Getting right down to it...

Notable issues, as outlined in the title.

1. HEAT! 59 degrees this evening as I was driving home. Set ECC to AUTO 75 as I normally would in the truck and get a very mild stream of warm dry air...nope..the Bonneville gives me INSANELY cold air conditioned air. I turn it up to 80, it responds by raising the fan speed up to full, with more freezing cold air. Up to 85, then 90 it goes, MORE freezing air. So, I did the quick logical pattern of, turn off, try again...nope...so I turn it all the way down to 60, wait for the air mix actuator to change, and then back up to 90, NOW it blows hot. After about 3 mins of driving with it at 90, it gets a little TOO hot...and so I just lower it down one notch, to 85, and it starts pushing lukewarm/cool air again.

On a sidenote...I need to do the evap cleaning process...because when it's hot out...the A/C could use a little help..and the refrigerant is at the level it should be.

2. Flashing temperature setting? Usually it'll be just after I start the car up, but its getting quite common to where the ECC will sit there and flash the set temperature at me for a couple minutes, no matter where I put it...and then..all of a sudden, it'll go back to the normal outside temp, and stop flashing. Don't get it.

3. It is my understanding that the cabin temperature sensor is in that grilled place right next to the cigarette lighter on the dash? Well...going along with problem number 1 on this list...it doesn't seem to be doing its job very well. When it's hot out...the ECC doesn't seem to cooperate and give me cold air unless I demand something obscenely low like 65 degrees, or sometimes even 60 to get some decently cool airflow.

If this ECC system made any LESS sense, and was any less functional..I'd smash it with a hammer.

I can understand that the air mixer probably is lacking some vacuum it should have due to some line rottage, but STILL...the least I can ask of the ECC is that it give me the correct temperature!

_________________
John
Now: '15 Toyota Prius III | 134 hp 2ZR-FXE | Silver | 36k
Now: '03 Honda CR-V AWD | Slow 4-Cylinder | Dirt | 180k
Then: '07 Ford Fusion SEL | 221hp Gen I VVT Duratec 3.0 V6 | Tungsten Silver | 150k
Then: '99 Toyota Avalon XL | 200hp 1MZ-FE 3.0 V6 | Diamond White | 189k | Sold: July 2015
Then: '11 Ford Fusion SEL | 240hp Gen II VVT Duratec 3.0 V6 | Ingot Silver | 84k | Totaled: Oct 23 '14 (Rear-Ended)
Then: '96 Buick Park Avenue Ultra | 240hp Series II L67 | Medium Dark Lichen | Bought: JAN 11 @ 135k | Accident: FEB 3 '12 | Crushed: MAR 1 '13 @ 153K
Then: '98 Pontiac Bonneville SSE | 205hp Series II 3800 L36 | Topaz Firemist | Bought: NOV '09 @ 74k | Accident: MAY 28 '10 | Crushed: MAR 15 '11 @ 84k
Then: '93 Pontiac Bonneville SE | 170hp Series I 3800 L27 | Dark Yellow Green | Bought: JULY '07 @ 92k | Sold: JULY '12 @ 118k
Then: '89 Pontiac Bonneville LE | 165hp 3800 LN3 | Medium Garnet Red | Bought: JAN '05 @ 117k | Sold: SEP 30 '07 @ 152k

Everything is pointing to the airmix actuator. The airmix doesn't use vacuum, it is purely stepper-motor driven. The only thing that is vac driven is the air diverter flaps.

Flashing EEC could indicate the airmix going bad, or it could also mean that the battery was disconnected within 50 ignition cycles. Mine flashes all the time now because of loss of serial data communication...doesn't affect operation, but you can't communicate with the system anymore either.

_________________
2005 GXP - White Gold Pearl, no mods...yet.
2000 SSEi - Resurrection in progress. Built L67 w/L32 fuel rail, ported heads, and cam. Camaro front brake system, GXP cluster, and much more in planning.

Can you expand on the "comunicate withe the system" part of your post? The ECC in our '94 was all wonky late summer, and I've had a couple days where I got cold air instead of heat. But recently I've taken to pausing when I turn the key to start, and letting the dials all sweep, and I can hear what I imagine is the actuator moving in the dash as well.

And I've had HEAT, which is nice. I was really thinking I had a bad air-mix actuator, but now I'm not so sure. Would love to be able to pinpoint the real issue, as my temp display flashes too, occasionally.

I have had the battery disconnected, but no other issues that I've noticed.

_________________
TomS.
1994 Pontiac Bonneville SSEi
sold Dec, 2014

The "loss of serial data communication" is a rare event in the ECC world. Mine only happened because of this little project right here. Yours will also be the airmix actuator....9 times out of 10, that's the issue. There is a cog that develops a crack inside the actuator, causing the stepper shaft to spin freely instead of moving the cog, and by association the arm that controls the airmix door.

For Bonnevilles, it's a major pain in the arse to replace because of the dash design. I know mines on the fritz, and I will be replacing it when I have all the interior out of the car in a month or so.

_________________
2005 GXP - White Gold Pearl, no mods...yet.
2000 SSEi - Resurrection in progress. Built L67 w/L32 fuel rail, ported heads, and cam. Camaro front brake system, GXP cluster, and much more in planning.

Well..the battery has been disconnected within 50 ignition cycles...so that's in the normal range...but then again, it could also mean its going bad.

So...replacing that should solve all the issues you're saying?

_________________
John
Now: '15 Toyota Prius III | 134 hp 2ZR-FXE | Silver | 36k
Now: '03 Honda CR-V AWD | Slow 4-Cylinder | Dirt | 180k
Then: '07 Ford Fusion SEL | 221hp Gen I VVT Duratec 3.0 V6 | Tungsten Silver | 150k
Then: '99 Toyota Avalon XL | 200hp 1MZ-FE 3.0 V6 | Diamond White | 189k | Sold: July 2015
Then: '11 Ford Fusion SEL | 240hp Gen II VVT Duratec 3.0 V6 | Ingot Silver | 84k | Totaled: Oct 23 '14 (Rear-Ended)
Then: '96 Buick Park Avenue Ultra | 240hp Series II L67 | Medium Dark Lichen | Bought: JAN 11 @ 135k | Accident: FEB 3 '12 | Crushed: MAR 1 '13 @ 153K
Then: '98 Pontiac Bonneville SSE | 205hp Series II 3800 L36 | Topaz Firemist | Bought: NOV '09 @ 74k | Accident: MAY 28 '10 | Crushed: MAR 15 '11 @ 84k
Then: '93 Pontiac Bonneville SE | 170hp Series I 3800 L27 | Dark Yellow Green | Bought: JULY '07 @ 92k | Sold: JULY '12 @ 118k
Then: '89 Pontiac Bonneville LE | 165hp 3800 LN3 | Medium Garnet Red | Bought: JAN '05 @ 117k | Sold: SEP 30 '07 @ 152k

The key word is "should". Starting in '94, the ECC lost the ability for the owner to get the trouble codes themselves....it has to be taken into the dealer to get the codes from that year on. So there is no way of knowing, unless you take into the dealership, if the airmix is the issue or not. Good chance that it is, but no 100% guarantees.

_________________
2005 GXP - White Gold Pearl, no mods...yet.
2000 SSEi - Resurrection in progress. Built L67 w/L32 fuel rail, ported heads, and cam. Camaro front brake system, GXP cluster, and much more in planning.

Just a small noted thing here.

If the ECC is off..and you get a flashing EXT temp...would this mean something else is wrong besides the mix actuator? Just sort of odd for it to be doing it just after working fine (caused again because i disconnected the battery. )

Everything in the FSM starts with "Install a Scan Tool" but from what I can tell, a flashing EXT temp means there's a fault, and ECC DTC, but is it just telling me there's one in general? or that its something specific in that off mode?

Guess I'll just have to replace the air mix and hope it goes away.

Edit: Also, I forgot that a few times this week, I started the car, and just got "---" on the ECC screen, with it obviously actuating its last setting (air was blowing the same way when I shut it off). It didn't come back for about 5 minutes, and then acted like nothing was wrong.

_________________
John
Now: '15 Toyota Prius III | 134 hp 2ZR-FXE | Silver | 36k
Now: '03 Honda CR-V AWD | Slow 4-Cylinder | Dirt | 180k
Then: '07 Ford Fusion SEL | 221hp Gen I VVT Duratec 3.0 V6 | Tungsten Silver | 150k
Then: '99 Toyota Avalon XL | 200hp 1MZ-FE 3.0 V6 | Diamond White | 189k | Sold: July 2015
Then: '11 Ford Fusion SEL | 240hp Gen II VVT Duratec 3.0 V6 | Ingot Silver | 84k | Totaled: Oct 23 '14 (Rear-Ended)
Then: '96 Buick Park Avenue Ultra | 240hp Series II L67 | Medium Dark Lichen | Bought: JAN 11 @ 135k | Accident: FEB 3 '12 | Crushed: MAR 1 '13 @ 153K
Then: '98 Pontiac Bonneville SSE | 205hp Series II 3800 L36 | Topaz Firemist | Bought: NOV '09 @ 74k | Accident: MAY 28 '10 | Crushed: MAR 15 '11 @ 84k
Then: '93 Pontiac Bonneville SE | 170hp Series I 3800 L27 | Dark Yellow Green | Bought: JULY '07 @ 92k | Sold: JULY '12 @ 118k
Then: '89 Pontiac Bonneville LE | 165hp 3800 LN3 | Medium Garnet Red | Bought: JAN '05 @ 117k | Sold: SEP 30 '07 @ 152k

I'm looking at the RPO C68, GM# 16141822, Delco# 1571923

Is this the part I need?

_________________
John
Now: '15 Toyota Prius III | 134 hp 2ZR-FXE | Silver | 36k
Now: '03 Honda CR-V AWD | Slow 4-Cylinder | Dirt | 180k
Then: '07 Ford Fusion SEL | 221hp Gen I VVT Duratec 3.0 V6 | Tungsten Silver | 150k
Then: '99 Toyota Avalon XL | 200hp 1MZ-FE 3.0 V6 | Diamond White | 189k | Sold: July 2015
Then: '11 Ford Fusion SEL | 240hp Gen II VVT Duratec 3.0 V6 | Ingot Silver | 84k | Totaled: Oct 23 '14 (Rear-Ended)
Then: '96 Buick Park Avenue Ultra | 240hp Series II L67 | Medium Dark Lichen | Bought: JAN 11 @ 135k | Accident: FEB 3 '12 | Crushed: MAR 1 '13 @ 153K
Then: '98 Pontiac Bonneville SSE | 205hp Series II 3800 L36 | Topaz Firemist | Bought: NOV '09 @ 74k | Accident: MAY 28 '10 | Crushed: MAR 15 '11 @ 84k
Then: '93 Pontiac Bonneville SE | 170hp Series I 3800 L27 | Dark Yellow Green | Bought: JULY '07 @ 92k | Sold: JULY '12 @ 118k
Then: '89 Pontiac Bonneville LE | 165hp 3800 LN3 | Medium Garnet Red | Bought: JAN '05 @ 117k | Sold: SEP 30 '07 @ 152k

John, if you disconnected the battery, the flashing display would be a normal thing for 50 ignition cycles. It could also mean that the refrigerant level is too low...but the compressor would not kick on if that were the case.

_________________
2005 GXP - White Gold Pearl, no mods...yet.
2000 SSEi - Resurrection in progress. Built L67 w/L32 fuel rail, ported heads, and cam. Camaro front brake system, GXP cluster, and much more in planning.

Well...since I know I've started it well over 50 times since I last disconnected the battery...it brings me down to knowing at LEAST two things are wrong.

In the FSM, it will tell you that if the Air Mix Actuator is not functioning, you can only use the highest or lowest settings for hot or cold. This is a present condition. This tells me that is necessary to replace.

Question about that. Are there more than one that need replacing? The FSM refers several times to a passenger and driver air mix actuator, but I believe that to only be on the Buicks and Oldsmobiles?

And then of course, my most late issue...the ECC screen will go blank, with 3 dashes across it quite often now. It will do it at least 3/5 times when I start the car up, and will stay blank for at least a minute, and then will return to a normal screen, with of course, the temperature flashing. It also appeared for the first time when the ignition cycle wasn't broken! I had the ignition on without the engine running, testing out my new speakers, and had the ECC off. It was displaying the outside temp, when, out of nowhere, the 3 dashes showed up, and the blower motor turned on to the medium setting. And of course, when it's in this mode, it won't respond to any button inputs. I cycled the ignition, and got the same response from it.

And the third, possibly isolated occurance is when I'll start the car up, and have the ECC off, the outside temperature will blink. I assume this is just notifying me of a stored DTC in the system, but just making sure that isn't telling me that something's wrong with my outside temperature sensor.

The only thing that shows in the FSM for 'blank ECC DIC' is something about the ambient temperature sensor being open or shorted....and yet, 80% of the time, its dead on accurate, and working fine? Makes me feel like the ECC is in cahoots with my third brake light intermittently working.

_________________
John
Now: '15 Toyota Prius III | 134 hp 2ZR-FXE | Silver | 36k
Now: '03 Honda CR-V AWD | Slow 4-Cylinder | Dirt | 180k
Then: '07 Ford Fusion SEL | 221hp Gen I VVT Duratec 3.0 V6 | Tungsten Silver | 150k
Then: '99 Toyota Avalon XL | 200hp 1MZ-FE 3.0 V6 | Diamond White | 189k | Sold: July 2015
Then: '11 Ford Fusion SEL | 240hp Gen II VVT Duratec 3.0 V6 | Ingot Silver | 84k | Totaled: Oct 23 '14 (Rear-Ended)
Then: '96 Buick Park Avenue Ultra | 240hp Series II L67 | Medium Dark Lichen | Bought: JAN 11 @ 135k | Accident: FEB 3 '12 | Crushed: MAR 1 '13 @ 153K
Then: '98 Pontiac Bonneville SSE | 205hp Series II 3800 L36 | Topaz Firemist | Bought: NOV '09 @ 74k | Accident: MAY 28 '10 | Crushed: MAR 15 '11 @ 84k
Then: '93 Pontiac Bonneville SE | 170hp Series I 3800 L27 | Dark Yellow Green | Bought: JULY '07 @ 92k | Sold: JULY '12 @ 118k
Then: '89 Pontiac Bonneville LE | 165hp 3800 LN3 | Medium Garnet Red | Bought: JAN '05 @ 117k | Sold: SEP 30 '07 @ 152k

The airmix actuator code could be causing all your issues. I had very similar issues on both of my cars at different times. There is only one actuator on your car, and the record for replacement is under 25 minutes if you care to go after it.

I suggest doing the actuator and then see how things work. Make sure you get the adjustment right, or at the very least, make sure there's the same amount of actuator shaft sticking out of the retainer after you replace it.

_________________

Click here for mod list for both cars
93 SSEi, 95 SLE (supercharged) 97 Buick LeSabre Limited
PontiacDad at WCBF '04: Cruise control? That's like surrendering!
Comprehensive guide to troubleshooting, rebuilding, and modifying Eaton Superchargers

Thanks Bill, and this is the correct part?

_________________
John
Now: '15 Toyota Prius III | 134 hp 2ZR-FXE | Silver | 36k
Now: '03 Honda CR-V AWD | Slow 4-Cylinder | Dirt | 180k
Then: '07 Ford Fusion SEL | 221hp Gen I VVT Duratec 3.0 V6 | Tungsten Silver | 150k
Then: '99 Toyota Avalon XL | 200hp 1MZ-FE 3.0 V6 | Diamond White | 189k | Sold: July 2015
Then: '11 Ford Fusion SEL | 240hp Gen II VVT Duratec 3.0 V6 | Ingot Silver | 84k | Totaled: Oct 23 '14 (Rear-Ended)
Then: '96 Buick Park Avenue Ultra | 240hp Series II L67 | Medium Dark Lichen | Bought: JAN 11 @ 135k | Accident: FEB 3 '12 | Crushed: MAR 1 '13 @ 153K
Then: '98 Pontiac Bonneville SSE | 205hp Series II 3800 L36 | Topaz Firemist | Bought: NOV '09 @ 74k | Accident: MAY 28 '10 | Crushed: MAR 15 '11 @ 84k
Then: '93 Pontiac Bonneville SE | 170hp Series I 3800 L27 | Dark Yellow Green | Bought: JULY '07 @ 92k | Sold: JULY '12 @ 118k
Then: '89 Pontiac Bonneville LE | 165hp 3800 LN3 | Medium Garnet Red | Bought: JAN '05 @ 117k | Sold: SEP 30 '07 @ 152k

Which car?

_________________

Click here for mod list for both cars
93 SSEi, 95 SLE (supercharged) 97 Buick LeSabre Limited
PontiacDad at WCBF '04: Cruise control? That's like surrendering!
Comprehensive guide to troubleshooting, rebuilding, and modifying Eaton Superchargers

Sorry, 98 SSE. The 93 SE has manual climate control.

_________________
John
Now: '15 Toyota Prius III | 134 hp 2ZR-FXE | Silver | 36k
Now: '03 Honda CR-V AWD | Slow 4-Cylinder | Dirt | 180k
Then: '07 Ford Fusion SEL | 221hp Gen I VVT Duratec 3.0 V6 | Tungsten Silver | 150k
Then: '99 Toyota Avalon XL | 200hp 1MZ-FE 3.0 V6 | Diamond White | 189k | Sold: July 2015
Then: '11 Ford Fusion SEL | 240hp Gen II VVT Duratec 3.0 V6 | Ingot Silver | 84k | Totaled: Oct 23 '14 (Rear-Ended)
Then: '96 Buick Park Avenue Ultra | 240hp Series II L67 | Medium Dark Lichen | Bought: JAN 11 @ 135k | Accident: FEB 3 '12 | Crushed: MAR 1 '13 @ 153K
Then: '98 Pontiac Bonneville SSE | 205hp Series II 3800 L36 | Topaz Firemist | Bought: NOV '09 @ 74k | Accident: MAY 28 '10 | Crushed: MAR 15 '11 @ 84k
Then: '93 Pontiac Bonneville SE | 170hp Series I 3800 L27 | Dark Yellow Green | Bought: JULY '07 @ 92k | Sold: JULY '12 @ 118k
Then: '89 Pontiac Bonneville LE | 165hp 3800 LN3 | Medium Garnet Red | Bought: JAN '05 @ 117k | Sold: SEP 30 '07 @ 152k

Well...I've been having a load of issues with my ECC in recent days not responding at all to cold settings...it'll just blow blazing hot air at me, with the exception being when it'll once in a while flash the temp and then try to fix it, eventually making itself work.

So tonight, I started looking at the vac lines...replaced a couple under the hood...and then decided to dig in under the dash. (in hindsight, i wish i had left it alone.) I went digging to see if there were any disconnected vac lines, loose connections, etc...well..that's *dang* difficult to get to under there, so I pulled down the HVAC Programmer to make myself a hole...but unfortunately, I didn't disconnect it from the Airmix Actuator..and took all the electrical pins with the plug. So that's one thing. Second thing is that I realized that the large interior air sensor spring like tube thing (for a lack of a better description), was sitting on top of the air mix arm...because it wasn't properly clipped away from the actuator the last time someone was up there.

So..I destroyed the actuator, and also discovered the problem, all in one.

Now, as for Bill's claimed 25 minute record replacement of this item...HOW THE HELL that's possible but anywhere else not in this dimension, I don't know...because I just can't get to it at any sort of angle to understand its R&R without just going right ahead and removing the dash and going after it. The FSM is about as helpful as a haynes manual at this point since it just essentially says to remove the dash, or magically reach from underneath (but I really don't see how it's humanly possible to disconnect the connector from the airmix coming from the programmer unless you did it from the top. It's all the airbag's fault.

I might be removing the seat.

I'll try and get ahold of one tomorrow on the other coast and throw it all back together, even if it works the same as it did..I won't argue too much..and if it works better, then hey, awesome.

_________________
John
Now: '15 Toyota Prius III | 134 hp 2ZR-FXE | Silver | 36k
Now: '03 Honda CR-V AWD | Slow 4-Cylinder | Dirt | 180k
Then: '07 Ford Fusion SEL | 221hp Gen I VVT Duratec 3.0 V6 | Tungsten Silver | 150k
Then: '99 Toyota Avalon XL | 200hp 1MZ-FE 3.0 V6 | Diamond White | 189k | Sold: July 2015
Then: '11 Ford Fusion SEL | 240hp Gen II VVT Duratec 3.0 V6 | Ingot Silver | 84k | Totaled: Oct 23 '14 (Rear-Ended)
Then: '96 Buick Park Avenue Ultra | 240hp Series II L67 | Medium Dark Lichen | Bought: JAN 11 @ 135k | Accident: FEB 3 '12 | Crushed: MAR 1 '13 @ 153K
Then: '98 Pontiac Bonneville SSE | 205hp Series II 3800 L36 | Topaz Firemist | Bought: NOV '09 @ 74k | Accident: MAY 28 '10 | Crushed: MAR 15 '11 @ 84k
Then: '93 Pontiac Bonneville SE | 170hp Series I 3800 L27 | Dark Yellow Green | Bought: JULY '07 @ 92k | Sold: JULY '12 @ 118k
Then: '89 Pontiac Bonneville LE | 165hp 3800 LN3 | Medium Garnet Red | Bought: JAN '05 @ 117k | Sold: SEP 30 '07 @ 152k