JSe420

So i have a misfire in my 420. The car runs and drives perfect when up to speed on the road, but when i come to a stop, it skips pretty bad, sometimes even surging. It also starts real rough when cold. So far i've replaced; Plugs, wires, distributors, and rotors. Also, i have inspected my wire harness and its in good condition. Could this be a problem with one of my coils? Any help is appreciated

JSe420

anybody?

Saijin_Naib

Alright. Lets see.
What plugs?

JSe420

8 Spark plugs... but it was doing this even before the change of the spark plugs and ignition wires.

Saijin_Naib

Hrm. What specific model spark plugs? We can not use resistor plugs in our cars and the proper gapping on the plug is VERY important.

Have you changed/checked the thermostat?

JSe420

Funny you should ask i have had a new therm. kit in my back seat for like a month i just havent gotten around to doing it yet. But that wouldnt be my problem....or would it??

Saijin_Naib

Probably not, but it may need doing anyway. I found that when my therm was bad my car ran much much nicer. It was running on the warmup mix constantly as the engine never got over 80C or so :P

Gimme the stats on your plugs sir, I am suspecting them.

JSe420

i know what your gunna say about my bosch plugs lol. But honestly, we use bosch plugs daily at my shop and we have never had a problem with them. Ignition wires are another story...

Im suspecting a coil that could be on its way out because the car runs perfect when rpms are over 1200.

Saijin_Naib

Bosch are fine so long as they are not Platinums and not resistor plugs. They also need to be gapped properly. Please provide the plug model :P

JSe420

they are long gone, i threw all the old boxes out and have since made a dump run I will have to pull one out. But if it was the plugs it would have more of a constant skip even at higher rpms.