A strange misfire
#1
A strange misfire
I just got a strange misfire today. I had a fouled plug with my original plugs and drove it hard and that disappeared. This is a recent set of platinums that were installed. I also had a set of Accel COPs put in at the same time. Maybe have 2000 miles on everything. It doesn't throw a code yet but you can feel and hear one cylinder isn't up to snuff. It doesn't show on the vacuum guage as anything burnt like a valve. It's rather a steady reading with the idle RPM not varying more than 10 rpm either side of 580. To me it feels like something on the verge of quitting functioning. Any ideas?
#2
#3
#5
#6
It's fixed.
I found the problem finally. It was #3 COP. I took resistance readings from the contact point spring for the spark plug to either of the input terminals. Accel is a reading of 6.3 on the 200k scale and compared to a stocker of 5.2-5.6. The third coil I replaced read 4.3 and I figured that was the culprit before I started the engine to try it. This reading confirms why it wasn't a complete misfire. I'm just still used to complete misfires from single coil setups. I'm not at all a chebie fan but the coil per cylinder setup is ez as far as troubleshooting. Thanx to all for the inputs.
#7
Expect the others COPs to fail as well..
ACCEL COPs are worthless junk. Three have failed in 6 months. The first within a month of install, it completely shorted out sending the engine into safe mode. The other two failed within the last week, producing a misfire during acceleration at 1300-2000 rpm. The stock COPs are going back in tomorrow.
2006 Lariat F150 Screw
3.55 gears
22" w 305-45-22 Continental
Extang Fultilt Tonnoue
Flitch Fuel Catalyst
Royal Purple Lubricants
Corsa Sport Exhaust
2" Eibach Shakle Kit
Troyer Elec cooling fan
MAD Fan Controller
K&N Cold Air Intake 632556
SCT LiveWire Tuner Troyer Tune
Dynatech headers
Accel COP
Granetelli COP connectors
2006 Lariat F150 Screw
3.55 gears
22" w 305-45-22 Continental
Extang Fultilt Tonnoue
Flitch Fuel Catalyst
Royal Purple Lubricants
Corsa Sport Exhaust
2" Eibach Shakle Kit
Troyer Elec cooling fan
MAD Fan Controller
K&N Cold Air Intake 632556
SCT LiveWire Tuner Troyer Tune
Dynatech headers
Accel COP
Granetelli COP connectors