Yukon Mystery

 

GM 5.3 Liter V8 EcoTec3 L83 Engine

The power steering on Jack's new GMC Yukon quit on him yesterday, so we opened the hood to see what we could see. Not much as you might expect, mostly acres of black plastic panels but there were a few openings where you could catch a glimpse of some metal things. Could not find the power steering pump or even the cap to the power steering reservoir. I mean you should at least be able to see the cap, how else are you going to check the fluid level? Hmm, maybe it doesn't have hydraulic power steering, it might very well have electric power steering.

But then I am looking at the belts. It has a serpentine belt that drives most all of the accessories like the air conditioning compressor, the alternator and the water pump, but then it also has a V-belt that is driving one pulley on the lower left of the engine. You can see it at the bottom center of the above picture. What the heck is that thing it's driving? It looks sort of like a pump, but there is no reservoir. The one hose fitting there connects to the vacuum line that goes to the power brake booster. Could it be a vacuum pump? That's just weird, man. 

Normally the power brake booster uses vacuum from the intake manifold, a design that has worked wonderfully for the last half century. Of course, that only works when the throttle is closed. It doesn't work so well when the throttle is wide open. But you wouldn't be stepping on the throttle at the same time as you are stepping on the brakes, would you? No, you wouldn't, but being as these new fangled cars are all drive-by-wire, you may not actually have control over the throttle anymore. The computer has control. 

I suspect this vacuum pump is there so you have a chance to win a fight with the computer should you ever have a disagreement over whether you should go faster or stop. That's kind of fucked up. They  replace the hydraulic power steering with an electric system to make the engine more fuel efficient, but then they add a vacuum pump to avoid a possible lawsuit the next time somebody dies in a fiery crash due to a stuck throttle, a throttle controlled by HAL, the evil master computer. Welcome to the modern world, and what a fucked up place it is.

As for Jack's problem, it went away the next time he started the car. There also appears to be a massive recall regarding this apparently common problem. No word on lawsuits about this issue have reached my desk, but that's not surprising what with all the worthless crap that has been flooding the internet this year.

P.S. The water pump has been moved away from it's traditional position on the front of the engine off to the side. I don't like it because it's different. Water pumps have always been mounted to the front of the engine. I suspect a commie plot. This might make it easier to change, except it won't because of all the other rigamarole you'll have to go through because of the electric-plastic bullshit you'll need to deal with.