MS3 Goldbox help?

James408

Member
May 18, 2020
25
5
13
New York
Let me just start by saying I did check and it is a good oem ford iac for 1986 mustang. It was operating properly on the old a9l ecu but it does have that inline resistor right before the plug to the iac. So unless that resistor is effecting it I dont know why the ms3 goldbox isnt really communicating with it? I can get the car to start run and idle pretty smooth once it settles but im working out another issue. Reading like 75 to 80 degrees after idling for a long time like 30 plus minutes and car is very very warm like up to or above full operating temp. So I think sensor maybe bad or something skewing reading there causing rich running condition fooling ecu into thinking cars colder than it is... Car info is has a aem 30-4110 wideband calibrated to ecu. Tps is working and calibrated to ecu. Timing locked to distributor timing matched together when ecu in locked Timing. Afrs generally very rich around 11 to 12 flucuating alot at idle and under very light throttle drive around the block was like 10 to 12 afrs some 13s but very light throttle and low rpms. So im assuming the ecu seeing cold temps like 75 degrees from sensor is the rich running issue right now?
 
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Have you done any tuning on the main VE table? the base tune is just there to get you started, its up to you to get the AFR dialed in.
I was starting on the main ve table and got the idle very smooth with no surging at all right around 850rpms. A bit on the rich side like an 12 to 13 afr at idle but sound really good. I tried taking it for a very short ride (barely a mile) to get gas. Stayed low rpms very light throttle. Afrs where ok in low roms but once I started working into anything above 2500 rpms I'm seeing 11.5 even 10 afr so very rich. I'm assuming thats because of the ect sensor telling ecu its like 75 degrees fully warm. I checked with a infrared thermometer on the crossover tube where sensor is and reading 180 to 190 degress fully warm so maybe sensor is going bad and cant read higher temp ranges. Every time i try to lean out my ve table cells afrs slowly fall rich again I'm thinking possibly from the temperature sensor issue? I tried to sweep the iac valve with locked timing and engine rpm did not change so maybe my settings are wrong for the idle control circuit?
 
Ah ok I was not understanding, yes the wrong information from the ECT will keep warmup enrichment active. your thoughts are correct
Ok so ect will be my first priority then. Thank you for helping clarify that I'm pretty lost with alot of this being so new to it lol. Now just got to figure out why I cant sweep the idle air control valve seems like ms3 goldbox having trouble communicating with it. If its not the settings as I tried all different frequencies and normal and inverted settings still cant sweep it I should probably make sure the thing is still good first. Next nice day going to test it with a dmm