Mechanics

MISFIRING WHEN GOING UP A HILL

1994 Mitsubishi Lancer

Hello I have a 1994 mitsubishi lancer which misfires mostly when im going up a hill when the engine revs are low, if I but it up a gear it dosnt do it? Could you please help me
Thank you
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Bcool14
August 5, 2012.




Check plugs for excessive gaps, check ignition leads and coil as well, start here.
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Mhpautos
Aug 5, 2012.
Yeah I have replaced the plugs and leads. Also I have replaced the distributor cap and rotor and still haveing the problem

Tiny
Bcool14
Aug 6, 2012.
Coil, this sounds like an ignition fault under load.

Mhpautos
Aug 6, 2012.
Ohh ok so do you think if I replace the coil that should fix it?

Tiny
Bcool14
Aug 6, 2012.
When a car misfires under load, such as your problem like only going up a hill, this is normally an ignition related problem, as you have addressed the first items that would normally be looked at, that being plugs and leads, the coil is the next item that would be of interest, but before replacing the coil, I would do a comp test just to be sure all is good there.

Mhpautos
Aug 6, 2012.
Ok Thank you verry much

Tiny
Bcool14
Aug 6, 2012.
Just another thing that I find weird is when I am going up a hill, say im in forth gear and it is misfiring, if I put it down to third it dosnt misfire
Thank you

Tiny
Bcool14
Aug 6, 2012.
The engine is under more load in top gear, drop a gear and the revs increase less torque loading on the engine less load less chance of ignition break down. Basically the engine is straining in top gear, often called "lugging" you will experience pretty much the same thing trying to drive off in 3rd on the flat. The engine comps are extremely high when running, much higher than your cranking test, the ignition spark must jump the plug electrode and over come this pressure, the spark will always fine the easiest path to earth, so if the ignition system is under stress due to high torque loads, (lugging up hill) the spark will find an easier path to earth, hence the miss fire.

Mhpautos
Aug 6, 2012.
Ok thank you so if I do a comp test, woulde my lancer be obd2? Also the 18 pin obd plug in the car only has 3 wires coming out of it

Tiny
Bcool14
Aug 6, 2012.
I think it should be compliant.

Mhpautos
Aug 6, 2012.

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