AHC help

[SaadUK]

Hi guys. I have a 2003 LC Amazon Diesel. It comes with AHC suspension. The problem is even after changing the following parts, the ride quality is harsh and too much cabin noise. I have bleed it a couple of times to make sure there is no air in the system but still no gain. I actually have another Amazon which is 2002 and its ride is silk as butter. I have changed the below mentioned items on that as well. Id be grateful if someone can guide me as I have spend a terrible amount of money and it looks like it went down the drain.

Thank you.



PUMP & MOTOR ASSY, HEIGHT CONTROL
ACCUMULATOR, FRONT SUSPENSION CONTROL
ACCUMULATOR, REAR SUSPENSION CONTROL
ACCUMULATOR ASSY, SUSPENSION CONTROL PUMP
SHOCK, REAR RH W(ACTIVE HEIGHT CONTROL)
SHOCK, REAR LH W(ACTIVE HEIGHT CONTROL)
SPRING, COIL, REAR RH W(ACTIVE HEIGHT CONTROL)
SPRING, COIL, REAR LH W(ACTIVE HEIGHT CONTROL)
ABSORBER ASSY, SHOCK, FRONT RH (ACTIVE HEIGHT CONTROL)
ABSORBER ASSY, SHOCK, FRONT LH (ACTIVE HEIGHT CONTROL)
ACCUMULATOR ASSY, FRONT SUSPENSION CONTROL, RH
ACCUMULATOR ASSY, FRONT SUSPENSION CONTROL, LH
ACCUMULATOR ASSY, REAR SUSPENSION CONTROL, RH
ACCUMULATOR ASSY, REAR SUSPENSION CONTROL, LH

 

[agaisin]

Hi guys. I have a 2003 LC Amazon Diesel. It comes with AHC suspension. The problem is even after changing the following parts, the ride quality is harsh and too much cabin noise. I have bleed it a couple of times to make sure there is no air in the system but still no gain. I actually have another Amazon which is 2002 and its ride is silk as butter. I have changed the below mentioned items on that as well. Id be grateful if someone can guide me as I have spend a terrible amount of money and it looks like it went down the drain.

Thank you.

PUMP & MOTOR ASSY, HEIGHT CONTROL
ACCUMULATOR, FRONT SUSPENSION CONTROL
ACCUMULATOR, REAR SUSPENSION CONTROL
ACCUMULATOR ASSY, SUSPENSION CONTROL PUMP
SHOCK, REAR RH W(ACTIVE HEIGHT CONTROL)
SHOCK, REAR LH W(ACTIVE HEIGHT CONTROL)
SPRING, COIL, REAR RH W(ACTIVE HEIGHT CONTROL)
SPRING, COIL, REAR LH W(ACTIVE HEIGHT CONTROL)
ABSORBER ASSY, SHOCK, FRONT RH (ACTIVE HEIGHT CONTROL)
ABSORBER ASSY, SHOCK, FRONT LH (ACTIVE HEIGHT CONTROL)
ACCUMULATOR ASSY, FRONT SUSPENSION CONTROL, RH
ACCUMULATOR ASSY, FRONT SUSPENSION CONTROL, LH
ACCUMULATOR ASSY, REAR SUSPENSION CONTROL, RH
ACCUMULATOR ASSY, REAR SUSPENSION CONTROL, LH

I'm afraid to do the math on all those parts. ouch! did you replace the parts on your own?

what led you to replace all those pricey parts, sorry to be blunt but it seems like you weren't sure what the issue was to begin with?

without any more details on your situation i'd suggest some basics first:
- check that your ride height front and rear is to spec per fsm
- check for ahc related dtc codes (obd will not show you these)
- and probably most importantly check your neutral pressure!!!! you can have perfectly functioning parts with sky high neutral pressure which will give you harsh ride despite good parts etc...
- also is your damping switch working?
- while probably unlikely it's possible that your new globes failed either due to defect, contaminated fluid etc. It's also possible one of your other parts failed. it's also possible height control ecu or something else you didnt replace is faulty... i would start with all the checks above but for testing globes you can do the reservoir gradations test, for any electronics dtcs would probably show, and there are diagnostic tests you can do with techstream software (or without) as documented in the fsm to check most of the electronic parts etc...

btw, can i get your old parts?...

 

[SaadUK]

I'm afraid to do the math on all those parts. ouch! did you replace the parts on your own?

what led you to replace all those pricey parts, sorry to be blunt but it seems like you weren't sure what the issue was to begin with?

without any more details on your situation i'd suggest some basics first:
- check that your ride height front and rear is to spec per fsm
- check for ahc related dtc codes (obd will not show you these)
- and probably most importantly check your neutral pressure!!!! you can have perfectly functioning parts with sky high neutral pressure which will give you harsh ride despite good parts etc...
- also is your damping switch working?
- while probably unlikely it's possible that your new globes failed either due to defect, contaminated fluid etc. It's also possible one of your other parts failed. it's also possible height control ecu or something else you didnt replace is faulty... i would start with all the checks above but for testing globes you can do the reservoir gradations test, for any electronics dtcs would probably show, and there are diagnostic tests you can do with techstream software (or without) as documented in the fsm to check most of the electronic parts etc...

btw, can i get your old parts?...

Thanks for the post. Yes your right I did change the above mentioned stuff all by myself. The ride Not bouncy or harsh but there was too much cabin rattles. Unfortunately where I live there is no special tools to check the NEUTRAL pressure. With the new equipment the ride is almost same. Just swapped the rims/Tyres from my other 100 series and it's better. But still not that floating feel.

I flushed all the old liquid and feed it with new liquid. I change AHC liquid earlier than needed usually.

About the damping switch. I think I can't find much difference whereas on my other 100 its noticeable.

I don't have FSM. Where can I find one? Also how to bleed it properly? I start from Height control motor and then the wheel nearest to the motor till the farthest wheel.

The old stuff is with me still.

 

[cruiser03]

I did not see in your list of parts that you changed the rear shocks. I had the same issue, changed the rears and now it rides smooth.