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[T3] Fastback miss during idle update


<x-charset iso-8859-1>So when I bought the car two years ago the guy pointed out that the MPC to
the cold start valve was intentionally disconnected. Don't connect that, it
floods the engine he said. I happily took his advice while I wondered about
fixing it. Posted to the list and was told either a bad cold start valve or
wires reversed somewhere giving it constant power. Well in my travails
trying to iron out the miss during Idle I came across a spare intake for an
automatic square and switched the cold start valve in....continued to flood
the engine. when I unplugged it the idle improved a bit but still sounded
and felt too rich....fast forward to latest job...fixing the miss. So the
first thing I did was unplug that mpc, as I said it slightly improved the
idle, but still a miss and wanting to stall.

So I went out and bought a fuel guage per Muir pages 140-143, sliced off the
end and hose clamped it onto the rail test port..pressure reading 32 foot
pounds at idle, adjusted it down to 28 foot pounds by way of the regulator -
okay great! so the idle was missing because the pressure too high and
flooding overrich mixture.

well I went out and bought another set of bosch supers and screwed out the
old ones..black around the rims slightly wet but reusable - hell only 3 days
old. Put the fresh ones in and fired it up. Still a miss. Hooked up my
tach/dwell and measured the dwell. 49 degrees at idle , moving slightly to
50 degrees in the higher rpms. okay. tried to set the idle by the adjustment
screw. Now I could make an adjustment from between 800-900  up to 900-1000.
the needle moves evenly between 900 and 1000 during the course of the idle,
low end towards 900 for the miss and back up towards 1000 for the smooth. No
better than that. Took it around the block a few times and then back to the
curb. Idle just as bad missing as ever. read the voltage off the battery at
idle 13.5 even. At mid to high rpms it goes up to 14.0.

So the dwell & voltage seem okay, now the fuel pressure is at 28 pounds, yet
the idle doesn't quite yet. Miss as solid as if I've done nothing to the
car. I'll buy a new cold start valve and/or check the wires to the starter
but I do not think this will solve my miss. Am I right? Am I wrong? My God,
what have I done?

Chris

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