Diving into the dash ('98 Tahoe)- asking for suggestions...

[Allen_B]

I am in the planning stage for pulling the dash apart on our '98 Tahoe. The dash in in great shape but have really poor airflow and have to assume the AC evap is plugged up. Also, the AC is non-op but not sure what the issue is- I suspect the AC evap is a likely culprit for my freon leak but haven't loaded the system with dye to check. I'll tackle the AC problem soon and have a feeling it will get to be a royal pain but the evap looks to he the biggest pain.

My questions are what would be smart to check/replace while I have the dash apart? My thought was on a 16+ year old vehicle since I am pulling the crap apart and don't want to do it a second (or third) time, I was thinking:

- Replace the AC evap
- Replace the heater core
- Clean and inspect the firewall and behind the dash

What other items are common failure items that require the dash to be pulled? Don't want to send the wrong signal, I'm not throwing money away by replacing a bunch of stuff for the hell of it I just would rather hit the usual suspects when everything is pulled apart.

Another issue I have noticed but not sure if it is dash related it the fuel gauge and oil pressure gauge both "buzz" and by that I mean the look to vibrate. They indicate and track but they should not buzz like they do and not sure if this is a loose connection somewhere that I could address while I am taking stuff apart...

Thanks!

Allen

 

[east302]

You can clean off the blower side of the evaporator coil without removing the dash. Here's a how-to in case you haven't seen it yet...

http://www.gmt400.com/forum/showthread.php?16610-Improve-obs-A-C&

Cleaning off the crud in there will probably help your airflow issue. Using a self-rinsing coil cleaner works pretty well.

I'd see where that leak is first, it may be something simple.


Sent from my iPhone using Tapatalk

 

[Allen_B]

I have seen the tutorials on cleaning out the evap coil but that is really the purpose of the question- Should I go ahead and replace it and the heater core?

Asking since I am not sure how often they fail, especially after this long...

/r

Allen

 

[BigKahuna]

Buzzing or vibration in the gauges is the stepper motors getting reafy to fail... You can 1. Replace entire cluster 2. Send cluster out for repair. 3. Self repair the cluster if your decent with a soldering iron. The steppers are easy to get online, and the repair is fairly simple... Do them all while you have it apart tho..

 

[east302]

Buzzing or vibration in the gauges is the stepper motors getting reafy to fail... You can 1. Replace entire cluster 2. Send cluster out for repair. 3. Self repair the cluster if your decent with a soldering iron. The steppers are easy to get online, and the repair is fairly simple... Do them all while you have it apart tho..

Are the stepper motors filled with an oil or something? Some of my gauges have a sheen under the needle post that looks like something leaked.

 

[BigKahuna]

I would gueas that the motors would have some type of lubricant within them. Sounds like this may be leaking out? I think it cost me 2 hrs and 50 bucks to do all the ones in my gmt800, and about the same for the gmt400 i did for my pops..

 

[badbadleroybrown]

A common problem are the seals around the doors for the defrost and air conditioning literally melting away. When I go into my dash I will replace them with this: Heater-Air Distributor 52467204