Just picked up a 95 and the performance is lack luster

Ok guys, I just picked up a 95 Riviera for my dad. When I drove the car I was very impressed with the way the trans shifts, but it is actually quite slow. I'm hoping it's due to the fact that it had sat for about a year, and we put some 87 octane gas in it from a pretty shady local gas station. When I bought the car the guy said the tensioner was going out, I pulled the belts (which were new) and spun the tensioner, no squeak. Spun the supercharger and checked the pulley for play, NONE. pulled the secondary belt, spun the accessories one by one, alternator pulley bobs up and down with a nice squeak squeak squeak, I think that's the culprit there. My question is where should I go from here? I've never dealt with these supercharged engine's before but I have done a TON of work on the N/A 3800's and various other motors over time. I keep reading about the boost solenoid and boost bypass valves, how can I verify these work? Or should I just do a basic tune including the charger oil and put good gas in it? It really sucks that GM decided to stiff us on a boost gauge in these cars, had it not boosted that wouldn't have scared me away, but I probably would have taken it home cheaper . Thanks in advance everyone, and kudo's on a VERY nice forum.

My advice is to start with a tune-up and go from there. Your problem could just be the fact that you filled up with crappy gas, being supercharged you will need to use premium always.

Ya when I bought mine it had bad gas in it and had been sitting. It ran so much better with fresh gas and stuff.

brian10962001 wrote:

Ok guys, I just picked up a 95 Riviera for my dad. When I drove the car I was very impressed with the way the trans shifts, but it is actually quite slow. I'm hoping it's due to the fact that it had sat for about a year, and we put some 87 octane gas in it from a pretty shady local gas station. When I bought the car the guy said the tensioner was going out, I pulled the belts (which were new) and spun the tensioner, no squeak. Spun the supercharger and checked the pulley for play, NONE. pulled the secondary belt, spun the accessories one by one, alternator pulley bobs up and down with a nice squeak squeak squeak, I think that's the culprit there. My question is where should I go from here? I've never dealt with these supercharged engine's before but I have done a TON of work on the N/A 3800's and various other motors over time. I keep reading about the boost solenoid and boost bypass valves, how can I verify these work? Or should I just do a basic tune including the charger oil and put good gas in it? It really sucks that GM decided to stiff us on a boost gauge in these cars, had it not boosted that wouldn't have scared me away, but I probably would have taken it home cheaper . Thanks in advance everyone, and kudo's on a VERY nice forum.

1) replace that alternator, you don't need the hassle and it's not all that pricey. When I replaced mine I bought an ACDelco reman from RockAuto.com. The Delco remans are awesome, what they do is break down old alternators and scavenge the hard components. So the case, rotor and stator might get re-used. But the bearings, brushes, rectifier are always new and the alternators are built and tested on same equipment to same specs as new, I am told. Details are here: http://www.acdelco.com/parts/alternators-starters/ By the way, the guy you bought it from probably just looked at the tensioner moving when the car was idling and may never have turned the pullies by hand. He probably saw the tensioner dancing. What he did not reckon, probably, is that the tensioner is not all that hard to replace, also not all that expensive if you buy it right (a Gates from say NAPA or RockAuto.Com) and gives you an excuse to replace the coolant elbow that's down there. Good catch.

2) by law all cars built in the US have to run on regular gas. However, they do not have to run well, a distinction that is lost on many people until they put a tank full of Regular in a car supposed to run on Premium. What happens, generally, is the knock sensor(s) pick up the knock from the regular gas and retard timing until it goes away -- which generally takes all the 'zip' out of driving. I suspect most don't make the association because if the car already had premium in it, it won't run poor immediately -- it depends on where the octane ended up after gassing up. If you had 3/4 tank of 93 premium and you top off with regular the octane probably won't go below 91 and you won't see any difference. If you had 1/4 tank of premium and you fill up with 87 regular the octane will go pretty low and your timing will retard after several miles (it will take a few miles to burn the fuel already in the lines/filter/etc. before the regular hits the fuel rail.

3) in general other than the blower and the parts you mentioned, it's a high-spec 3800 and you already know most of what you need to know. If you are careful you can hit the boost solenoid with backprobes connected to say a 12v lantern battery and listen for the click. I would not bother, though. As for the bypass valve, a MityVac draws more than enough vacuum to pull it, and if it is leaking it will leak down pretty quick. By the way, you get more boost if it is not working, but if it is not working it causes other, much more expensive problems. So you are better off if it is working.

4) if the transmission is mechanically sound you can get better performance by changing the fluid and filter - refill it with Dexron VI (the new fluid) though. People are deeply divided on whether to have it power flushed. I've had mine done and was happy. However, I think it's the case that the local dealer has a tech who really knows what he is doing. It is the case that if the tech does not know how to do the power flush right, it's a death sentence for the tranny because it can dislodge sludge and cause it to move from a benign to a fatal location. Given what I've heard about build quality on the Eaton transmissions (great trannies wiht uneven build hygiene) I wonder if one needs to do a flush and fill more than once or twice - second fill with Dex VI or synthetic Dex IV (Mobil makes one, AmsOil too) - then seal the sucker up and forget about it. I have it (power flush) done every 40-50 thousand miles.

5) yep, a tune-up would help. Fuel, oil and air filters, check plugs and wires, and if you can check/verify base timing (it should be fine). Also, if you knwo how, clean the throttle body. Most people don't. You know, if you start the car and it's idling, if the idle "hunts" at all (varies while idling) you definitely need to get a new TB gasket then pull the TB and clean it. If you use "search" function on this site you'll find good practical instructions for doing the cleaning. Also, if it looks like it's never been done you should consider replacing all the vacuum lines. If the PO missed the alternator odds are he/she missed vac leaks too IMHO, and there are not that many lines. The easy way to do this is drive it to an auto parts store and get the resident gearhead to look under the hood at the vac lines, tees and couplers. Buy a couple feet in each size the gearhead finds and get plugs and couplers (reducers) from the "HELP" blister packs. You probably won't need new tees BUT they have been known to get brittle under certain conditions so be sure and check. And you might also want to get a tube of the black RTV cement. Wha-La--You can now make up all the vac lines.

6) The other thing - on the cars with the 4T65E (you should have a 4T60 which is vac operated but you might not, you should check) you might want to disconnect the battery overnight and then drive gently for the next 25-50 miles after you hook it back up so the transmission can re-learn how to shift smoothly. I am not sure it would make a difference on the 4T60; on the 4T60 I'd think about a possible vacuum leak.

Albertj

Ok guys, the back glass was installed today! I finally got under the hood and started working. The old alternator wasn't as bad as I thought, I think it was just a bit rusty inside from sitting. I swapped it out and replaced the back belt. The front belt still squeaks but I think it's from the ghetto A/C bypass the old owner hacked onto the car.

I pulled the cover and found that the vac line for the trans was indeed pulled! I also found 1 rotten vac line which I replaced, and the vac line for the evap canister was unplugged. Finally the filter box was like something out of a nightmare!!! Rat nest, wasp nest, grains of rice, and the mice had eaten part of the filter, disgusting!!! I vacuumed that out and installed a new filter.

The car has been sitting with a dead battery (left the trunk open and didn't realize the light was on) and so the ECM was surely reset. Started the car up an took it around the block, all I can say is WOW. The car has throttle response now and you can feel that it has power.

The next step is the oil, and S/C oil change. I'm taking it to my mechanic once I get an AC compressor and hopefully that will cure the squeaking. I'm going to go spray them with some PB blaster while it runs to see which one it is for sure. I'll post up once I get to it.

You're making a lot of progress!!! Great to see many of your issues were solved with routine maintenance.

Agreed. Congrats on getting it back into shape! These cars were well engineered and should perform surprisingly well after you get all the kinks worked out!

Oil is drained, but my g/f drove off with the filter and the oil soooo, she's sitting out there draining still.

I bought synthetic Lucas, and 5w30 Mobil 1, but decided to wait on some supercharger oil. If anyone's curious as to why they say to run the specific oil, its because it's animal fat based oil. This is different in that it doesn't expand with heat. I think the M62's have extra room in them to handle this expansion, but since my dad is going to be driving this I decided it wasn't worth the risk.

The underside of this car looks unreal, very VERY clean. I did notice that one of the wheel sensors looks like it has broken wires hanging which is a negative, but I also found new sway bar end links so that makes up for it lol. I'll check on fixing the wires tomorrow once the oil is in.

Finally I aired up the tires, and crawled around the car looking for anything else that will need addressed. So far so good, I'll be driving it around a bit tomorrow so I'll know more then.

Sounds like you can expect the ABS/Trac light to be on... but at least you know which wheel bearing you'll have to replace to fix it!

I'm happy for you. This is a classic example of how important the basics are...

My 2 cents:
- Go to a parts store and by a "syringe with a little clear plastic tube" for sucking out the blower oil. I can't remember what brand it was, but it's perfect for sucking out the old oil from the bottom of the snout.
- Drive it down near empty and refill it with Premium (and be grateful that you don't have the 91-octane piss for Premium that we have here in La-la-land...)

Actually I bought a basic sprayer bottle from Wal Mart for 97 cents, all you do is slip the siphon tube into the blower hole and pump the oil out, 4oz won't take any time at all.

I do believe the brake light is on in the car, I think it's the only service light that was lit actually. I've helped my friend fix the wheel sensors a bunch of times on the newer style Blazers, usually there's enough wire left to splice them back together without buying a new sensor *crosses fingers*

The sensor on these cars is actually inside the wheel bearing, so if the wires aren't repairable, it's new wheel bearing time. Hope you can fix it, and again great job pulling this one back from the edge!

its amazing what a little maintenance will do

and dont forget, the 95 s/c can run with 50-50 mix of 5w30 and lucas oil stabilizer.or just plain 5w30.if you want to save a few bucks.

You may also want to get an A/C line filter to put ahead of your new compressor to catch any crud that may have been/formed in the system sitting empty all this time. While you are at it you must get a new reciever dryer (they are cheap) and you might want to spring for a new 'variable orifice' expansion valve (they are not that much $$ but they are way more $$ than the standard ones, which are darn near free) - do NOT let the mech put in a standard orifice valve, these systems used variable ones for a reason, because they run all the time, variable orifice reduced the work the AC has to do. Also with the variable orifice valve the system should run relatively quietly. Probably cheapest to order them all from RockAuto.Com, prices of different 'brands' are about the same so to save $$ just be careful to try to get them from *the same shipping location.*

Albertj

Any way I can get some links to these parts? I already looked up the dryer and plan to have it changed. The compressor is sitting in the box ready to go. I've been waiting on the rear shock parts to come in before I drop it off to have the AC done.

brian10962001 wrote:

Any way I can get some links to these parts? I already looked up the dryer and plan to have it changed. The compressor is sitting in the box ready to go. I've been waiting on the rear shock parts to come in before I drop it off to have the AC done.

they are **All** in the A/C parts listing on rockauto.com, and my local NAPA had them too, you might want to try yours after looking parts up on rockauto.com.

Albertj

Got the car back yesterday, ICE cold AC sure is nice, it's about 90 degrees and humid here. The rear shocks are still on back order and I'm about to say forget it and just get my money back. The car is just about sorted out, the only big problem I'm still having is the belt squealing (more like screaming). It's the alternator belt not the SC belt and I'm not sure what else to do about it. It seemed to be quieted down when I dropped it off and now that I have it back it's louder than ever.

sounds like you have a bad belt tensioner or a ilder pully bad and you always want to replace the belt whenever you replace a pully, once you do that you shouldn't have any more squeeling .

Quote :

The car is just about sorted out, the only big problem I'm still having is the belt squealing (more like screaming). It's the alternator belt not the SC belt and I'm not sure what else to do about it.

I thought the Series I supercharged engine only had one belt?

You need to hunt down the source of this noise and replace the bad pulley or accessory, and/or the belt (squealing/screaming isn't good). Don't rule out the alternator, water pump, power steering pump, or the blower itself. All of these use bearings and can fail, although I agree it's more likely a tensioner/idler pulley. If you let this go, you'll be stranded when it finally fails. Good luck!

AA wrote:

I thought the Series I supercharged engine only had one belt?

2 belts, just slightly different things on each then the series 2.

brian10962001 wrote:

Got the car back yesterday, ICE cold AC sure is nice, it's about 90 degrees and humid here. The rear shocks are still on back order and I'm about to say forget it and just get my money back. The car is just about sorted out, the only big problem I'm still having is the belt squealing (more like screaming). It's the alternator belt not the SC belt and I'm not sure what else to do about it. It seemed to be quieted down when I dropped it off and now that I have it back it's louder than ever.

I am surprised that getting the rear shocks is such a pain. They are used on a number of GM cars, should not be a big deal. You might even get a junkyard pair to put on temporarily.

Albertj

brian10962001 wrote:

Got the car back yesterday, ICE cold AC sure is nice, it's about 90 degrees and humid here. The rear shocks are still on back order and I'm about to say forget it and just get my money back. The car is just about sorted out, the only big problem I'm still having is the belt squealing (more like screaming). It's the alternator belt not the SC belt and I'm not sure what else to do about it. It seemed to be quieted down when I dropped it off and now that I have it back it's louder than ever.

A shop fixed your AC and returned the car to you with a belt screaming so loud that you don't want to drive it.
Who do you have fix your car and why don't you bring it back and ask WTF is up with this noise.
As far as the air shocks, have just tried your local auto parts store for some Monroe Replacements.
None of this is rocket science.

Well Rick since it's pretty apparent you just jumped into this thread with smart ass comments instead of actually looking at my other posts I'll bring you up to speed. I already ordered the Monroe shock conversion kit for the rear, it's on backorder so your smart ass "rocket science" comment is pretty ignorant. The belt has been squealing since I bought the car and I thought it was the series 2 ac delete pulley the previous owner had installed, it wasn't. It's the back belt squealing so I was incorrect and the compressor didn't fix the issue. I would have done the AC myself but I don't have the equipment to vac the lines. I already purchased a metal replacement alternator tensioner pulley and would have put it on today if it weren't raining so hard here.

Well Brian Tucker,
Based on what I read I stand by my statements and add that if any of the 2 shops that I do business with were to get my car in for an AC repair, as yours was, and the belt or tensioner was squealing as bad as you said it was, they would have called me to tell me something else was wrong. You did not mention you had a new tensioner ready to install.
Regarding the Monroe replacement shocks for these cars, they are available at many different supply houses and if it were an issue to you, I would be looking for who does have them in stock and not waiting for a back order that obviously has you distressed.
I guess that's what I should have written in the first place.
Rick