Chevy & GMC Vans

Hey all, so after the flurry of blower diagnoses a couple of weeks ago, I've got one of my own, but I'm not sure if it's the usual "resistor pack" issue, or something different:

I've got an issue with my blower fan going weak (or off altogether) under engine load. Weird, I know.

Typically happens most notably when climbing a long hill. I'll have my foot in it, trying to keep speed, and I'll notice that the fan just sort of... peters out. If I relax my right foot on the throttle, the fan comes back in. I don't notice any other electrical effects under load - like the radio doesn't go funny or any other obvious electrical deficiency. The dashboard voltmeter looks fine when this happens, but I've switched one of my ScanGauge monitors to voltage so I can get a more accurate reading when next it happens.

I've got a replacement resistor pack sitting in the box, but I don't want to take the "start replacing parts until the problem is fixed" approach if I can avoid it.

Does this sound familiar to anyone else?

Check/replace the vacuum tubing to the vacuum tank ball near right front fender. Also check the vacuum line that runs across the engine compartment.

There's a sticky thread in 'climate control' section on other site.

1st thought: Sweet!

<Reads procedure>

2nd thought: Uuuuugh.

Thanks, Stoverlander. Doubt I'll be able to get that sorted before my road trip, but oh, well.

It's actually really easy to replace that tubing and you can pickup the molded vacuum tube piece at most laps.

Not sure if you read this thread: https://www.astrosafari.com/viewtopic.php?f=34&t=4468

Stroverlander wrote:It's actually really easy to replace that tubing and you can pickup the molded vacuum tube piece at most laps.

Not sure if you read this thread: https://www.astrosafari.com/viewtopic.php?f=34&t=4468

Yep, I read it. I was only bitching because I'm short, with short arms, and a lifted van, so I might need scaffolding to reach the nipple on the engine block area!

Probably time to get my daughter to help. I was a bit younger than her when my Dad would have me adjust the valves on the Triumph by holding me over the engine...

I hear that, it can be a pain to get in there with a lifted van!