e36 megasquirt

[trofa]

hi,

i am trying to run megasquirt 1 extra on my 323Ti, OBDII, with the MS41.0, first i want to control only the fuel, and once everything is ok, control the spark. so i have the original ecu controling the ignition and de megasquirt controling the fuel.

the problem: the engine overheats, before the megasquirt i never had eany overheating problem, but now the engine temp goes up and i have to turn of the engine.

facts:the enfine is not runing lean, in fact, i am running it really rich to be sure this is not the cause. (11-12:1 AFR)
ambient temperatur arrount 20-28C (dont know how meany farenheit)
intake temp (30-40c)
engine is a M52B25 with exhoust,CAI and M50 intake
engine worked perfectly fine before megasquirt, so is nothing mechanicaly linked problem.

what i thought it might be is that the stock ecu gets to some sort of ''limp mode'' and retards timing, thus, incresing the temperature.

sorry for my english, is not my native language.

[808e36]

Any injector error codes from the dme? Are you using resistors to simulate injector coil impedance to the stock dme?

[CMG]

Coolant system is kinda seperate from dme. Water pump circulates and thermostat opens. Running ms might cause temps to rise due to the tunung but shouldn't cause overheat.

[trofa]

i am not simulating any resistance to the DME, you say that if i simulate the injetor resistance to the dme, this will make it to go back and work OK?

the cooling system is totaly separete system, but if the timming is too retarded or running really lean AFR, the engine temp rises.

also i thought tha something with the knock sensors might be going on, since it sesnses noise from the normal combustion but it does not sense any injetor activity.

thankss for you help

also the dme does not have signal from Coolant sensor, intake air sensor and TPS.

[trofa]

no one?

[det1990]

are you saying that the temp gauge goes all the way to hot as soon as you turn it on
or after running for a bit if it happens as soon as you turn it on check coolant temp sensor

[trofa]

the temperature gauge from the dash board and the one from megatune, both slowly go up after i turn on the car, it takes arroun 4-5 minutes to get to normal running temperature, and after 3 or 4 minutes more the engine stars to overheat. goes up and does not stop unless i turn off the engine,

[redline61]

I know this may be a dumb question but is it a mechanical or electric fan? Is it turning on for sure?

[trofa]

mechanical fan, its workning, also tried driving at 50mph and still overheats

[trofa]

mechanical fan, its workning, also tried driving at 50mph and still overheats

[m20powered]

If the stock ECU still has O2 sensor(s) hooked up maybe it doesn't like what it is seeing and assumes that there is a problem. Especially if you are running it rich with MS. Not sure how the stock ECU would behave in this case, maybe it is retarding the timing like you suspect.

[redline61]

I really think you would be best off going all in on the megasquirt. I frankly am surprised it runs with one ecu controlling the fuel, and one controlling the ignition. Would it be possible to log what the ignition is doing with timing? Could you run an input into mega that shows what the factory ecu is doing with timing?
I can't imagine what the stock computer is thinking when it sees the engine is running without any fuel inputs.

Also kind of a weird long shot but does the engine have a electronic thermostat? My E46 had one and could be unplugged but I have no idea about the E36 engines.

[trofa]

have tried disconectin all the o2 sensors and the same happends, i dont know if the e36 haves an electric thermostat, i think that the best way to go os full megasquirt and solve any problem from there on

[328iFun]

This should be a totally separate issue from the "squirt".

You need to take a good luck at your cooling system. Its either your fan, water pump or thermostat.