Strange clicking from passenger side dash area

[HoeLV]

Actuator or possibly pine needles in the blower fan.

This caught my eye.

I have a 98 Tahoe (2 door, 4WD) and am hearing this same ticking noise under the passenger side dash. Ever since I bought the truck, I have been pulling pine needles from every crevice. U was having issues with water dripping down by the blower motor and got that sealed and no more issues there. I'm sure pine needles would have made their way down as well.

Can you go a little more into where to look for the pine needles in the blower?

Thanks

 

[someotherguy]

Once you pull the blower motor out, any pine needles and debris in that circular portion of the housing will be readily seen and removed.

The ticking noise OP is describing is generally much louder than any pine needles could produce and is coming from a faulty actuator.

Richard

 

[HoeLV]

Once you pull the blower motor out, any pine needles and debris in that circular portion of the housing will be readily seen and removed.

The ticking noise OP is describing is generally much louder than any pine needles could produce and is coming from a faulty actuator.

Richard

i havent had a chance to look under there much. a couple months ago i changed the blower motor resistor and i pulled the blower motor itself and cleared out the box it sits in the best i could at the time. i was unaware of the closeness of the actuator/door and it all being interconnected at the time.

a couple days ago i took a quick look and verified the noise was coming from the actuator behind the glovebox, i could see/hear it trying to move the door. however, when i reached under, i could feel the door it was trying to move appeared to be closed. i could push it open a little and once i let go, it would again close and the actuator would continue to run.

i was wondering if perhaps there was something blocking it (ie pine needles) from completely closing and that was causing it to continue to run.

if i press the recirc button, nothing appears to change.

i guess i am a bit confused as to if it is broken or not. i would understand when turning the recirc on and hearing the actuator run continuously trying to open the door, but when turning the recirc off, i would guess that the actuator would stop trying to do anything as the door is already closed. it almost seems like an electrical issue and for some reason it is constantly getting power/signal telling it to do something (or is this the symptom of a bad actuator?)

 

[highwaystar]

Your actuator has plastic gears in it. They are broken & it is the recirculation actuator.

 

[OLD BLUE 88]

Last year I rebuilt my HVAC system on my 88 truck. It has the old control unit WITHOUT a MAX AC button. Local shop sold me a Dorman actuator that worked for a few months. I got it to work by grounding the second wire coming out of the high pressure sensor on the back of the compressor. Then it stopped. Now, after some research w Dorman, they stated they do not manufacture a fresh air inlet (recirculate) door actuator for that vintage. Why this one worked for awhile, who knows. Called GM, they said they could not find one anywhere in the country for that era truck. Before I play hit or miss, can anyone give me some direction as to where I can obtain one of these?

I rummaged through the old actuators and MAY have the original recirc (it didn't work for a long time, but may have been due to not getting a signal). IF the actuator I have in hand is the air inlet unit, it has six pins and spins freely when the first two are connected to a 9V battery. From what I understand, the original actuator only has two or three pins, so maybe the ones I have in hand are the wrong type. My assumption is that it goes into recirc when it senses high pressure off the compressor in that it would open to fresh air once the AC was set to low fan or not to coldest setting.

For now, the system is charged and blowing cool, with the recirc door locked in recirc mode with bailing wire to hold back the Texas summer heat, but it would be nice to have the old truck working properly.

Thanks for your time and interest.

If all else fails, I may rig up a cable to manually change it to fresh air as needed.

 

[FrankieD61]

Hey guys.

I wanted to post this just so if anyone else has this issue, they might have a good chance of fixing this issue.

So, for the original issue of the clicking: That was fixed by taking the recirc blend door actuator apart, reflowing all of the solder joints, and giving everything a good spray down of white lithium grease. Replacement of this component would suffice, too. No more clicking.

Now, another issue I had was the "mode cursor" on the control head was blinking any time I would go from key-off to key-on or if the temp change bar was pressed. I fixed this by removing my radio (made easy by the previous owner and his "pro" install), removing the temp actuator, and doing the same thing I did with the recirc actuator. A replacement of this component would have been sufficient here as well.

Hope this helps someone. Sorry for the long-windedness.

 

[someotherguy]

Some have actually found cracked or broken gears in their bad actuators. It's good to hear re-soldering fixed some of yours. As the years keep ticking by, we'll find more and more electronic parts in these trucks that can be revived with a simple re-solder, as the solder joints fail over time. First the wiper motors, then the cruise modules, now the HVAC actuators join the list...

Richard

 

[OLD BLUE 88]

I dug up the old recirc actuator (assumption, no part number), took it apart, lubed and tested it w battery. Works. Will tinker w a series connection from HP to LP sensors to see if that gets a signal to the actuator. Any instruction will be appreciated.

Still can't figure why Dorman unit worked when Dorman stated it was the wrong unit.

May try another control head

 

[Aviazx]

This caught my eye.

I have a 98 Tahoe (2 door, 4WD) and am hearing this same ticking noise under the passenger side dash. Ever since I bought the truck, I have been pulling pine needles from every crevice. U was having issues with water dripping down by the blower motor and got that sealed and no more issues there. I'm sure pine needles would have made their way down as well.

Can you go a little more into where to look for the pine needles in the blower?

Thanks

Where did you seal the water leak? Was it coming from under the plastic cowl cover beneath the wiper blades