Proton runs like a tractor

[dcawkwell]

hi group,

Got a problem with my proton 1.6 wira. They have a mitsubishi
engine.
This suddenly started happening.
When starting up from cold the engine runs more like a tractor.
Very little power and uneven running. After 5 minutes
of running and warming up the engine then runs fine.
Warm starts and the engine is fine.

I have changed the spark plugs but this hasn't cured it.
Next up I will be checking the valve clearances.

Any other suggestions as what the problem could be MAP sensor/coil pack?

 

[Mursal]

ECU coolant temperature sensor

Misfire at low temperature?

Usually tappets cause more trouble as the engine warms up, but worth checking

PS Dont knock tractors till you try them

 

[dcawkwell]

ECU coolant temperature sensor

Misfire at low temperature?

Usually tappets cause more trouble as the engine warms up, but worth checking

PS Dont knock tractors till you try them

My other vehicle is a JCB. Best toy I've ever had.

 

[Burnerman]

I'd go for the coolant temp sensor too - there's a chance that its making the engine think that its warm when its actually cold......just the same as trying to run the engine without choke in the good (bad) old days!
A coil pack fault would result in a continuous misfire, with the management light on, but the MAP sensor (if it has one) could give reluctant to rev symptoms, but that would be at any temperature.
John