jurq

ecu/ignition timing inputs? I'm having a slight issue of the car stumbling, rather bucking when under boost. When this happened, both times it was very warm, and I was stuck in bumper-to-bumper traffic. I could repeat the problem on command. Once I break free of traffic, full boost, zero bucking, full power. This after the engine compartment and coolant have declined significantly in temp due to airflow. In addition, I recently replaced the fuel distributor and have adjusted the CO2 mixture as best I can, but I have not been able to get my hands on a dwell meter to verify the setting-it just might be running a bit lean, leading to a knock condition, etc, etc.
No vacuum/boost leaks-car idles perfectly at 750 rpm.

TIA,
Jim

Kneale Brownson

Start at the link and scroll down for a bunch of information on the MFTS on Scott Mockry's wonderfully informative website.<ul><li><a href="http://www.sjmautotechnik.com/trouble_shooting/cooling.html#mfts_design">MFTS design</a></li></ul>

boxerfan

the quick check for the MFTS is to simply remove the connector and look for leaking coolant. Any sign of moisture and figure it is toast.

The Multi-Malfunction Temperature Sensor is what indicates the coolant temperature on the dash. It also indicated overheat conditions to the ECU. When the ECU sees wrong temps the fuel is always out of whack.

If you go lean the knock will back the timing to the retarded map. HTH.

aerohr

That is, if the knock sensors or MFTS or air temp or anything tell the ECU to turn it down, how does the car perform? Just a reduction in boost, or will there be other major changes?

boxerfan

- Second block of timing code.
- Limited boost
- different fueling...

It's designed to protect the engine because it is being abused if knock is sensed.