2003 Supercharger Help

bigsky

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03 PAU 202k, 04 PAU 90k, 97 PA (salvage 185k), 99 PA (sold-now 170k), 2K PA (sold-now over 200k).
Ok...couple things going on with a 2003 PAU with 202k miles.

Was headed up a hill in MT today; give her some gas, car downshifts to 3rd and over the mountain we go no problem for the supercharged engine. That is how it normally works...

Today...downshifts to 3rd and stumble...stumble...no power... bucking...make it (barely) over the hill at about 40MPH. GREAT...Tranny maybe...?

Got home removed the supercharger belt and the car runs & shifts fine ...so...must be a problem with the supercharger.

The snout pulley has a "little" play; could it be the coupler? The car has been noisy for about a minute after startup, and I read that could be a sign of the coupler going bad.

Maybe the valve bypass? The round canister looking thing? I know when my boost solenoid went out on another car it did not do this.

Is my supercharger gone?

Went looking for codes & discovered a P0131 Oxygen Sensor code (no check engine light was on). Scanner said "passed & failed." Recently replaced the Fuel Pump, filter, & Fuel Pressure Regulator so I just cleared the code and will see. Maybe will replace the front oxygen sensor if it comes back.

Since the car runs "ok" without the supercharger belt, the 131 is probably a different problem...(?)

Any advice on the supercharger issue...?
 
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Gluttenforpunishment

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Well, I doubt your supercharger is blown, there is not much to them. BuickGirlfromMars will chime in later today to give you the full skinny. It more than likely needs a service, most superchargers that I know of simply need their oil and o-rings changed out when issues arise. The play you mentioned, no clue, but I would assume a simple fix if parts are available. Honestly, there is nothing to these things.

I found this from our girl...

"91 octane should be used simply because it was made to run with this. Servicing the supercharger has two things, coupler and fluid. You can do both if you replace the coupler, which is likely in the near future of the car anyway, or you can start with just the fluid. Only use gm supercharger fluid, which I say because it’s affordable. Motor raft and Eaton brand fluid is the same, but more expensive. If you google the procedure it’s quite easy with a spray bottle head and adequate fluid to do the job."




Found this...

P0131

Description

HO2S 1 CIRCUIT LOW VOLTAGE

PCM provides about 0.35 volt reference to HO2S 1. HO2S 1
sensor signal voltage varies from about one volt when exhaust is rich
to about 0.1 volt when exhaust is lean. PCM reads and stores sensor
voltage information and evaluates the voltage samples to determine
amount of time sensor voltage is out of range. If HO2S 1 voltage is
out of predetermined range, DTC will set.

Symptoms
There may be no visible symptoms to the driver, other than the MIL (Service Engine Soon).

Causes
  • Faulty o2 oxygen sensor
  • Short to voltage on O2 signal circuit
  • High resistance or open on O2 signal circuit
Solutions

The P0131, if you replace the O2 sensor, only use an ACDelco unit, no other brand will work properly on our PAs, hope this helps, and eases your mind.
 

Goodie4Goose

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2002 Park Avenue Ultra 61K miles. First car was a 1989 Buick Century, aptly named the Blue Demon.
It is worth noting that the needle bearings for the impellers can be replaced as well. I have no experience in doing so, but I came across the process while researching the service procedures for the M90 a couple months back. I think it is only necessary to do so if your impellers are out of alignment, which would be evident from noticeable wear of the Teflon coating. You may also hear the bearings grinding when you spin it by hand. Again, I haven't performed the service, I'm just ad-libbing what I remember.



Of course, if the coating is worn considerably, it is probably due for a new set of impellers, if you can find them. I haven't a clue if they can be recoated nor where one could have it done. Dow Chemical maybe? I do know that the charger will lose its pull as the coating wears. Something to keep an eye on if you suspect your spinarooni is tapping out.



I'd also check your gasket where it mounts to the lower intake. If it is leaking, even a little, you will lose boost, though I'm sure it'll be more than a "little" leak. Then there's the common manifold gasket leaks to consider as well. I recently changed the gaskets on the top & noticed immediately an impressive gain in power.



Anywhore, I hope you pin down the issue & I hope it's an easy fix.




Goose
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bigsky

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03 PAU 202k, 04 PAU 90k, 97 PA (salvage 185k), 99 PA (sold-now 170k), 2K PA (sold-now over 200k).
Ordered a new ACDelco oxygen sensor.

I am thinking the belt may be slipping on the supercharger. The SC tensioner has nowhere near the spring tension that the drive tensioner has.
 

bigsky

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03 PAU 202k, 04 PAU 90k, 97 PA (salvage 185k), 99 PA (sold-now 170k), 2K PA (sold-now over 200k).
Still working on this...& appreciate the responses so far.

As mentioned, I took the supercharger belt off and the car runs fine, and is not throwing the P0131 code.

The problem that occurred is more than a little glitch...it is major. When boost kicked in the entire engine was shutting down...try to give it more gas and the engine almost dies. Severe drivability issues...like the car is getting no gas! Major problem!

I have a question and a theory. Could a flaky/bad oxygen sensor cause such major issues when boost kicks in...and throw the P0131 code? The sensor seems to be operating fine with no supercharger.

This raises the question, could the MAF go bad when boost kicks in; the symptoms are similar to what I once experienced with a bad MAF (but that happened even when not in boost).

I am just questioning and theorizing. New oxygen sensor has been ordered, I can clean or swap the MAF out, and also have a new SC tensioner on the way (in case the belt is slipping).

I am tempted to just run without the belt, and switch to cheaper regular gas, but boy that boost is nice to have, especially in the hills & mountains of Western MT.
 

HotZ28

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Have you considered the MAP sensor being faulty?
Exactly what I was thinking!!! If a map sensor fails, it can cause the PCM to miscalculate the amount of fuel and ignition timing needed for proper engine performance. this will cause the engine to run poorly and lose power. turbo and supercharged engines will suffer even more due to their reliance on the map sensor for a boost in fueling and timing needs. Be sure to check the vacuum line from the LIM (below the S/C snout) to the MAP sensor first & if that is all OK, suspect the MAP sensor itself. Some testing can be done if you want to following the advice in the links below.

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Gluttenforpunishment

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I just bought a new MAP sensor today up at Oreily's when I discovered the one on my motor was a cheap knock off. I found the correct ACDelco unit, roughly $90, you can get the same part a bit cheaper on the internet... It is part #19418808. According to the GM parts website, this works on both the Base and Ultra models.
 

bigsky

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03 PAU 202k, 04 PAU 90k, 97 PA (salvage 185k), 99 PA (sold-now 170k), 2K PA (sold-now over 200k).
Thanks for the help.

So... I put the SC belt back on today & everything is running fine with the SC.

"Something" glitched. Will run for a while & see if it happens again (and carry the belt removal tool with me).

I did have that O2 code (P0131), and have a new ACDelco front sensor on the way. Thanks for the tip & info on the MAP sensor. It is possible both of these sensors are original.
 
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HotZ28

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I just bought a new MAP sensor today up at Oreily's when I discovered the one on my motor was a cheap knock off. I found the correct ACDelco unit, roughly $90, you can get the same part a bit cheaper on the internet... It is part #19418808. According to the GM parts website, this works on both the Base and Ultra models.
MAP sensors are not the same between the base & Ultra models. The are completely different animals in how they monitor, fit & connect to the vacuum.

The Ultra MAP sensor:

The Base MAP sensor:
 

Gluttenforpunishment

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MAP sensors are not the same between the base & Ultra models. The are completely different animals in how they monitor, fit & connect to the vacuum.

The Ultra MAP sensor:

The Base MAP sensor:

Just going off the GM parts site, it stated compatible with both motors... Everyone should do their own due diligence. Thank you for the correction. ;-)
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HotZ28

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Thanks for the help.

So... I put the SC belt back on today & everything is running fine with the SC.

"Something" glitched. Will run for a while & see if it happens again (and carry the belt removal tool with me).

I did have that O2 code (P0131), and have a new ACDelco front sensor on the way. Thanks for the tip & info on the MAP sensor. It is possible both of these sensors are original.
Have you taken the car for a ride under full boost yet?
 

bigsky

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03 PAU 202k, 04 PAU 90k, 97 PA (salvage 185k), 99 PA (sold-now 170k), 2K PA (sold-now over 200k).
Have you taken the car for a ride under full boost yet?
50 mile highway run today, with hills, and no stumbling or problems when the car downshifted to 3rd and went into boost. I pushed it a little and everything seemed back to normal.

I am just going to run it as is for now, and see if it happens again. With 202k on the motor, I suppose any sensor could go flaky. The tranny was replaced at 110k said the previous owner when I bought the car at 120k. The tranny has always shifted great.

When I bought the car, I had the MAF act up so I replaced. The car was bucking at low speeds and NO CODE was set...so I figure bad sensors don't always throw codes.

A month ago, every now & then I was getting a hard start, so I had the fuel pump replaced (new ACDelco) and fuel filter. Had another slow start so I put on a new ACD Fuel Pressure Regulator. Getting ready for plugs & wires.

The way this problem happened seems more than needing tune-up items. There was a major glitch somewhere. When the car went into boost on the hill, giving it gas caused surging (I thought it was the transmission slipping); giving it more gas just wanted to stall the engine. I could still drive the car just needed to stay out of boost.
 
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bigsky

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03 PAU 202k, 04 PAU 90k, 97 PA (salvage 185k), 99 PA (sold-now 170k), 2K PA (sold-now over 200k).
When a car hits this age & mileage, decisions have to be made. This is the first car I have ever owned with 200k.

The question always is,,, how much money do I want to put in? I know some people have done many more miles than 200k on PA's & LeSabre's.

The lower doors are starting to rust out from the bottom. Anything can go wrong, even on newer cars. I had a brake line blow out coming down a hill (only going about 30mph) in a 1989 Old's 88 with a lot less miles. I was able to swerve into the dich to avoid hitting the car in front of me. He must have thought: who is this "impatient guy" passing me in the ditch?!

I like the car enough to put some money in; don't know how far I'll go. I had a chance a couple of months ago to get an 04 Ultra with only 100k for 5k. I talked myself out of it because I also have an 04 Ultra which is the garage queen for the winter.

I figure (hope) maybe this 03 can get 225k (or more). The 04 that was for sale would need all the 100k work, including those lower intake gaskets, and I am not confident/experienced enough to do those myself. I could call it a learner project, but then I need to tie up garage space and I have a full-time job (but a bachelor), so how backed up does a guy want to be..! Having a wife and/or family and the whole thing would be even farther away from reality.

I am not thrilled with what to purchase from here. The Chrysler 300 seems kind of close, but I have never sat in one or driven one. SUV became the norm...maybe...maybe not...and the new stuff gets problems as well.

PAU...for 300k please...
 
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Gluttenforpunishment

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I would not be too quick to jump into any older Chrysler product, learned that the hard way. Cash for Clunkers wiped out many of these older Chryslers according to the many folks I spoke with across the country when trying to source parts for one I owned. These Buicks we drive have superb parts availability when compared to any older Chrysler product. I was shocked to say the least, but it is understandable, when there are few if any of those models on the road, the support is simply not going to be there.
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BuickGirlFromMars

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My list of checks:
Supercharger belt condition, tensioner condition, idler (for SC belt) condition, coupler of SC condition, fluid status, bypass adjustment and rod actuation condition, PCV and the baffle underneath it and the spring/o ring seal necessary there, and the vacuum hose harness condition. I would also block the vac lines to the purge valve and then remove the purge valve connector.
If all that checked out, and issue persisted, I Would be surprised. To me it sounds like you have a slipping belt. boost is causing your car to have inconsistent power which falls on its face when you dont have your expected boost.
 

TX LaCrosse

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If your blower belt is indeed slipping, ZZP makes a belt wrap kit to remedy that issue.
 

HotZ28

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If your blower belt is indeed slipping, ZZP makes a belt wrap kit to remedy that issue.
I don't recall bigsky the OP, mentioning running an intercooler or smaller S/C pulley then the original??

"This belt wrap kit eliminates concerns of belt slip often experienced when running smaller pulleys. We accomplish this by adding an additional "floating" pulley which forces the belt to wrap around more of the supercharger pulley, significantly reducing or eliminating belt slip. This is intended to be used with intercooled setups."
 
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bigsky

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03 PAU 202k, 04 PAU 90k, 97 PA (salvage 185k), 99 PA (sold-now 170k), 2K PA (sold-now over 200k).
To Update: Replaced both belts , the SC tensioner, and the main drive tensioner pulley which was making a grinding noise (the other pulleys seemed ok). The Gates belts & Dayco pulley had 80k on them, the tensioner was probably original.

Both belts were stretched according to the tensioner marks.

Everything seems OK, and the O2 sensor code has not come back. Will run like this for a while and see how it goes. Thanks for all the help.
 
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