The engine in my 88 runner runs really rough and the car shakes between 2.k and 3.3k, but at around 3.5k its like a turbo comes on and it just flies flies. So far i have changed these parts (all OEM), spark plugs, (NGK standard and iridium), spark plug wires, dist. cap and rotor (twice). The exhaust manifold was cracked so I changed that. It also had the valve adjusted and HG changed about 1k miles ago. The problem happens about 75% of the time. The other 25% of the time it runs beautifully. Before I though maybe it was related to rain or moisture, but it happens in all types of weather now. Can anyone give me any insight as to what might cause this problem?

 

is it a 22re or 22r? and have u looked over all the vacuum lines? sometimes theres holes u dont see until u remove and bend the hose around.

 

Well, its an '88 so definitely not a 22r (carb'd). '88 was the first year for the 3vze, so could be either the 22re or 3vze...

Was it happening before the valve adjustments and HG(s) replacement?

 

Sorry it's a 22RE, and yes it did happen before the valve adjustment and HG replacement.

 

Problem fixed! So far. a friend suggested that we replace the O2 Sensor, and it worked. The truck runs smoothly all over the rev range now. I'm still not sure if it was the O2 sensor that went bad, or something else caused the sensor to go bad. The sensor was non OEM AC Delco with 3 wires that was hooked up to the factory 4 wire set up. It looks really dirty. Not sure if its normal or not. I'll post pics later. Replaced it with OEM Denso from sparkplugs.com. Took me 5 mins and couldn't be happier. For now