1990 Cali ECU with Federal engine

[And_44]

Hello fellow DSM'rs,

I've been searching for hours and find limited results.

I have a stock 1990 Mitsubishi Eclipse GSX. The ECU in it is a Cali EPROM but when the previous owner swapped engines he put in a Federal engine with no EGR temp sensor so the CEL keeps getting hit up. I know where the sensor should be but this one doesn't have one. Right next to the Knock sensor on back of engine under intake manifold.

From what I can find in my search's is that because this is a 1990 that the adding the resistor to the board of the ECU won't fix the issue because of the programing installed on the Cali EPROM for the 1989 and 1990 models. They did something different with the 1991-1994's so this could work.

GOOD news is that the ECU has been socketed and rebuilt. So question is would finding a stock manual federal chip and installing it make it so the CEL won't appear? If this is done will the resistor still need to be installed on the board with the Fed chip? And would it matter if the chip is from a 1989/90 or 1991-1994?

And yes, I know switching to DSMlink that this can be taken care of. But figure the price of a stock chip compared to DSMlink is pretty HUGE difference. Car is still stock and rather spend the 400 bucks on maintenance first before an upgrade.

I have a unrepairable 1990 EPROM ECU floating around somewhere (from my previous Talon, owner didn't know why car wouldn't start and told me interior smelled of fish, turned out the ECU fried a nice hole at the caps) But if I can't find it anyone know where I could find a Federal chip or a reliable someone that could burn one? I'm pretty comfortable with installing the resistor myself if needed, just the chip has some pretty close prongs for me to remove myself.

Thank you for your time and any response's.

Drew

 

[92AWDHX40]

Send to ecmlink and have it fixed.

90 91 wiring different vfaq.com

 

[And_44]

I would if there was something wrong with it but theres not. Every thing is working the way it should it should just a configuration issue.

 

[Arthris]

there are two resistors on the board. I think with both of them out it goes to federal awd mode. On top of the eprom what does it say?

 

[And_44]

Id have to pull the ECU to see. But from my searchs the resistor fix does not work for 89/90 ECU's as the programming on the chip is what matters. I will probally end up attaching something to the plug in engine bay to fool the ecu into thinking its there. On top of that doing an emission delete and egr blockoff to clean up engine bay some. Also there is a leak in the vacuum lines for system so will just eliminate problem all together. When i get dsmlink for a christmas gift to myself it will be much easier.

 

[DSM1G90]

On the EGR temp sensor plug, put a 1/2 watt, 62K Ohm resistor in the plug, or trim the insulation off the wires to solder the resistor across the two wires. This fools the ECU that the Temp sensor is working if you don't want to fool with the ECU momboard to add the resistors in there to make the ECU a Federal ECU.

My 1.8 is a CALi ECU equipped Eclipse and the EGR temp sensor is bad causing a CEL. I did the resistor mod to turn off the CEL.

I did this mod trick when I got the car back in '02. Been working great since.

-DSM

 

[And_44]

Thank you very much dsm1g90. Ive been looking for something like that. I know its a temp sensor with resistence just didnt know the right resistor to use.

 

[DSM1G90]

Of course, I cheated: In the Chilton's manual in the "Emissions" chapter, in the EGR Temp sensor section (pg 4-15) is where it shows the values of resistance that the sensor reads at certain temperatures.

I happen to have this 62K resistor in store (even though one could have used up to a 83KOhm resistor) and figured that this was good enough to do the trick.

..and the ECU either reads voltage, or resistance from its sensors. Luckilly, this one uses resistance.

Good luck..and my pleasure always to help a fellow DSM owner out! - DSM