Quick AHC question - pump, globes or ??? (1 Viewer)

[James Bentley]

My 2004 LX is not my daily driver, it sits on a charger most days and gets driven every 1-2 weeks or on weekends.

Within a few seconds of starting, the AHC pump runs a short while and it raises a bit and levels out to its normal height.

Question: Is this indicative of the globes going out, normal or something else?

One other possibly related oddity is that the truck will feel like it sinks or drops in the front end and by the time I think "what was that?"...I can see the hood raising up a bit and it confirms what my seat of the pants felt. I most notice this at a stop light, stop-n-go traffic or after having driven a bit and then coming to a stop.

Anyone experienced that too?

I have flushed the AHC and have good pressures thanks to @PADDO and this post: Props to PADDO's AHC fluid replacement method!

 

[LXKevin]

Sounds like normal system adjustments. If you have techstream you could post a pic from the data list for evaluation. What do you get when you do the graduation test?

 

[suprarx7nut]

Hard to say if that's normal. I never noticed active height adjustments while driving.

If you have a leak in the system, you might lose height occasionally. Check for leaks and hook up Techstream.

 

[DanInDenver]

Maybe leave it in low when you your not driving it for extended periods.
May also be a height sensor going bad? Mine did what you described shortly before one of my sensors failed.
Remove and inspect them, clean as needed.

 

[jahawk]

Mine occasionally does they same. I figured it's just a quirk of the system.

Jim

 

[ramangain]

What are your sensor height readings?

 

[James Bentley]

Sounds like normal system adjustments. If you have techstream you could post a pic from the data list for evaluation. What do you get when you do the graduation test?

@ramangain here's a pic and let me check my notes for prior graduations (no visible leaks)

 

[James Bentley]

Sounds like normal system adjustments. If you have techstream you could post a pic from the data list for evaluation. What do you get when you do the graduation test?

I get 10 graduations between L and H

 

[James Bentley]

Maybe leave it in low when you your not driving it for extended periods.
May also be a height sensor going bad? Mine did what you described shortly before one of my sensors failed.
Remove and inspect them, clean as needed.

Hi @DanInDenver were you able to test or see in Techstream the faulty sensor? This rig was originally a mall crawler from Phoenix with extensive service/maintenance history at the dealership = no mud or rocks, yet!

 

[ramangain]

Adjust those front height sensors so they are both closer to nominal

 

[LXKevin]

I get 10 graduations between L and H

Considering you're running sliders, fridge, and solar (extra weight) your data Looks pretty good. Inspect and adjust the front sensors as @ramangain instructs. Graduations are good. It's an "Active" Height Control system as such it's constantly adjusting whether we feel it or not. When you are trying to get everything in spec have the truck on a level surface with a full tank of fuel.

 

[James Bentley]

Considering you're running sliders, fridge, and solar (extra weight) your data Looks pretty good. Inspect and adjust the front sensors as @ramangain instructs. Graduations are good. It's an "Active" Height Control system as such it's constantly adjusting whether we feel it or not. When you are trying to get everything in spec have the truck on a level surface with a full tank of fuel.

Will do and thank you all!