Forbito Posted April 18, 2014 Share Posted April 18, 2014 Hello everyone, I'm writing from Italy and I'm new in this forum, but I have already learned a lot here about Megasquirt. I bought a complete kit from Nigel (before I used Megajolt). The vehicle is a 1990 Land Rover 110 3.9, manual transmission. Yesterday I completed the wiring harness and I connected everything to try the first starting. The engine runs and all the readings are correct, except the manifold air temperature. The ECU reads -40° C, so the engine runs very rich to compensate the distorted value. This is the screen shown by Tunerstudio: The MAT sensor is a new AT1010, so it's not a problem of calibration. What may I do to solve the issue? Quote Link to comment Share on other sites More sharing options...
Forbito Posted April 18, 2014 Author Share Posted April 18, 2014 Okay, I opened this topic too soon, problem solved! Now I'm starting the tuning process, the engine runs very rich and with high tickover. As soon as I will ultimate the wiring loom (now it is still uncovered), I will post some pics of my installation Quote Link to comment Share on other sites More sharing options...
Hybrid_From_Hell Posted April 19, 2014 Share Posted April 19, 2014 And what had sir overlooked !??? Congrats for sorting Nige Quote Link to comment Share on other sites More sharing options...
Forbito Posted April 19, 2014 Author Share Posted April 19, 2014 A trivial stupid error in the wiring Now I have a perfect reading of the air temperature, but the coolant temp is a bit high (shows 21°C when it should be about 15°C). The next step is to gain a good tickover. Quote Link to comment Share on other sites More sharing options...
Hybrid_From_Hell Posted April 19, 2014 Share Posted April 19, 2014 Check here for threads on exactly this especially running pwm control !! Quote Link to comment Share on other sites More sharing options...
Forbito Posted April 22, 2014 Author Share Posted April 22, 2014 Quote Link to comment Share on other sites More sharing options...
Forbito Posted April 22, 2014 Author Share Posted April 22, 2014 Now I'm working on the VE table using an LC-2 wideband lambda. I had to lean quite a lot the map especially on the lower-left side of the table (I have been careful to proceed with the tuning phase only once the engine was warm and PWM plugged, without any TPS enrichement). Quote Link to comment Share on other sites More sharing options...
Hybrid_From_Hell Posted April 24, 2014 Share Posted April 24, 2014 Ah !!! PWM us powered closed - just unplugging it means it will remain open and let air in .... Quote Link to comment Share on other sites More sharing options...
Forbito Posted April 25, 2014 Author Share Posted April 25, 2014 Sorry badly written. I always cap the valve completely when tuning (the base idle si adjusted to 800rpm). Now the map is becoming to be quite good, but the PWM doesn't seem to work properly. In warmup mode the valve remains always fully open and in closed loop it varies the engine speed only when you edit a parameter (for example putting "800" instead of "850" in warm idle) and as soon as you touch the throttle the tickover returns high. I want to try to put a diode in the wiring to see what happens. Quote Link to comment Share on other sites More sharing options...
FridgeFreezer Posted April 25, 2014 Share Posted April 25, 2014 Some modes of idle control are simply ON/OFF for non-PWM valves, make sure you're in the correct mode. Also, if you have adjusted the base idle to 800rpm with the PWM completely blocked off, the PWM valve can never allow LESS air than this to help stabilise the idle, so it can never idle below 800 and it cannot close enough to drop the idle quickly, as your base idle is letting some air past. Quote Link to comment Share on other sites More sharing options...
Forbito Posted April 25, 2014 Author Share Posted April 25, 2014 ...if you have adjusted the base idle to 800rpm with the PWM completely blocked off, the PWM valve can never allow LESS air than this to help stabilise the idle, so it can never idle below 800 and it cannot close enough to drop the idle quickly, as your base idle is letting some air past. Clear, in fact I would like to obtain a stable warm idle of about 850 rpm. The problem is that the valve can not even mantein anything lower than 1300 rpm. However all the settings are fine. Quote Link to comment Share on other sites More sharing options...
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