Hello everybody,

Just joined the Bonnie club yesterday, bought a 2000 SSEI with 61k original miles. It was cared for meticulously in its first 3/4 of life but had been a little neglected towards the end with the owner passing away and grandchildren began driving the vehicle. Any help would be greatly appreciated.


First things first the car has an odd rather loud droning type of noise at idle. It sounds like it’s coming from the supercharger but it doesn’t sound quite right to me. (Never heard one of these cars run before so it may not be abnormal) There is also some odd green/grey gunk built up in the engine bay that looks like it’s being flung by the belt. (Video link below)

https://youtube.com/shorts/s81IZ67ZZWw? ... duNPKfV4Jk

Next subject of interest is a loud whining/hissing/whistling noise coming from engine bay after driving and shutting the engine off. It only lasts for about 30 seconds and then is gone. It sounds like it’s coming from the mid to lower back left of the engine. (2 videos below)

https://youtube.com/shorts/ZhDaeCAoZCM? ... Iw-gNnyqrR
https://youtube.com/shorts/avzd7SO8_58? ... BudE5OwtFm

When filming a 3rd video of the noise after driving I was able to spot a drip with the camera. Not sure if anyone could tell me if that is a common AC condensation drip point or not. Or maybe have the knowledge of what part would be leaking for a drip to happening there. (Video below)

https://youtu.be/a0HfMLl4v3M?si=AbtVNoUZACSPLYD3


The oil was changed about a month and a half ago and the fluids were topped off then according to seller. No lights on the dash at pickup. I noticed the coolant was low already after being topped off not long ago so I knew there would be some issues most likely but decided to purchase anyway because I couldn’t pass up the deal. I went straight to AUTOZONE and topped off the coolant.
I made about an hour and half drive on the interstate back home afterwards and at some point a service engine light came on. Read the codes and it turned out to be P0137 (O2 Bank 1, Sensor 2) current and a stored P0128 (coolant temp below thermostat regulating temperature). As far as I know the car has never had the LIM gasket upgraded/replaced could these symptoms be related to the LIM failing? I also checked the oil today and it is nearly a quart low and looks very dark for being changed so recently.

The readings for the P0128 state:

Calc Load: 20.3%
ECT: 195.8 F
STFT B1: 0.7%
LTFT B1: 14.8%
MAP: 32.1 in.
Engine RPM: 2234
Veh Speed: 81 MPH
MAF: 7.01 lb/min
TPS: 27.8%


Sorry for the long winded first post, just really want to get this baby back to tip top shape asap.
Any help is greatly appreciated!

Thank you,
Tyler

Found out that the build up of grey stuff in the bay is a busted CV Axle spraying out everywhere.

Any help on this buzzing/droning noise coming from the supercharger area would be greatly appreciated.

There is a video on youtube that mentions a bracket going from the alternator to somewhere (it doesn’t show or mention where the other end is) that is on most 3800 supercharged engines. It claims that if this is missing or not tightened enough it can produce a buzzing type sound. Mine does not have a bracket from the alternator as can be seen in the video of the noise. Should a 2000 Bonneville have this?

The whining noise is definitely coming from something belt driven. To eliminate the SC, just take off the SC belt. If the noise goes away, spin all the pulleys by hand to see if any of them feel rough or wobbly. If the noise doesn't go away, move on to the serpentine belt, remove it and spin the pulleys. You can run the car for a minute without the water pump turning and be ok.

The whistling noise sounds like the AC system pressure equalizing, completely normal. Might be just the video, but its usually more of a hissing sound than a whistling sound.

Yes there should be a support bar going from the top alternator bolt to the back of the supercharger. It holds the EVAP purse solenoid. I can see that you do have it properly installed in the video.

Don't trust any maintenance done by the previous owner. Always start fresh with your own service.

_________________
Andrew - owner/operator of Bonnevilles Unlimited

2004 Bonneville GXP | 60k | White Gold Tricoat | custom built supercharged 3800 hot rod | garage queen
1997 Corvette | 55k | Silver Metallic | Z06 wheels | Date-night Hauler/Parts runner
2014 Town & Country Limited | Cashmere Pearl | 95k | Family Hauler
2002 Ram 1500 Quad Cab Sport | Black| 260k | Official Bonneville Hauler

Really appreciate the help.

I was able to diagnose the noise to be coming from the supercharger belt path. 2 of the pulleys are little noisy while spinning and seem to be spinning a little too freely I’ll be replacing them. But my main concern now is that the super charger pulley is barely spinning at all. It has a good amount of resistance to it. I’ve attached a video below if you’d be able to advise me if this appears normal or not.

Thank you so much once again!

https://youtube.com/shorts/0KtIn928jWs? ... UK0KkJARpD

Just pulled the oil plug on the charger and I can so no visible oil at all. Have oil coming in tomorrow so I’ll fill it up then. It should be up to right below the first thread correct?

https://youtube.com/shorts/3kt4hOlnMD8? ... c_UDg65xbd

I agree with replacing those plastic pulleys with some new metal ones to help with the noise deduction and also to make it more reliable. Those plastic pulleys are known to grenade when the bearings start to get warm.

The supercharger will have some resistance to it, hard to convey how much over the internet. It certainly won't keep free spinning after letting go. The oil should be up to the threads, so yes it might be oil starved. Start there.

_________________
Andrew - owner/operator of Bonnevilles Unlimited

2004 Bonneville GXP | 60k | White Gold Tricoat | custom built supercharged 3800 hot rod | garage queen
1997 Corvette | 55k | Silver Metallic | Z06 wheels | Date-night Hauler/Parts runner
2014 Town & Country Limited | Cashmere Pearl | 95k | Family Hauler
2002 Ram 1500 Quad Cab Sport | Black| 260k | Official Bonneville Hauler

Good and bad news. Got started on the supercharger oil change and was met with thick nearly gum like oil inside the supercharger that was a bitch to get out. I’m surprised it didn’t ever completely seize up with what I pulled out of there. I filled it up with new oil after cleaning out as best I could without removing the snout and put the belt back on. It sounds 100x better but still has a little drone to it. Plan to take the whole snout off soon to give it a deep clean and switch the coupler. Thanks a lot for the help once again. Got some Michelins on today now to take care of engine gaskets and the cv axle and this Bonnie should be in pretty *dang* good shape.

Doing gaskets today. Here’s how the rotors look in the charger.



https://imgur.com/a/QRRHEbi

Time for a whole new charger huh? I know the teflon wearing off is no good correct.

Rotors look great, coating is still intact. Normal for them to be dirty like that. There are no rotational score marks. Clean off a little of the grim. If they are shiny metal, that means the coating is gone. If they are gray, the teflon coating is there.

_________________
Andrew - owner/operator of Bonnevilles Unlimited

2004 Bonneville GXP | 60k | White Gold Tricoat | custom built supercharged 3800 hot rod | garage queen
1997 Corvette | 55k | Silver Metallic | Z06 wheels | Date-night Hauler/Parts runner
2014 Town & Country Limited | Cashmere Pearl | 95k | Family Hauler
2002 Ram 1500 Quad Cab Sport | Black| 260k | Official Bonneville Hauler

Appreciate the feedback.

Ran into the biggest issue yet today now though. Got LIM gasket and valve cover gaskets replaced today. Along with plenum gasket, coolant elbows, thermostat, temp sensor, and spark plugs. After finishing up the car will not start at all. It starts trying to crank but sounds pretty nasty. The only issue I know needs to be fixed for sure is the vacuum harness completely broke at the T under the supercharger going into the LIM. This obviously would cause issues running smoothly but this shouldn’t prevent the car from starting up fully should it? I’m afraid I may have a deeper issue even after tackling this.

Do you have spark? Are you sure the plug wires on correctly? Did you forgot the ground that bolts to the front head by the coolant elbows?

No, a little vacuum leak wouldn't cause a no-start.

_________________
Andrew - owner/operator of Bonnevilles Unlimited

2004 Bonneville GXP | 60k | White Gold Tricoat | custom built supercharged 3800 hot rod | garage queen
1997 Corvette | 55k | Silver Metallic | Z06 wheels | Date-night Hauler/Parts runner
2014 Town & Country Limited | Cashmere Pearl | 95k | Family Hauler
2002 Ram 1500 Quad Cab Sport | Black| 260k | Official Bonneville Hauler

Checked the wires and they correct. Got it to turn over this morning (didn’t try too hard last night because the crank noise was scaring me) but it sounds really rough at idle. Uploaded video to youtube and attached if you could let me know if it sounds like something direly wrong or if this could be standard ruptured vacuum line running. (Don’t have supercharger belt on yet) also haven’t been able to get coolant all the way into the system yet as I’ve only had the engine running as long as in the video.

https://youtu.be/OW4vdcXs-_A?si=sGBok6Ua7cSkrshS

You need to address the vacuum leak before any further diagnosing. It will probably take care of the issue as I can hear it whistling.

Best way to fill the cooling system is to remove the thermostat housing & thermostat and fill coolant at the radiator until it comes up to the level of the thermostat. Then install the thermostat and housing and continue to fill as much as it will take. Then start the car and it will suck a little down, fill to the top and install radiator cap. Then fill the overflow about 1" higher than the HOT line. After the first heat cycle where the thermostat opens and allows flow, it will suck the remaining coolant in the reservoir into the system as it cools down.

_________________
Andrew - owner/operator of Bonnevilles Unlimited

2004 Bonneville GXP | 60k | White Gold Tricoat | custom built supercharged 3800 hot rod | garage queen
1997 Corvette | 55k | Silver Metallic | Z06 wheels | Date-night Hauler/Parts runner
2014 Town & Country Limited | Cashmere Pearl | 95k | Family Hauler
2002 Ram 1500 Quad Cab Sport | Black| 260k | Official Bonneville Hauler

Update: found a massive coolant leak coming from right side of engine. I paid a mechanic to do the gaskets. Didn’t do it myself, he’s supposed to come back and fix it but not sure how much I trust him now. Do you have any idea what would be causing coolant to leak from (it appears) the LIM on the right side under the throttle body? I’d assume the LIM gasket. Lol. Trying to laugh through the pain right now. Hope there is no critical damage. Video attached you can hear how much coolant is hitting the ground and see some vapors burning off along with the path it was taking out at the end.

https://youtu.be/-GHcdjMVs08?si=qicsYfO9gSdqF5Le


Needless to say will not be turning this engine over again until this coolant and the vacuum leak are addressed.

Appreciate the info on filling it up. You have been extremely helpful. I overnighted a vacuum hose pack from ZZP but per my last update I have a bigger fish to fry than the vacuum leak now…