View Full Version : Car sputtering at high rpms?

07-31-2003, 03:01 PM
Acura Integra GS-R motor

MSD Digital 6
Blaster HVC Coil
Modified Distributor Cap

The max rpm limit is set at 8k. When I get to around 7k, the car slightly sputters/hesitates. Funny thing is that this only happens occassionally. Sometimes I can go to 8k in 1st-3rd gear just fine.

Any ideas?

07-31-2003, 05:24 PM
Sounds like a secondary voltage breakdown. The reason you see it more in high gears is because that is when the engine load is highest. What spark plug wires are you running? Do you know what the resistance per foot is on them? Generally when you have a missfire like you described it is either the coil wire, spark plug wires or on the coil tower. Look at the coil tower real close and make sure there is no carbon tracking on the side of it. If you see a black line running down the side of the tower then you need to replace the coil and coil wire.

MSD Tech1

07-31-2003, 08:07 PM
I'm running stock plug wires, not sure what the resistance per foot is. Do you think the brand new MSD coil could already be going bad? I've barely had it in for a month!

EDIT: Checked the coil tower - no carbon tracking. I'll try and replace the spark plug wires. Any recommendations?

08-01-2003, 10:15 AM
I think the spark plug wires should be your best bet. Replace them with a Helically wound suppression type wire with low resistance.

MSD Tech1

08-01-2003, 10:17 AM
The symptoms that you are having may be due to bad wires. The only other thing that I could think of would be leaning out at top end. If you have an adjustable fuel pressure regulator increase the fuel pressure and see if this helps.