I've had my 94 ran 1500 5.9 for about 8 months now. GREAT truck with only an alternator changed besides a basic tune-up. But I'm having a big prob now. It started with slight missing after it warmed up but nothing major. I thought to change map sensor and while doing that, the check valve & vacuum hose snapped(dry rot) and so I did a quick hose fix until I find a complete fit. But now truck I is shaking badly after it warms up and only while giving gas. Maybe just air leak? Honest-I'm No mechanic. But I've had to drive like that for about a week because it's all I have so I'm asking, will changing check valve/vac hose fix it, or could I have done more damage?

 

What was the basic tune up? cap rotor plugs and wires? If so what plugs did you put in?

 

I'd suspect TPS or misfire(s). Even if no CEL. Check pending codes. Even if you just replaced plugs or wires, a single bad wire will cause severe bucking under load.

 

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I Put in good plus and wires. But I did that about 4 months ago. It really only shakes when it warms up and when I get to around 50-55mph.

 

That's misfires. Try unplugging the O2 sensor, and see if the problem goes away.

 

I haven't thought about TPS. would that be why it only does it around 50-55mph? Or could it still be only a wire?

 

That's more likely a misfire. You'll need to drive it and keep checking pending codes (if you don't get a hard code). It'll eventually tell you which cylinder is misbehaving

 

You mean plugs? What brand and type? 8mm wires?

 

I'll try that. Hey thanks everyone who reads these and helps out. Appreciate it. And I might b back on for help

 

You should post your resolution regardless. It may help the next guy like you.