After the CFI -> MPI Conversion - Ford Forums - Mustang Forum, Ford Trucks, Ford Focus and Ford Cars

NZ · 07-24-2002, 15:51

Well I have converted the CFI to MPI and the car goes sweet. It went even sweeter after I set the timing (it was 10 degrees retarded). It went even better after I changed the fuel filter, way way more responsive. It will now break loose in 1st gear and 2nd if its wet. I did not change the Dizzy, what ever it is.
One thing I can not work out though is the idle. I cannot get any power to the idle speed control valve. I even probed the pin (i think it was 21 or 41) on the ecu and couldnt get any power from it. I tried with the car running and key on engine off. The ecu was from a 4.0l multipoint, I don't know what E series it was though. It was also a automatic. I am 5 speed
At the moment I have the idle screw turned way up to get it to idle.

Any ideas? Maybe if I tried a different ecu?

ANyway if anyone wants info on the conversion, feel free to email me.

karlth@bigpond,.com

Brent79 · 07-24-2002, 19:20

Hmmm... i wouldnt have thought the 4.0L version ecu would work properly. Did you use the loom from an EB2 4L engine? maybe the pinouts changed slightly from the 3.9L? I myself couldnt find the ISC pulse signal. I had to use the purge valve line to the ECU and even tho the wiring diagrams i used suggested this wouldnt work, it does. When set up the way the diagram shows, it wouldnt idle.

Brent

Aussiblue · 07-25-2002, 07:24

If the engines not hot you are looking for a voltage that's not meant to be there. The ECU provides a 160 hertz aquare wave with a varying duty cycle to this valve. Try measuring current instead. 1 Amp = Max bypass, zero = minimum bypass. You should however find a 9 to 10 volt pulse when the engine is HOT and ideling though. Also try unplugging it when its ideling and hot; the engine speed should noticabley change. Turn the headlights (highbeam), air con etc on to put the engine under load and the voltage at the ISC should increase.

The wiring is different between CFI and MPEFI. On the latter one wire goes to the TFI module the other to the ECU. On the CFI they have four wires running back to the ECI.