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<x-charset iso-8859-1>First off, your cold start valve isnt the problem... Im assuming you have a 70 or later.. its the thermal switch that is the problem OR the wiring. Keep in mind that the thermal switch will turn off the cold start valve when its too warm out, so if the valve floods things Id look at the switch (quick check with an ohmmeter). if unplugging the CSI when the engine is running makes a difference then your wiring is misconnected... the CSI cannot operate while the engine is running unless something is connected wrong. All FI wires are marked with their number near their ends, making things easy to trace out and check so long as noone has butchered things and cut them back. A consistant miss at idle on a specific cylinder is most likely eather a bad injector or its connector, OR a bad spark plug or its related wire. A bad injector however is more likely to cut your power down considerably over the whole range... and its also possible that a marginally lean idle mixture may be taking one cylinder out only at an idle if there is something marginal on that cylinder... swap in another pressure sensor if possible and see what you get. Keith Keith Park Top Notch Restorations topnotch@nycap.rr.com 71 Squareback (with no empty nipples!) 65 Notchback (still suckin its gas!) 65 Squareback 75 Opel 87 Golf 88 Rx7 10th Anniversary ----- Original Message ----- From: Christopher Sheridan <csheridan@virtual-consulting.net> To: <type3@vwtype3.org> Sent: Saturday, January 05, 2002 1:39 AM Subject: [T3] Fastback miss during idle update > 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 > > ------------------------------------------------------------------- > Too much? Digest! mailto:type3-d-request@vwtype3.org Subj=subscribe > > </x-charset>