Hello,

I have a 1989 ford ranger with a 2.9l v6. I want to know why my truck is burning lean, and do I need a new catalytic converter?

I rebuilt the engine on the truck and set the valves to 0 lash as I do not have feeler gauges. My neighbor (previous owner) says that it has a lot of blowby.
I want to know if the valves are out will it cause blowby to the point at which it causes my truck to burn. I was going to buy a new catalytic converter but I’m in California and catalytic converters that are carb compliant are extremely expensive.

Just to clarify, I want to know if the valves being out of adjustment would cause blowby, if blowby would cause the lean issue, and if that doesn’t do the trick how do I know I need a new cat.

 

How do you know its burning lean?

 

The smog man told me so.

 

I think you need more info than just that. is the CEL on? im not sure but I dont think new Cats will fix your problem. if you have a lot of blow by I would check the compression in the cylinders

 

No cel. I know the cylinders are low on compression do you the valves being way out of adjustment. I just wanna know if a lot of blowby will cause a lean burn?

 

if the valves were out of adjustment there would be a lot of ticking and clicking. im pretty sure they are hydraulic and non adjustable. if they were out of adjustment im not sure but I dont think that would cause a lean burning. have you replaced the O2 sensors?

 

The O2 sensor has been replaced there is some ticking in the motor and yes the valves are hydraulic and they are adjustable

 

my motor has 3 O2 sensors, 2 upstream and 1 after the Cat. the upstream sensors are the ones that control the motor fuel adjustments, as far as the valves you just tighten them down to a torque setting, 20ft lbs. here's something to look at

https://fordnews.org/how-to-adjust-v...ford-3-0l.html

 

What motor do you have? My truck only has one upstream 02 sensor (don’t forget the truck is a 1989). Also there is a specific gab to be measured when doing the valves, I mean this in the nicest way as texting gives off the wrong vibe, I think you might be a bit confused as to how they work on a 2.9l. The rockers have screws that you can tighten and loosen connected to the push rob to set the gap on the valve. Idk correct me if I’m wrong. 🤷‍♂️

 

ok, ive never worked on one that old. yes its different than the 3.0. I dont think I can help you any farther. there are people here that do know that motor well. maybe one jump in.

 

Ok thank you for you help, I do appreciate it.