Chevy Impala SS Forum banner

1 - 13 of 13 Posts

Registered
Joined
178 Posts
Discussion Starter #1
So, I just repaired the flappy exhaust and the melted air line to the passenger rear shock. Now I can't get the compressor to kick back on. I checked for power at the suspension compressor relay and found no power to any pin. I checked for power at the engine bay fuse for the ALC as well as the appropriate fuse in the dashboard fusebox - both had power.

I had to knock off further work due to the approach of night and mosquitoes, but in the morning, I intend to do the terminal B/yellow wire at axle level sensor jump I found here to see if I can't get the compressor to kick on, but is there any other way to jumper the compressor to get it to run? I can provide a direct connection to an external 12V source.

Does anyone have a wiring diagram/schematic for the air compressor module?

Also, should I go pull a used compressor from a junkyard, is there a way to test it with a battery off the car?

Any suggestions would be appreciated. My friend, the car's owner, is coming over for his annual road trip in just a couple days and we need this fixed so he can leave.

If it matters, the car is running AC Delco air shocks as recommended elsewhere on this forum and was already converted to use a parallel air system:
 

Registered
Joined
178 Posts
Discussion Starter #3
Thanks, that really helped. I found that this particular car does not have the five wires coming off the relay but four; applying 12V from the battery to the black and green wire at the relay connector would run the compressor and elevate the car, but there was a big leak from at least one of the shocks. This would be explained by the fact that while all the fuses checked out and were getting power, there was no power between the 30A underhood fuse and the orange wires at the compressor; we figure something cut the power and then the lack of a compressor and the broken line caused the bladders to fail.

Interestingly, in the year-plus we've had this car and heard/seen the compressor running (and raising the car), we've never seen a Level Ride light come on - which would appear to be the circuit missing at the compressor relay connector.
 

Registered
Joined
8,048 Posts
I hope your freind made it out for the trip with something functioning. There was plenty of chatter about the autolevel systems and airshocks overall when these cars were just 10 years old. Non-serviceable pumps, dying exhaust solenoids, chronic leaks, and of course the poor design premise of using shock mounts as a spring perch. Plenty of issues without even gertting into the poor quality dampening of typical oem airshocks compared to a legitimate performance shock.

Not tryna preach but for better than equal money my decision tree immediately steers to regular shocks and Airlift bladders. So easy to install both, and scads better performance each piece doing its own job. If you just gotta have that compressor at all then several JY options available (I recall '90's M/L and dustbuster minivans real plentiful/popular, but can't imagine many not crushed by now).

Sorry not helping with your diagnosis, but this subject got a "why keep bothering" from our cynical crowd quite a while back.
 

Registered
Joined
3,009 Posts
I hope your freind made it out for the trip with something functioning. There was plenty of chatter about the autolevel systems and airshocks overall when these cars were just 10 years old. Non-serviceable pumps, dying exhaust solenoids, chronic leaks, and of course the poor design premise of using shock mounts as a spring perch. Plenty of issues without even gertting into the poor quality dampening of typical oem airshocks compared to a legitimate performance shock.

Not tryna preach but for better than equal money my decision tree immediately steers to regular shocks and Airlift bladders. So easy to install both, and scads better performance each piece doing its own job. If you just gotta have that compressor at all then several JY options available (I recall '90's M/L and dustbuster minivans real plentiful/popular, but can't imagine many not crushed by now).

Sorry not helping with your diagnosis, but this subject got a "why keep bothering" from our cynical crowd quite a while back.
Very good post, except:

I wouldn't call it cynical to advocate dumping the ALC, but rather informed from experience and knowing there are much better alternatives.

That system is now about 40 years and little has changed since then. A set of Bilsteins and airbags (if you need auto leveling only) is the way to go.
 

Registered
Joined
178 Posts
Discussion Starter #6 (Edited)
He ended up heading out without the air bladders functional because we could not get replacement shocks or troubleshoot the electrical issue in the time remaining - the shocks work fine as is and the vehicle seems to be safe without them for now. When he returns with the car in a couple weeks, we'll be looking at what our best bet is going forward. We have KYB Gas-A-Justs on the front and they've done really well - might look up a set of those for the rear. We're not sure and it'll be a few weeks before he gets back and we can plan or do anything about it.

The initial decision to replace the blown shocks that came with the car with new AC Delco air shocks was made with the intent of preserving the original ride quality. Without considering options that would improve performance, are there any non-air shocks that are known retain the original ride quality?
 

Registered
Joined
8,048 Posts
Very good post, except:

I wouldn't call it cynical to advocate dumping the ALC, but rather informed from experience and knowing there are much better alternatives.

That system is now about 40 years and little has changed since then. A set of Bilsteins and airbags (if you need auto leveling only) is the way to go.
Concur all. And more just trying to let CB-'s friend down easy. Most of us got over airshocks with Gabriel Hyjackers holding up the L60-15s. However, I still say socially responsible transparency mandates divulging our demographic at every opportunity. The tri-9 B/D- crowd comprises either original owners characterized by a market leading unmeasurable contrivance quotient who had to part with a whole $25k to snag one new, or, there's the new wave of miscreant children picking these beaters up free for a couple thousand and antagonizing their millennial contemporaries at every opportunity with full-frame V8 heresy.

Full disclosure like this averts snowflakes wandering in from other forums and doing the knee-jerk good 'ol American compulsion of suing when they consider their sensibilities not adequately pandered to.

QUOTE CB700s - "Without considering options that would improve performance, are there any non-air shocks that are known retain the original ride quality?"

To retain original ride quality it'll take any sort of $11 shocks you find at Sears touting "oem replacement" or the cheapest possible option at parts houses. I just stuck Monroe Sev Serv all around my FWB with FE1 rears and chopped fronts and the rest of its setup. I'll be leaving them on = pretty nice.
 

Premium Member
Joined
1,586 Posts
Funny you mentioned L60s there Bob. I was driving the other day and thought of those too. Plus the Hi Jackers. But if you could get some N60s under there you were really "packin the meat." It was so much easier then, IMO. So good to have you back with your subtle replies.

BTW, OP. Have you thought about putting a grommet in there to keep the hose from rubbing against the metal? Maybe just cut the grommet and slip in there. Just a thought.

Mark: Snowman-33
 

Registered
Joined
178 Posts
Discussion Starter #9
Funny you mentioned L60s there Bob. I was driving the other day and thought of those too. Plus the Hi Jackers. But if you could get some N60s under there you were really "packin the meat." It was so much easier then, IMO. So good to have you back with your subtle replies.

BTW, OP. Have you thought about putting a grommet in there to keep the hose from rubbing against the metal? Maybe just cut the grommet and slip in there. Just a thought.

Mark: Snowman-33
When you guys were using L60s or N60s, were you also still using a hand crank to start the engine? Or was Flintstone vehicle propulsion de rigeur back then? :grin2:

At this point the owner is driving the car around the US on vacation and isn't reliably available for contact. I suspect we'll be talking about the rear suspension (among other squawks) once he gets back. We already have KYB monotube shocks in the front for better control and handling; since that's worked out very well for my tastes (and more importantly the owner's!) I for one am leaning towards simply obtaining two KYB monotube shocks for the rear, removing all the air ride gear, sticking it in a box in case some future owner or time comes around wanting to restore it to full original spec and calling it a day.
 

Registered
Joined
178 Posts
Discussion Starter #10
To retain original ride quality it'll take any sort of $11 shocks you find at Sears touting "oem replacement" or the cheapest possible option at parts houses.
Lovely. I'm a lot more used to vehicles that the manufacturer specified shocks on performance instead of "how cheap can we get 'some shock' to put on here?" With the exception of my Bronco, doing the Sears-style 'OEM replacement' or cheapest possible shocks at the usual suspects on my vehicles would result in extremely unpleasant ride and handling changes.
 

Premium Member
Joined
1,586 Posts
CB700S says,
vvvvvvvvvvv
When you guys were using L60s or N60s, were you also still using a hand crank to start the engine? Or was Flintstone vehicle propulsion de rigeur back then?


Almost but they were on one of these. Bought in 72 for $1000. Kinda simple to work on . No smog crap, lots of room in the engine compartment, hardly any plastic, terrible MPG but dayum they were fun. :wink2:
http://cdn.barrett-jackson.com/staging/carlist/items/Fullsize/Cars/137948/137948_Front_3-4_Web.JPG

Mark: Snowman-33
 

Registered
Joined
178 Posts
Discussion Starter #13
If the problem is no power to the compressor I would not give up just yet. He already spent the money on air shocks, may as well get all the use out of them.

93 Fleetwood with Auto Level rides high
It's not just no power to compressor, there's no power to any pin on the compressor relay. There's supposed to be a wire direct from the fuse to that relay plug and there's no voltage there. When the car gets back, I'll be inspecting the wiring harness from the fuse box (for safety if nothing else) but I don't know if my friend wants to keep working on this system (which has actually been the most repeatedly troublesome thing on the car) or if he just wants to upgrade and be done with it. His choice, of course.
 
1 - 13 of 13 Posts
Top