Optimax throttle plate 1.5l

[Motv18]

So I think I goofed lucky I marked it befor moving anything. Unlike the 3.0l with the solid rods the 1.5l has a cable that’s adjustable. Port side has a dab of wax but starboard doesn’t.

Doing my precheck checking plugs air gap on crank sensor ect and all that stuff I noticed the cables were super slack and tightened it up. ...oops I set it back to the marks after re reading the book about it being factory calibration for the speed density stuff. This also messed with tps readings.

My book doesn’t have any spec or set up on the throttle body. It currently matches the full throttle reverse voltage on the tps 3.7v. I caught it before messing with the other cable.

As as long as the maps good I don’t think it will affect much just run odd.

Any help setting it back correctly would be appreciated.

[Motv18]

I was able to get ahold of section 7a throttle cable replacement portion of the service manual 90-889785r01 November 2007 for the cables the go over the engine from port to starboard. Or from the lever to the throttle plate cam lever and roller to open the throttle body.

The throttle body side threads reads on the cable should be set to 14.71mm +-1.1mm (.58+-.04”) for idle and wot (wot is the outside) lower nut tighten to 65inlb

on the port side pull the casing to remove slack top nut finger tight against bracket lower nut tighten to 65inlb.

Not super tight but no slack. And working against each other. To much slack can delay opening the throttle plate and lean you out off idle and delay throttle pickup or excessive forward tracer in the remote befor power comes on. I never lean nocked just a caution. If slack enough it can reduce wot power if it is closed up more then the restriction ring air flow.

Positioning of the throttle plate opening is controlled by the throttle stop on the port side. And measuring the stand off from a set screw and stop on the throttle body. It’s tough to get to with the tank on but possible. And probably won’t need adjusting but for a check set it wot and stick a feeler gauge in for .02-.04 inch (.508-1.016mm). Amolst need to see the picture for where to measure.

On the 1.5l 75,90,115 the high idle chug / going on plane slow chug miss feel is one of the more common issues.

The plate does come full open and the restrictions are the power adjusters with computer stuff and other things.

Hope some others are helped by this.

For or me I had my flow meter drop from 8.2 gph to 7.0 gph. I thought it was a prop change but found the cables loose when doing a check and it didn’t seem right.