Newbe

[garrett]

I am the new onwer of a 95 Riviera 3800 supercharged Buick. I am very familiar with the turbo Buicks of the eightys, but this car is a bit different. I need some help diagnosing some problems. I bought the car last night, and drove it home. I noticed that the car has almost no power. It has 260000 miles on it. Almost all the miles are highway miles since the previous owner was in sales and his job required him to drive long distances on the freeways. He said he changed the oil every 3500 miles. The car doesn't leak oil or burn oil. There is no smoke coming from the tailpipe even while driving and accelerating. I think there is nothing wrong with the internals of the engine. The supercharger was replaced 4 years ago.

Here is what I'm going to try in order to get this car to perform:

Fuel injector cleaner- incase the injectors are clogged
New plugs and wires- Last changed over 150000 miles ago
removing the catalytic converter- may be plugged (260000) miles

My questions are: Does this car have a port to plug a code reader into like my Grand National? If I replace the catalytic converter with a test pipe, will it throw a code?
Before someone gets on there environmental high horse, I know that this is illegal, I would only do this for test purposes

[Torque Overhaul]

Consider replacing the fuel filter. I would also recommend replacing the S/C oil, most never change it, or are not familar with changing it. This will help pro long the life of the bearings and coupler in the snout.

For plugs-Autolite 605 copper plug's are a popular choice gapped around .55-.60 and work very well.

On your wires don't waste money on MSD most vehicles have issues with them the GM ingnition on these car's acts funny with them. Not to mention the coil packs are worse(multiple problems at least in the GP communtiy). As far as bang for the buck quality, I would suggest a set of Taylor or PRJ wires.

I would highly recommend the LIM gasket be replaced if it was not done by the previous owner- Look around the fuel injectors, over time you will begin seeing coolant puddling up.

I would also suggest getting some carb cleaner, starting the car, and spraying all vac lines to see if you have any leaks.

New O2 sensor's should help as well if they have been on for awhile.

Get some MAF cleaner and spray the MAF really good. You would be surprised how much differnece it can make if it's never been done.






It's more than likely OBD1 and I believe it's under the hood on the firewall by the driver side. If it's a late model 95 it's very possible it's an OB2 and it would be located under the dash on the driver side near your right knee.

I know on the GP's a catless dp will throw a code. However the way we get around that is by deleting the code from the PCM, using a h/flo cat, or snipping the O2 wire off the O2 sensor and plugging it back into the car's wiring harness. Although the last one may not work for you.


If you have any more question's please feel free to ask. I've enjoyed my GTP and have tweaked on it more times than I can count.

[garrett]

I didn't think of the O2 sensor and Fuel filter, but I will do both. As for plugs, I was going to go with the new E3 plugs. I will replace the spark plug wires with Taylor wires. There is no coolant puddling anywhere on the engine. The car is a early 95, purchased in late 94, therefore probably has the earlier ECM port.

[garrett]

I went to the RegalGS.org website and did some research. It seems that a clogged Cat is a common problem with these cars when they get over 200,000 miles on them. Especially one like mine that wasn't properly maintained. Once I do the tune up, and replace the ATS sensor plug that was chopped off at some point, do you recommend that I gut the cat, replace with a straight pipe, or replace with a high flow aftermarket on from Summit. I don't want it to be loud, stinky, throwing codes, etc... I bought the car for my wife. I also don't want to spend the kind of money OEM parts usually cost.

[murphinator]

you may want to join the riviera forum. where you have a 95 it is a series 1 engine with an m62 supercharger

I think I welcomed you in your welcome thread on the regal forum ! 99% of people on that forum are series 2 & 3 owners as well as on club gp

I bet there are more series 1 guys there or on the bonneville forum maybe that will be more intimately intune with your mechanicals

as for your cat code zzp sells an 02 "spoof" for around $30 that should cure that and since you just bought it doing all the routine maintenance listed by the poster above may cure its issues and should be done along with a trans service anyways

[garrett]

So I guess since my car was made in 94 and sold as a 95 model year, then it only has one O2 sensor?

[Torque Overhaul]

Originally Posted by garrett

I went to the RegalGS.org website and did some research. It seems that a clogged Cat is a common problem with these cars when they get over 200,000 miles on them. Especially one like mine that wasn't properly maintained. Once I do the tune up, and replace the ATS sensor plug that was chopped off at some point, do you recommend that I gut the cat, replace with a straight pipe, or replace with a high flow aftermarket on from Summit. I don't want it to be loud, stinky, throwing codes, etc... I bought the car for my wife. I also don't want to spend the kind of money OEM parts usually cost.

From what I have seen and read about I would get a straight pipe as long as emissions isn't strict where you leave. There's nothing more than a PITA than to have to drive around trying to find someone to pass you. I purchased a dp with a high flo cat on mine, and it worked out just fine(Tx emissions). It's possible there's only one 02 sensor, but I would think there's 2. One at the top of the rear manifold then the other will be directly after the cat. If the ubend is there the 02 sensor will be sticking straight up towards the floorboard of the car. Let us know what you find out. I know the Regals are comfortable as hell to ride in compared to my GTP. How's the ride in the Riv?

[garrett]

There is no such thing as emissions testing in Florida.

[garrett]

I tried to post on the RegalGS website inquiring if anyone has tried the E3 plugs in their 3800 engine. It's been two days and nobody responded. I guess things move very slow on that site. So has anyone tried them in their car? Do they work better than the other standard plugs?

[Torque Overhaul]

Originally Posted by garrett

I tried to post on the RegalGS website inquiring if anyone has tried the E3 plugs in their 3800 engine. It's been two days and nobody responded. I guess things move very slow on that site. So has anyone tried them in their car? Do they work better than the other standard plugs?

Didn't they just come out? They got bashed on the GP boards. here's a link to the thread talking about them.
ClubGP Message Forum troubleshooting

[garrett]

I guess I will go for the cheap Autolite 104. I always thought autolites were for Fords. Has anyone tried the Iridium plugs?