Hello Scotty, I have a 91 Silverado and my engine light came on soon after I got a new cat. Since…

Guitarplayer10

Hello Scotty, I have a 91 Silverado and my engine light came on soon after I got a new cat. Since then my truck/engine has been shaking quite a bit and the idle would go up and down and be erratic. I changed my spark plugs and distributor cap and rotor and I still have the same problem. What do you suggest it may be? Oh and also every now and then when I shift into reverse or drive,Mainly reverse the truck would shut off but starts back up and takes off no problem, any ideas? Thank you for your time.

Comments (3)
No. 1-3
Guitarplayer10
Guitarplayer10

Would that*

Guitarplayer10
Guitarplayer10

OK thank you very much for the response, but that would apply to the truck shutting off or the erratic idle a d shaking?

ScottyKilmer
ScottyKilmer

Editor

sounds like you have more than one problem. But on those, as they age, fuel injection systems often begin to fail. Pressure test the fuel pump first and pray it's just that