[fencekey]

How can I tell the difference between the two?

I just increased boost to 16 to 17 psi and I'm on stock plugs. I feel hesitation/stutter at the upper boost levels and power goes down.

Also, would either of these conditions cause my check engine light to come on? I just installed my BCC and I think I hit fuel-cut a couple of times at just over 15 psi; the check engine light came on too. I hooked up the BCC power source to the unused seat heater fuse in the driver-side fuse box near the pedals. I used an "add a fuse" product that can deliver a max of 10 amps. Will this adequately power the BCC, which requires a 12v power source?

So what is it? A miss, detonation or fuel cut?

Thanks in advance

 

[parboy]

If you hit fuel cut you would know it. All your dash lights start going crazy and the car shudders. Try gapping your plugs down if you haven't already. If you are still on stock denso's at .044, try some ngk's at the preset gap of .032 and see what happens.

 

[fencekey]

Let me rephrase the question - Is it possible to get a check engine light just from a high speed miss?

I was able to get 16 to 17 psi before I felt what I thought was a miss and then the check engine light came on.

 

[aznsupra]

then that would be fuel cut..detonating or missing would not cause your car's check engine lite to come on.

 

[Josh S]

Did you adjust the voltage output of your BCC? BCC's do not come pre-adjusted, so if you just installed out right out of the box you may have a problem.

 

[fencekey]

I installed new plugs gapped to 0.34 and the missing went away. No check engine light anymore either. That is weird, considering I shouldn't have gotten a check engine light from a simple high rpm miss.

The BCC was preset (by a friend) at 4.3V for my 94 automatic. However, I did back it off about one full turn after I started having problems. Did I back it off too much?

Also, the power source for the BCC is the unused seat heater fuse, but the current to the BCC is limited to 10 amps. Is 10 amps enough power to adequately charge the BCC? Probably a stupid question, but just though I would ask.

I will most likely adjust the BCC upward (clockwise) by 1/2 turn and just leave it there.

 

[parboy]

The BCC was preset (by a friend) at 4.3V for my 94 automatic. However, I did back it off about one full turn after I started having problems. Did I back it off too much?

Also, the power source for the BCC is the unused seat heater fuse, but the current to the BCC is limited to 10 amps. Is 10 amps enough power to adequately charge the BCC? Probably a stupid question, but just though I would ask.

I will most likely adjust the BCC upward (clockwise) by 1/2 turn and just leave it there.

Backing it off that much was way to much. Follow the directions on the mkiv alternate site for tuning the bcc. It only takes a second to use a voltmeter and get it spot on. I believe that the bcc is fine anywhere between 6-12 volts, but dont quote me on that one. I seem to remember reading it though. Glad the new plugs/gap fixed the problem for you!