no ecu communication

[4130]

Ok let me start by saying that I have no communication in my ecu in my 92 mitsubishi eclipse gs-t. I got a brand new datalogger but It will not connect. My question is do I have a burnt up ecu or a bad connection? I also have a very crappy idle it idles like if it has cams. Now my car use to idle alot better but it all started after I swaped out my upper intercooler piping for a hard 2.5 pipe, and a non turbo throttle body. I though my idle was caused by a boost leak but even after I fix them it still didnt seem to idle a hole lot better. Now this is the reason why I think I could have a bad ecu. When I was installing my upper intercooler pipe I forgot to disconnect my battery so I accidentaly grounded my positive side of my battery with my intercooler pipe that was touching my transmission. It spark for second could that cause my ecu to go bye bye? I also tried pulling a check engine code with a code scanner but it still could not connect to my ecu? So I try to put in another ecu still cannot connect and then I checked all my fuses still cannot connect. Is there a way to check if I have a shorted wire or a loose connetion at my diagnosctic port going to my ecu?? I have another ecu but im scared that if I connect this one it my burnt it up due to a possibly shorted wire. I would appreciate any ideas, answers or questions I really need to fix this problem so I can finnaly tune my car. So please can anyone help me!!!

 

[xioca]

Check out your data cable in a buddies car.

 

[Mrdrd_Laser]

Do you have a datalogger cable with the spade connectors or the factory plug? You may have the connectors on the wrong pins

 

[4130]

My datalogger has the factory plug conector. Could I have a bad ground on my diagnostic port? and If so does anyone had the diagnostic port pinout to check wich pinounts have grouds or powers. And I havent tried my datalogger cable in any of my friends cars because they all have 2g's.

 

[steve]

You must be logged in to view this image or video.

Is your car idling on two cylinders?
Is the Check Engine Light on?

You haven't provided any detail on the datalogger other than it has a real ALDL connector, how is it connecting to the logger and what logger?

The short via the UICP to the transmission shouldn't have blown any fuses. It shouldn't have caused any other issues either unless you were grounding the pipe to other things as well while it was touching the positive terminal.

Have you inspected your ECU for leaking caps or other damage?

 

[4130]

im using a palm m105 with pokectloggers sofware and Im using a male to female serial port wich connects the aldl connector to the palm m105. My car runs fine other than the bad idle and I currently have no check engine light on. I did check my ecu and my eprom did have minor leaking caps but my non eprom looked in really good shape. I do have another non eprom ecu in good shape so you guys think it would be a good idea to put that one in a see if works?

 

[steve]

im using a palm m105 with pokectloggers sofware and Im using a male to female serial port wich connects the aldl connector to the palm m105.

The logger cable should connect directly to the Palm hotsync cable. That means the logger cable for a Palm device should have a male DB9 that connects to the female DB9 on the Palm hotsync cable. If you have to use some sort of gender changer you also need a null modem adapter that swaps pins 2 and 3 on the RS-232 interface.

 

[brownfinger]

If you have to use some sort of gender changer you also need a null modem adapter that swaps pins 2 and 3 on the RS-232 interface.

That drove me crazy when I tried hooking up to a laptop with my palm cable. The null-modem and serial plugs are 100% identical, they just use different pins. It sounds like you have a cable built for use with a laptop. $5 for the adapter at any computer-geek shop. They won't have it at Best Buy.

 

[4130]

I believe I have the right connection. My logger cable has a male serial port wich connects to a female serial port hotsynch ccable to my palm. If my datalogger is not the problem then Im hoping is pin 12 ground that is bad. If I dont have no ground on pin 12 were does pin 12 ground to so I can check the connection??

 

[steve]

If my datalogger is not the problem then Im hoping is pin 12 ground that is bad. If I dont have no ground on pin 12 were does pin 12 ground to so I can check the connection??

The FSM says that the diagnostic port pin 12 runs to the #8 ground which is the one on the drivers side kickpanel.