TBI

[Kevin New Mexico]

I am new to this site. My truck is a 1990 C3500 with a 7.4 liter. Ignition modules have been a problem for the past two years. It was over the 100* mark yesterday when I got a load of hay. I stopped for a pop and the the truck would not start. I pulled the breather and the injectors were not emitting gas.up until yesterday a new Ignition modules has it going down the road, no dice. Towed it home. Today it fired right up. I let it get up to temp and shut it off, back to no spark. The pickup coil reads .2vac when cranking, it used to put out 1vac. Do you think that the output voltage is to low a cranking speed for the Ignition module to sense it. I have not read the output while cold. Any thoughts?
The truck is a daily driver at 60 miles a day. Also a heavy hauler I put 700 gallons of water in the bed. It is my work horse.

 

[Tzfbird]

I'm probably not much help but I had to put a new pickup coil in my C2500 because it was in pretty rough shape. I know you can replace just the coil for less than $20 and some time if you want to do it yourself. The ECM uses the pickup for firing the injectors so it sounds like you are on the right track and just need to decide on replacing the distributor or just the pickup.

 

[Kevin New Mexico]

Pick-up cool. Darn auto correct. Most times it helps me out.

 

[Kevin New Mexico]

Changed relay and started right up. I let it idle and 15 minutes later it died. No fuel pressure. I'll change the pump out.. chevy fun

 

[Kevin New Mexico]

Changed fuel pump. Good to go. I did change my base timing to 10*, I had been running 8* for the last 18 months.the list is 1 ignition module, 1 pick-up coil, 1 fuel pump relay. And last is a fuel pump
I am hoping with a new pick-up coil that it will stop going thru ignition modules. I like my dually.