the active is alive!!

[3Q Jay]

driven about 30 miles now. First few miles every 'new event' would trigger some burping, gradually subsiding. still sounds like chubacca occasionally, but it IS active. not like riding on a cloud, but nice. stays ABSOLUTELY flat in right turns at 25-30 mph.

few observations: the rear is nice & springy with car off. rear height does not seem to change after shutdown or on startup. front feels quite hard with engine off. raises about 1.5 inches on startup, and then has 'give'. all of this could be transient until i get a few more miles on her, just don't know.

i can definitely 'hear' the ps/active pump now while driving. has a slight turbine sound to it, varys with revs. This turbine sound was louder during the first 5 miles of driving, and has subsided a bit, but is certainly still there. i can also feel the pump kick in and out occasionally while steady throttle at about 1700 revs. kinda like a 2x a/c load on/off.

The book says right to left height should be within 10 mm. although I haven't 'measured' the wheel arch height, standing about 15 feet away in front or in back will tell me clearly that the right side is lower than the drivers side. Is this a pre-set feature to compensate for driver weight?

I was wearing a smile a lot even during that first drive.The answer to my wife's question 'well.....' when I returned was-- I LIKE this car!

Modified by GQ Jay at 10:30 PM 5/18/2005
Modified by GQ Jay at 10:30 PM 5/18/2005

[FarFetched]

It is always a good feeling when job is done right and outcome is what you have expected!Excellent !

[maxnix]

Saving an active is surely a good reward. Well done.

[elwesso]

GREAT NEWS!!! Another active Q saved and a pristine one at that!!!

I think give it time to adjust itself to the system actually working again and it will be OK.. I need to scan in my article of active vs standard Q.. truely fascinating...

You may need to adjust your height sensors...

[PalmerWMD]

Its alive, aliiiiivveee Muah hahaha.

Sorry got a bit carried away...old scientist joke..

Fred..

[Heath]

I need to scan in my article of active vs standard Q.. truely fascinating...

Please do!!!

[redmanfx]

GQ Jay you shouldn't really hear the active pump once it gets going. The pump is way up front and is a cresent design which isn't really loud. I'm curious to see if this pump continues to be heard. Normally the power steering pump is what people hear thinking it's the pump accumulator. The power steering pump "revs" up at RPM. Check the belts and all your fluids. Maybe Keith will chime in.

Congrats on the Q!! I'm tearing mine up....

red

[3Q Jay]

thanks guys--it is rewarding. took the long way home from work today, so i could do some sweeping "s". car felt real solid even at 70 in the sweepers.

i'm going to chill a bit and let everything settle before dinkin with the height switches. does look real easy to adjust though...at least in front.

Red, reason i thought the active pump is that there is a hummm down the left frame rail. meant to ask you -how is your project going?

[Jehangir]

Hey GQ how difficult was it to get to the Fore/aft G sensor. I took the center console off on mine, and right behind the shifter was this gold metal box looking thingy. I think this may have been it, but I'm not too sure. Also I didn't see any wires comming out of it. When I bought the car the active resevoir was empty. I wonder if having air in the system would result in sensor failures? Hmmmm

[3Q Jay]

uhhh, i don't know--i didn't mess with them. service history shows lateral g sensors 1&2 replaced exactly 13 months and 2740 miles ago. i wonder if they were really bad, or if the infiniti service guys didn't have a clue and were just throwing parts at it.

[3Q Jay]

Keith says multivalve unit *might* be bad based on my reports of 'limit-cycle' noise coming from LF.

says it won't hurt to drive , but is annoying [not to mention i sure get some funny looks.....]

[elwesso]

Id take my service manaul to the dealer and have htem do all the tests on the active suspension.. assuming they stll have the consult card for the active?

[pretzelboy]

Sweeet! Can't wait for my test ride.....work was tough this week----I'll call.

[tkd_q45]

GQ Jay - Please futher enighten me on the "chubacca" sounds from your multivalve. My drivers side front strut is makeing a lot of chattering/squeaking/grinding noises (intermittently). I'm thinking of trying to replace the front accumulators but don't want to have my car making other annoying noises. How often does this Wookie groaning noise happen? How loud? Do people turn there heads? Do pedestrians jump out of the way? I hesistate to spend money on something that may not work and or cause yet another issue. Any input would be greatly appreciated!

[Jehangir]

GQ Jay - Please futher enighten me on the "chubacca" sounds from your multivalve. My drivers side front strut is makeing a lot of chattering/squeaking/grinding noises (intermittently). I'm thinking of trying to replace the front accumulators but don't want to have my car making other annoying noises. How often does this Wookie groaning noise happen? How loud? Do people turn there heads? Do pedestrians jump out of the way? I hesistate to spend money on something that may not work and or cause yet another issue. Any input would be greatly appreciated!

The Accumulaters will not add or remove noise from your actuator area. Initially after changing your nitrogen filled beauties, you will hear funny groans and creaks but that all goes away within a hour of driving. I have been having a clunking sound comming from my front actuator area as well. Subsequently, I have changed my upper links, tension rod and sway bar bushings. But the noise persists. I had to do the aforementioned work anyway, but just thought this may help.Good Luck

[texasoil]

Sometimes the brake caliper/pads will 'clunk' on sharpbumps. Try lightly pressing the brake pedal and see if the noise changes/vanishes. A bad lower control arm inner bushing will make noise, as will lots of other things. I once hunted for a 'clunk' for a year and finally found--thebolts attaching the front mount for the tension arm were loose and allowing that frame member to shift.

It is rare for an 'actuator' to fail internally, but not unheard of. If bleedig all the air out the top doesn't stop a definitely internal noise--you're a winner! However, a chattering/squealing/groaning noise that comes from the left front fender well MAY well be the MULTIVALVE. One way to diagnose is to crack open the pressure bleed screw (not the small brake bleeders for air venting) on the control valve in the right front (the front pressure control valve). Usually opening the bleeder 1/8-1/4 turn is enough to change the hydraulic circuit resonant frequency enough to stop the noise. No real harm in leaving it cracked open--just wastes a little high pressure oil back to the reservoir.

The dynamic frequency response of the several pressure control circuits change with fluid viscosity and system wear. Their interactions will cause instability (chattering, squealing, groaning, loss of control stability) if the system response characteristics move too close to 'perfect'. What is necessary is some amount of 'negative feedback' in the main pressure control circuit to ensure control loop stability--and bleeding a little oil from the high pressure loop provides that little bit extra that's needed. The 'math' gets real hairy, and the logic is not trivial. The 'active computer' has LOTS of inputs it uses to electrically modify the control algorithims and implement changes, and it is highly optimized to minimize energy consumption---at the cost of extremely precise clearances in the valves. This is why it is CRITICAL you change the fluid every 60K miles and keep it clean.

[3Q Jay]

GQ Jay - Please futher enighten me on the "chubacca" sounds from your multivalve. My drivers side front strut is makeing a lot of chattering/squeaking/grinding noises (intermittently). I'm thinking of trying to replace the front accumulators but don't want to have my car making other annoying noises. How often does this Wookie groaning noise happen? How loud? Do people turn there heads? Do pedestrians jump out of the way? I hesistate to spend money on something that may not work and or cause yet another issue. Any input would be greatly appreciated!

tkd_ Keith's post immediately above cover this. I did the procedure he outlined above and it took care of the wookie noise. i may have to revisit this work-around as a long term fix, but it did solve my immediate problem, and i don't get those puzzled looks from innocent bystanders anymore.

[Q_SHIP]

Who was it that had picture of their active on a curb? If I remember correct, it was a green one.

[elwesso]

zerothread?id=119803

[3Q Jay]

Keith- it's good to have you back and hope the recovery is going well.

[GreenQ45a]

That's what I'm talking about...

More active Q45a's on the road...

Good job!!!

Now all you need is an Active Suspension Controller!

The system is only half of what it can be without one.

I am doing a write up on it with Pictures and Video it is just taking awhile because I just moved to town from the mountians and a few other reasons.

Anyway GREAT job!

GreenQ45a

PS It was my Q45a playing on the curb...

[tkd_q45]

Kieth as always, thanks for your input. I will try the pressure thing.

Don't know if I've mentioned this before but my car does "jump" up on the fwy under certain conditions. Seems to be a particular short stretch of pavement on a hwy I commute on daily. Can't say there's anything unusual about this stretch of road, just typical concrete w/sublte expansion joints. When I had my front end "lowered" via the ride hieght sensors my front end would jump up (jump up, hold for a second, then go back down). Now I've increase my front ride hieight (actually a bit too high now) but on this same stretch of road, my back end now jumps up.

I've tried braking when I hear the grinding/chattering noises but it's hard to say as it is bumps/dips that make the noise happen and I can't react fast enough. It is getting more frequent. Seems to happen a lot over speed bumps in the parking lot I park in daily.

[3Q Jay]

Tom- let me know if you want to bring your Q and we try the texasoil thing on yours. like i said, it did silence the wookie.

[tkd_q45]

Jay - Certianly - what had you in mind?

[3Q Jay]

you wanna head this way? sent you an e-mail.

Jay

ummm check that...e-mail bounced from the adelphia account.

[email protected]
Modified by GQ Jay at 12:08 PM 9/17/2005

[tkd_q45]

Jay check your email.

[texasoil]

If the rear (or front) is 'jumping' either up or down that indicates height control instability, which is caused by a similar set of circumstances as the 'squealing/groaning',but at a drastically different frequency. the pressure control valve shuttle proper has a natural resonant frequency that ranges from around 5 cps to 2000cps (changes with system pressure). The high pressure fluid spillback will stabilize the control valve oscillation, but probably not the height control instability. The 'height control' function has a resonant frequency that will appear at around 0.5 cps.--but only if the control shuttles in the valves are worn or the fluid viscosity is too low. Either condition allows high presure fluid to 'leak' into the struts raising the car and the computer has to increase the solenoid power to force the control valve shuttle farther back against the high pressure. When the solenoid can no longer provide enough balancing force, the height control system 'saturates' in process control terms and you lose height stability.

On each pressure control valve (one for each wheel--2 in right front valve, 2 in right rear valve) there is a 'balance spring' adjustment set at the factory to precisely balance the shuttle valve so maximum computer control range is available via the solenoid. You now have insufficient spring pressure to properly balance the shuttle and the solenoid canot control the height (pressure in the struts)

The'adjustment' is on the opposite end of each control valve from the 'brake-bleeder'. At your own risk, you might try loosening the lock nuts and screwing IN 1/4 turn max (at a time) on the offending control valve (if you can isolate to one valve or both if you cannot.) Then test drive it to see if it improves. Before doing that though, do check the electrical connections to the solenoids to ensure a poor connection is not causing the 'loss of control' situation.

Be careful and patient and keep note of what you did. MARK the adjustment bolts so you can return them to the original position if necessary.. Without a very expensive(+/-$50K hydraulic test bench to work with, you can easily get the valves all screwed up and then you have no choice but to replace it.

A more 'elegant' solution is to monitor the voltage to each solenoid (output from the active computer as it tries to control the height) and adjust the springs to put the solenoids in the middle of its operating voltage range. That's the way the factory does it with the hydraulic test bench. The'worst case' for height control is with minimum weight in the car.

[tkd_q45]

GQ Jay -

Thanks again for the help & insight. It was great to get in person input from a fellow "a" owner.

Definitely less groaning/creaking/chattering on the way home, but more rear lifting as well (similar to when you bounced the rear - sticking then dropping). I did get a bit more chattering as I neared my neighborhood (approx 34 miles into my drive back).

[3Q Jay]

Tom, it was a pleasure.

Give it some time and see what you want to do. I only moved that valve 1/16-1/8 of a turn, if you decide you want to put it back. i really think you need to do your accumulators to get the system back and then work out any remaining bugs. your active is too nice to convert.

now that I'm 'experienced', we could change out all 9 in a day--just let me know.

[tkd_q45]

OK - so I did the daily commute - 37 miles each way from PV/RHE to Glendale.

My active is the most "active" it's been. It's pretty decent on surface streets. But once I get on the 110 Harbor Fwy the rear sticks (as it did when you bounced it in your garage) more than it did before. Definitely less chatter/squeaking especially in the parking structure where I park. In fact there is a patch of the structure that always elicits the same creaking/groaning every time I drive over it - since the adjustment there is no creaking/groaning!

The only shortcoming is the extra rear jumping on the fwy. Otherwise it was a pretty good move.