Isn't that why they use a momentary switch?
When I did mine I only gave it a few quick taps on the switch, granted a PCM pulses it a lot quicker.
All mine on the Park Ave turned out ok, of course you do not want to give it constant voltage.
The guy did pulse his a bit much, and not fast enough, but as long as you do not keep the voltage on it is it really going to hurt it?
What cools them other than the fuel passing through?
Which the carb cleaner is the "fuel" when doing this.

PCM pulses the injectors on a millisecond scale, not seconds or minutes. Because they are only on briefly, they don't get hot enough internally to cause any kind of damage.

There is just enough fuel or cleaner going through to keep the injector cool during this normal intermittent duty cycle, unlike the constant cycle during the cleaning process which still allows sufficient heat to build up but not enough liquid is passing through.

Makes sense, it is risky and something one would do at their own risk.
It did not hurt mine on the Park Ave, and I flushed and reverse flushed, but I only did about 6-7 clicks each way, with cleaner spraying out every time, so the solenoid was never doing its thing without cleaner to cool it.
Never felt any warmth from the solenoid area, I know that plastic is a bit thick though.

Not saying it is the best way to clean an injector, but I have seen 3-4 DIY injector cleaning videos, and nobody ever mentions ruining their injector, not saying you can't, I totally believe it is possible if you are careless.

Only good option to clean them would be a shop that has the kit to do it, cheapest I have seen a decent kit for is 285.00 OTC 7649 Fuel Injector Cleaning Kit, the cleaner alone is 16.00
I think you can get a cleaner kit for like 170.00 still expensive.
But replacing all injectors if you burn them up is an expense wasted, so I totally get your point.

Lots of good information being gathered here!

So, now I have a question. How can a injector have LESS resistance after over 20 years of service? I could understand having more resistance due to wire being old, corrosion build up, etc.

Joel

That is a really good question.

It probably has shorted turns in the coil of the injector, not sure though I do not know injectors well, I am sure Mike or Tech II have a good idea..

It is possible that there were issues like a misfire in that cylinder in the past, and somebody got a different brand of injector, you'd expect it sill to have the same resistance, or within .5 ohms though.

Question, did you check the injectors while they were "hot", I read that you get more accurate results that way.

I did both tests on cold engine.

Joel

I decided to order the new AC Delco injectors #217307 and the o-ring kit #2173102 from Rockauto.

Appreciate all the comments and help
Joel

Some like to warm the motor for 15-20 minutes and then test, but it is not critical to do so..

Those AC Delco'* should be good to go for the remaining life of the car, I always recommend staying OE for all sensors, injectors, and any electronics for our GM vehicles.
I know some aftermarket brands do very well, but I have had issues with a few, so I'd rather stick to OE.

Let us know how it runs once you get the injectors in.

Oh yeah, sorry for not mentioning this sooner, you could have ordered one from RA, but since you are changing out all 6 you may want to consider changing the fuel filter.

ACDELCO GF578 {#25121293, 25121293NI} Professional is a good filter, but there are cheaper options.
That one is 11.32 on RA, they have a WIX 33311 that is around 9.00
It seems from RA most get this one for around 4.00 MAHLE/CLEVITE KL692
Or they get the AC Delco professional one.

OK Got the injectors and O-rings today. The injectors have o-rings installed already, and new retainer clips. I'll just send the 2173102 o-rings back.

It'll be another few days before I get time to install. Need to install the new fuel filter so that will be done.

I did check the resistance and they all read 12.4/12.3.

Joel

If it were me, I'd keep those o-rings.