Hello,
I was hoping some of the AHC pros could be help me diagnose an issue. I have a 2000 Lexus LX470 Canadian model. I have a Rhino Rack, Columbus Variant RTT and a Alucab Shadow Awning mounted as well as a sleeping platform in the back. Not really much extra weight, maybe 250 lbs.
The story goes... about 1 month ago I had some noise in the front suspension. I dropped it off with my mechanic (not Lexus) to check it out and isolate it. The mechanic advised it was my sway bar bushing. He replaced the bushings.
I took a trip from Alberta to BC about 3 weeks ago for holidays. Had a Jumping Jack trailer on the hitch (light), but the LX was loaded up pretty good with coolers and kids etc. No real issues to speak of though. I noticed the AHC in L a couple of times, but would readjust to N.
About a 2 weeks ago, I noticed another annoying squeak in the front suspension. I dropped it off with the mechanic again who isolated it to the front right shock bushing. The penetrating oil made the noise go away so I figured I would leave it for now and see if it came back before replacing the bushing.
When I went to pick up the vehicle I hopped into the truck fired it up and noticed that the AHC was Off on the dash. I then noticed that the front was raked up high and the rear was low. Upon driving it was incredibly bouncy. Would not go into L or H. I limped it home and called the mechanic the next day inquiring as to if he maybe knocked the height sensor or used the AHC while the vehicle was suspended. He says nay.
I decided to bleed the system out and replace the AHC fluid. The fluid was very dark and I definitely saw some air bubbles. So much so I wasn't content with the single flush and did a second one earlier this week. On the second flush the fluid looked clean (pink-ish) with few air bubbles. I also popped off the right height sensor to see if I could examine any damage, or corrosion looked clean and perfect inside. I put it back on.
The system re-pressurized, but was still high in the front and a little bit bouncy, but not as bad. All my reading on similar issue threads lead me to believe that I needed a Tech Stream to figure WTF was up. Ordered up the cable and booted up the tech stream.
Here is the first data (remember I couldn't get from N to L). Pretty big delta on the FRH and FLH sensors. No trouble codes at all.
For giggles I moved the FRH sensor to the highest point in the bracket (did not change the adjuster but though). Here is the result on the TS.
Okay I pushed the AHC into low and drove a bit very slowly around the neighbourhood and it dropped into L. I connected the TS, then pushed N. Nothing happened, just a blinking light. Went for a drive and the system pushed into N. See below for the result in TS data. The MPA is really, really high. PS I pulled the temp sensor as recommended for pressure checks which produced the error code. Data for this posted in the below reply.
So, I'm inclined to start ratching up the torsion bars to try to reduce the MPA in the front system, but the rear is high too. I'm not really sure what to make of all this. I don't have super heavy bumpers or anything like that. With the pressures being so high is it fair to say that the pump and globes are good? I wonder if the height sensors are pooched and that's throwing everything out of order. Maybe my mechanic unknowingly reset the torsion bars when changing the sway bar bushing? Not really sure what to make of it all. Any thoughts or insight are very welcome!
Thanks in advance,
Dave
I was hoping some of the AHC pros could be help me diagnose an issue. I have a 2000 Lexus LX470 Canadian model. I have a Rhino Rack, Columbus Variant RTT and a Alucab Shadow Awning mounted as well as a sleeping platform in the back. Not really much extra weight, maybe 250 lbs.
The story goes... about 1 month ago I had some noise in the front suspension. I dropped it off with my mechanic (not Lexus) to check it out and isolate it. The mechanic advised it was my sway bar bushing. He replaced the bushings.
I took a trip from Alberta to BC about 3 weeks ago for holidays. Had a Jumping Jack trailer on the hitch (light), but the LX was loaded up pretty good with coolers and kids etc. No real issues to speak of though. I noticed the AHC in L a couple of times, but would readjust to N.
About a 2 weeks ago, I noticed another annoying squeak in the front suspension. I dropped it off with the mechanic again who isolated it to the front right shock bushing. The penetrating oil made the noise go away so I figured I would leave it for now and see if it came back before replacing the bushing.
When I went to pick up the vehicle I hopped into the truck fired it up and noticed that the AHC was Off on the dash. I then noticed that the front was raked up high and the rear was low. Upon driving it was incredibly bouncy. Would not go into L or H. I limped it home and called the mechanic the next day inquiring as to if he maybe knocked the height sensor or used the AHC while the vehicle was suspended. He says nay.
I decided to bleed the system out and replace the AHC fluid. The fluid was very dark and I definitely saw some air bubbles. So much so I wasn't content with the single flush and did a second one earlier this week. On the second flush the fluid looked clean (pink-ish) with few air bubbles. I also popped off the right height sensor to see if I could examine any damage, or corrosion looked clean and perfect inside. I put it back on.
The system re-pressurized, but was still high in the front and a little bit bouncy, but not as bad. All my reading on similar issue threads lead me to believe that I needed a Tech Stream to figure WTF was up. Ordered up the cable and booted up the tech stream.
Here is the first data (remember I couldn't get from N to L). Pretty big delta on the FRH and FLH sensors. No trouble codes at all.
For giggles I moved the FRH sensor to the highest point in the bracket (did not change the adjuster but though). Here is the result on the TS.
Okay I pushed the AHC into low and drove a bit very slowly around the neighbourhood and it dropped into L. I connected the TS, then pushed N. Nothing happened, just a blinking light. Went for a drive and the system pushed into N. See below for the result in TS data. The MPA is really, really high. PS I pulled the temp sensor as recommended for pressure checks which produced the error code. Data for this posted in the below reply.
So, I'm inclined to start ratching up the torsion bars to try to reduce the MPA in the front system, but the rear is high too. I'm not really sure what to make of all this. I don't have super heavy bumpers or anything like that. With the pressures being so high is it fair to say that the pump and globes are good? I wonder if the height sensors are pooched and that's throwing everything out of order. Maybe my mechanic unknowingly reset the torsion bars when changing the sway bar bushing? Not really sure what to make of it all. Any thoughts or insight are very welcome!
Thanks in advance,
Dave