I own a 92 cummins ext cab le with a518 tranny, turned fuel screw max, maxed out afc star-wheel, rotated fuel pin 90 degrees, and turned smoke screw till it does a lil black haze on start up. Why did my speedo stop working? And my overdrive isn't working anymore iv had it for 2 months and realized is stoped working right after my speedo quite on me?

 

is the speedo sensor hooked up to the side of your trans?

 

The od wont work without the speedometer. Check the connection at the vss on the driver side of the trans. Make sure the wiring is making a good connection and make sure the vss is hooked to the trans like sooty said. Fill out your signature when you get a chance so we can help you better in the future. Is the truck 2wd or 4wd? Kinda off topic but do you have gauges in the truck?

 

Ok will fill out. No gauges. Its my dd to school and work. Yes 4wd. Idk where th vss is? Could someone post pics so I could see?I'll check side of tranny to see if there's a bad connection.

 

There will be a sensor on the transfer case with two wires coming out that is the vss. There is also a square shaft inside the vss that can round out and then the speedo will not work. The fuel mods you have made to the pump are a VERY bad idea with out gauges.

 

Ok I will check the vss out. Thanks. So should I tune the fuel screw back to stock until I get gauges?

 

Yes you should turn the pump back to stock and then get gauges if you want to turn it back up.

 

When you were tweaking your pump is there any chance you unplugged the TPS ?
On my previous 2 1st gen auto's the TPS went bad and I lost O.D.
Just a thought.

 

Fixed it it was the vss with green n red wire on driver side of t-case. It was covered. Sprayed Electra clean and it fixed it right away. I have the dnr od fix kit.