Wrong spark plugs??

[paisesmediterraneos]

Hello, I am David from the south of Spain, I recently bought a 2003 Caterham Seven 1.6 k series roadsport. When I depress the gas pedal the car goes giving pulls, and more when the car is cold. When I depress the gas pedal in neutral everything is ok, but when I engaged a gear and begin driving, the car begins giving pulls. I checked the spark plugs and the car has NGK PFR6N-11.  I was checking at NGK web and they recommends for the car NGK BKR6E.

Do you think the car is doing this because it has the wrong plugs??.

 

Thank you very much, best wishes.

[Jim 123]

What gap are your plugs currently set to? Also at the ends of each plug where you get the spark (the electrode), are all showing the same colour? Remember you can upload photos to this site which maybe helps if translation is a problem.

Do you get the "pulls" across the full range of engine revs e.g. Say in 3rd gear from 1,000 all the way to 6,000 rpm?

[paisesmediterraneos]

 

 

  Hello Jim,

the plugs are now 1 or 1.1milimeters gap, I found in the NGK catalogue that the plugs it has now (KGK PFR6N-11) are recommended for the engine 1.8K but for the engine 1.6K they recommended  different plugs (NGK  BKR6E).

The pulls finish at 3.000rpm more or less, but sometimes (more when it´s cold) it´'s difficult to arrive driving to 3.000rpm...a lot of pulls.

 

Regards, David.

[paisesmediterraneos]

I realized reading many posts that there use to be many problems with the fuel pump in Caterhams...do you think the pulls I am noticing could be because a fuel pump failure??. Sometimes when I stop at traffic lights the engine idle is a little unstable.

[Jim 123]

PM sent
 

[paisesmediterraneos]

Jim, thank you very much for helping me with the problem.

Thanks to you I learnt that the problem of the car is called "misfire" in english, I didn´t know about this term, this is why I was writing that the car was "giving pulls".

Thanks to you I also found that the origin of the misfire was in the Lambda sensor.

Best wishes from the south of Spain.

[revilla]

I think we kind of guessed what you meant by "giving pulls"  Glad to hear Jim 123 got you all sorted.

[Jim 123]

Could somebody give David the correct part number and a supply source for a replacement Lambda for a 1.6 K Roadsport please. My car is a Ford engine.

[revilla]

For EU2 engines (distributor type), Rover MHK10006

For EU3 engines (two coil packs on top of the plugs), Rover MHK100840

Item number 8 here: https://rimmerbros.com/Item--i-GRID001113The only difference between them is the connector, to match an EU2 or EU3 loom.

[paisesmediterraneos]

Thank you Revilla for the technical information about the Lambda sensor; mine is EU3, I found for selling in Spain, with the reference you gave me, a sensor built by Magneti Marelli with a nice price.

 

 

[revilla]