View Full Version : Car Idling Bad

07-24-2003, 01:56 PM
I have an 87 Mustang with a new crate motor with 2000 miles on it. The car was built when I bought it. It has an MSD6AL ignition and pro-billet 8456 distributor as well as a Blaster TFI coil. The car ran fine when I first got it. One day a few weeks ago I went out and it wouldnt start. I was not getting any spark. I took the ignition module to a local speed shop in Cincinnati. They have the MSD display and they tested my box and it wasnt firing at all. They shop has units there that are rebuilt, so they took mine as a trade in and made me a good deal on the rebuilt one. I took it home and installed it. Now the car sounds like it has s slight miss in it around 2000 rpm's when you just hit the throttle. When the is cold it will run fine but after warming up it wont idle. If I dont give it gas it will die. Is there anything in the MSD setup that may be causing this? I alos noticed that when I swapped the unit out, that the person who did the initial install hooked the red + wire from the box to another wire that then went to the positive side of the starter solenoid. The wire that it is spliced to runs the fan. Will this effect performance?

07-24-2003, 03:12 PM
If it is the heavy red wire that is tied into the wire of the starter solenoid and the fan, this can affect the performance of the unit. It is recommended to go directly to the battery positive, because the battery is a capacitor and can filter any noise generated by the fan.