Idle RPM increases when ALDL cable plugged in

[740turbo]

Hi guys I have owned my Sy for about a year now and have begun to search and read all the information i can on tuning. I currently have a laptop, aldl cable, tunerpro rt and some of the files ie .bin, xdf, ads. My first question is about idle rpm when I plug the aldl cable into the truck's data port. The truck idles at about 750 rpm normally, but when I insert the cable (without being plugged into the laptop and with it plugged in) the truck begins to idle around 1250- 1325 rpm. What causes this and will it effect anything when I am data logging and eventually tuning?

Thanks in advance,
Greg E

 

[MRKING]

Re: Idle RPM increases when ALDL cable plugged in

Is there a small switch on your aldl cable ? if so put it in the other position . some aldl cables have a circuit that places a resistor in line when the switch in in a certain position .obd1 cars send data differently and certain cables have a switch to select which one .

 

[JSM]

Re: Idle RPM increases when ALDL cable plugged in

Yes, your cable it putting ECM into ALDL mode.

 

[740turbo]

Re: Idle RPM increases when ALDL cable plugged in

Excellent that was the problem.

Would someone who has a good handle on Tunerpro rt PM me their number so I can get a good idea of how all the things I have read relate. I would love to just talk to someone because I feel like I am not doing something right.

Thanks,
Greg E

 

[akwilks]

Re: Idle RPM increases when ALDL cable plugged in

OMG!! You guys are awesome. This is the same condition I am dealing with. I thought I did something wrong when swapping out injectors but it could possibly be the aldl cable that I leave plugged in.......Yes!! I am now ready to begin with Code 59.......TYTILIDIE where are ya? I should have all my stuff including the wideband by the end of next month!!