civikdude

OK. So the car is barely running. Throwing CEL P0300 for random/multiple cylinder misfire detected, and all of P0301-304 (cylinder 1-4 misfire detected). The hesitation occurs whether engine is cold or warm, regardless of throttle position (although more noticeable only at part throttle), and at any RPM. Acts like it wants to quit at idle, but manages to stay running by constantly adjusting the engine speed. Took it to Honda but they were unable to diagnose due to the presence of aftermarket stuff, hinting that the problem may lie with fuel. B&M fuel pressure gauge reads 40 lbs at idle.

Now here's the thing that catches my eye: when I put a simple timing light on any of the spark plug wires, (while at idle), there are very noticeable pauses in the sequence of flashes. This would indicate to me that the problem is ignition-related, that whatever delivers the spark is not working "full-time". I have replaced the wires (twice), cap and rotor with OEM, to no avail. Does this leave me with a failing ignition coil? What about the ICM (igniter)? Both, perhaps? Or, even worse, none of the above? Has anyone experienced these conditions and can speak to this? The Si is at 96,000 miles.

<U>Setup</U>
B16A2, stock internals
JR supercharger, 10 lbs boost
SMC-500 MAP controller (hack)
JR boost timing controller
NGK BKR7E plugs gapped at .028
Stock ignition
RC 440cc injectors
Walbro 190 lph fuel pump
Stock fuel lines, FPR, rail

<U>Replaced</U>
Ignition wires, cap and rotor (OEM)
Plugs
PCM (swapped with another)
Fuel filter (OEM)
SMC-500

Please help!!

Sack Master

Sounds like low coil output. All that stuff on an obd-II motor has to make that ecu go haywire. Did you ever think about throwing an ignition system on that beast and try to burn off the excess fuel going in there. May also want to check your o2 sensor and map sensor. Could be making that thing run overly rich especially at low rpms. Just a couple thoughts to add.

PnX-R

Here's how I'd go about diagnosing it. I'd pull out the service manual and test the Igniter (ICM).

zlaja_gsr

iTrader: (1)

Hmm i had a similar problem with the wire that grounds the coil. That wire comes of the main harness and is located close to the cap where it is bolted together with a 10 mm bolt. Tighten that up a little bit, not too much bc it tends to snap. If that doesnt work my money is on the igniter.
P.S. check the timing, ignition and main