88 D50 Carb backfiring

[Tech49]

Hey all. I have an 88 D50 2.6l M/T. I have been having trouble when the truck is cold. It doesn't have hardly any power and spits/sputters and hesitates and backfires up through the carb it sounds like. Once it warms up it runs fine. Any thoughts? Thanks

[camoit]

First question does it have the jet valve head?

Then welcome to the board. Be sure to explore all the nooks and cranny's of the site. We are always looking to make it better.

[Tech49]

Yeah it does have a jet valve head. I did put the jet valve eliminator kit in.

[camoit]

OK that rules out the sticking jet valve. You should put on a vacuum gage when it's cold and start it up to see if there is a valve sticking.
Also is the fuel filter new? If it's running lean it can cause issues.
If the EGR is stuck it will run rough but it should not back fire.



http://www.youtube.com/watch?v=vh3Z-F6KGkI

[Natureboy]

If it's running okay when warmed up it could be the choke not setting correctly when the engine's cold. Remove the air cleaner top, start it when the engine is cold, and watch the choke plate-you can also open it manually and see how it affects the idle. My need to adjust the choke.