VK 308 with a cold miss

[VK SL 3800]

Hi all,

My Vk berlina with a 308 has an odd miss, i dont think its a spark related miss but more of a lean miss on one cylinder or something. Ive done all the basic ignition side stuff like check plug gaps, rotor button and cap ect. All the plugs look the same and ive swapped a few around to see if anything happens but nope. It is just really throbs when accelerating and if i rev it on the spot its hard to describe but its not like a puff puff puff sound like when you unplug a lead cant really describe it. No vibrations or anything and it comes good as soon as you get it warmed up a little, carbie area sounds a little hissy but pretty sure thats normal for the 308, i couldnt find any vac leaks or busted hoses ect. Car is Bog stock with 122,xxx Km. Its just a little annoying and i cant work out why its doing it.

Also its got a massive flat spot right off idle (apparently its had it since new and the dealer couldn't fix it).

Cheers Ben

[Not_An_Abba_Fan]

Flat spot from idle is usually the accelerator pump. Either not adjusted properly or the cup is worn.

The miss would be fuel/air related if it only does it cold. Check the base of the carby, make sure the gasket is OK, make sure the spacer doesn't have a crack in it, check all the vacuum lines. It is usually not enough fuel or too much air, ie: vacuum leak.

[ari666]

get your timing light and while the engine is runnning, hook the pickup wire to each spark plug lead and see if there is a nice bright flash.

then hook up the timing light to number 1 while its cold. rev the engine and see where the mark moves to at around 3k rpm. from what you describe it may have too little advance or one of the plugs isnt firing.

[VK SL 3800]

Could not find any vac leaks, sprayed start ya bastard around the hoses to be sure but nothing happened. I will couldnt see anything obvious wrong with the gasket or cracks in the spacer. Ill have to buy a new timing light cause i ran my old one over.