due to there simply being less time for whole process. In modern EFI cars the process maybe controlled by the car's ecu.

So basically the ecu learns the way you drive and changes the timing? If so, would the ecu ever let the timing become too advanced? As to a point where it's bad for the engine? It must have limits I assume...

[MasterDon]

I recently had a problem with pre-mature "firing".My MG A kept overheating after about 30kms.I cleaned the radiator cores and changed the plugs and even resynched the twin carbs but it still kept on boiling.in the end it was the timing adjustment that did the trick.now all is well.

[Sumiya]

  On 9/23/2010 at 9:58 AM, Big_D said:

So basically the ecu learns the way you drive and changes the timing? If so, would the ecu ever let the timing become too advanced? As to a point where it's bad for the engine? It must have limits I assume...

Hi BiG D

Basically yes,

But Old cars having mechanical ignition timing requires manual set up for the crank timing and ignition timing basically with crank pulley and distributor.

most of the after market ECU allows user defined value to be set for ignition timing as

required by the user.those will work on presets ECU values.

thanks

Regards

sumith

[Elvis_Pil]

  On 9/23/2010 at 9:58 AM, Big_D said:

So basically the ecu learns the way you drive and changes the timing? If so, would the ecu ever let the timing become too advanced? As to a point where it's bad for the engine? It must have limits I assume...

No. the ECU does not 'learn the way you drive' - it corrects based on the conditions. If the ECU has not been tampered with and is in good working order, its highly unlikely that it will ever churn out a command that will be harmful for an engine (unless some sensor is bust).