Emmision and shaking

[sak]

I have 97 T100. Failed emmisions test on the 15mph HC test. However passed it on the 25mph test. So obviously its running rich do to higher than normal levels of HC (Hydro Carbons = unburnt fuel). Wondering if anyone has experience similar conditions and how they fixed it.

Secondly the steering wheels shake excessive at about 50-65mph. It is not brake related as it happens wihtout touching the brakes. However it only shakes in that range. Anything below or higher than those speeds tha shaking disappears.

Possibly problems?


btw, 97 T100 SR5 4WD package.

[YMCorolla]

Could it be the wheel bearings?

[trfytoy]

When was the last time you put a new catylitic converter on the truck?

Check tie rods and all steering components , ball joints, control arm bushings, for slop or wear.

[sak]

Originally Posted by trfytoy

When was the last time you put a new catylitic converter on the truck?

Check tie rods and all steering components , ball joints, control arm bushings, for slop or wear.

Sorry for the delay in response. I'm still getting use to the new forums as everyone can see, I'm new. I just assumed every post that I reply and thread that I made would be automatically subscribed. I was wrong. Any way I can make that change so its automatic???

Anyhow, as far as I know, the cat has never been changed. And talking to a smog technician, thats what it seems to most likely be considering the 25mph test was clean. He also suggested that the vehicle be to operating temps. But the truck was at test time. So the cat seems to be the only other option.

As for wheel bearings, to my knowledge will make a growling noise when it goes bad. Have done several wheel bearings before and they all gave the growling noise.

At the moment, no noise is heard so I will leave that out as a possibility at the moment. However, will check other suspension components for possible visuals.

Thanks for the heads up though.


BTW, does anyone happen to know what the cat looks like for the 97 T100 CA version? Looking online they all seem to exclude CA versions T100's and I don't know where the O2 sensors are on the truck. Truck not with me at the moment and won't be able to visually inspect it until this weekend.

[viper831]

The wheel shake could also be something as simple as an out of balance tire or possible a slightly bent rim.