MS2 v3.57 2.890 cut while warm-up

[q4_fre]

Hi all!

Installed yet an another ms2.
I have come across an problem.

Reluctor, 60-2, locked distributor - no movement.

Everything is working, accel enrichments needs some more work though, but as said, cold start..
When the engine is cold started, it is not possible to rev over ~3000rpm, the rpm dial in megatune just falls to 0, feels a bit like it isn't able to read rpm for a short moment. I can hold steady rpm under this, but when touching higher rpm or trying to rev it woun't do it, but it do not stop.
If you hold it at the problem zone, it stumbles and backfires, but not very much. Idle is no problem. When it leaves the warm up program, set to 60deg celcius now to speed up the time of the problem a little. As said, no problem when warm and out of the warm program.
If started partly warm, the same problem. The coolant sensor is now mounted in an position requiring some water circulation before it gets the right temp value. So sometimes it enters warm up program even when warm, then the same problem is apparent until the hot water hits the sensor and warm up is deactivated..

Also, if I connect the standard rpm gauge in the car to the - on the coil it has problems firing right at high rpm/load. Regardless of warm / cold.
What may this be?

Any ideas?

Fredrik.

[Matt Cramer]

Try putting a 10K resistor in line with the crankshaft position sensor wire and see if that improves things.

[q4_fre]

Thanks, sorry for the late answer but I will try it. The sensor winding resistance now is ~540 ohm. You want it in series with the sensor, right? On the ign cable, inner wire..?

[Matt Cramer]

That's correct, put it in series with the wire going to pin 24.