joneseythedog
Senior Member
Dear All
My 1995 C180 is a tad lumpy when idling at around 750rpm. Struggles a bit going uphill too, and sometimes sounds a bit tractor-like.
At some convenient time I will take it to the local MB dealer to have a quick check-over, but in the meantime have put a new air filter in and have decided to replace the spark plugs too, as they aren't too expensive and I don't know when they were last done (bought the car a few weeks ago. FSH, but nothing to tell me what was done each time).
I have two alternatives in my posession: Bosch FR8 DC+, with a gap of 0.8mm, and NGK BCPR6IX-11 irridium with a gap that seems to be a little over 1mm. The Bosch were specified in the flip-flap thing at Halfords, and the NGKs came from sparkplugs.co.uk, where the on-site questions arrived at this type.
Anyway....My Haynes manual tells me the gap should be 1mm, although I have seen 0.8mm quoted in several threads here. The Bosch gap of 0.8mm seems very specific.
What I would like to know is:
* What is the correct gap?
and
* Is the gap determined by the spark plug type or by the car? The NGK plugs are a fancy type. Are they designed to work to their own gap?
Any thoughts would be appreciated
Andrew
My 1995 C180 is a tad lumpy when idling at around 750rpm. Struggles a bit going uphill too, and sometimes sounds a bit tractor-like.
At some convenient time I will take it to the local MB dealer to have a quick check-over, but in the meantime have put a new air filter in and have decided to replace the spark plugs too, as they aren't too expensive and I don't know when they were last done (bought the car a few weeks ago. FSH, but nothing to tell me what was done each time).
I have two alternatives in my posession: Bosch FR8 DC+, with a gap of 0.8mm, and NGK BCPR6IX-11 irridium with a gap that seems to be a little over 1mm. The Bosch were specified in the flip-flap thing at Halfords, and the NGKs came from sparkplugs.co.uk, where the on-site questions arrived at this type.
Anyway....My Haynes manual tells me the gap should be 1mm, although I have seen 0.8mm quoted in several threads here. The Bosch gap of 0.8mm seems very specific.
What I would like to know is:
* What is the correct gap?
and
* Is the gap determined by the spark plug type or by the car? The NGK plugs are a fancy type. Are they designed to work to their own gap?
Any thoughts would be appreciated
Andrew
