I have a 1994 Oldsmobile cutlass ciera 3.1 v6 with about 115,000 miles on it. My engine will violently rev itself and I have to increase the rpm and slowly idle it down myself to get it to stop. When it does stop revving it runs rough. I took the serpentine belt off and it ran like a top. The alternator has a slight squeak when I turn it with my hand. All the other pulleys are fine. Could this be another electrical issue or do you think the alternator bearing maybe going out. Alternator was recently replaced and is a remanufacture.
The alternator has a slight squeak when I turn it with my hand. All the other pulleys are fine. Could this be another electrical issue or do you think the alternator bearing maybe going out. Alternator was recently replaced and is a remanufacture.
The alternator should spin easily and freely, it shouldn't squeak, replace it.
It spins freely and the squeak is very light. Maybe it gets worse with all the pressure of the belt on it? Doesn’t make a squeak while running but makes a hissing sound. I just want to make absolutely sure it’s the alternator because a good quality new one is $100
Your alternator is designed to be run by a belt. It should not be 'singing' under load. Remanufactured electrical parts generally aren't a wise choice because they're typically a mixture of new parts combined with "still good" parts.
I just want to make absolutely sure it’s the alternator because a good quality new one is $100
If a good-quality new alternator for that car is only $100 I would have bought that in the first place. Rebuilt alternators can be a real crap-shoot.
It was my mom who bought it to surprise me because the old one was dimming the lights. She don’t know much about parts. I plan on getting the new ac delco one from Rockauto
It spins freely and the squeak is very light. Maybe it gets worse with all the pressure of the belt on it? Doesn’t make a squeak while running but makes a hissing sound.
If it squeaks in your hand, when you've got the serpentine belt on, it's under probably 10-20x more pressure when the engine runs, if not even more than that. You need a big lever to push on, in order to relieve pressure on the alternator. You need to take the slack yourself so you can unbolt it. That same pressure was originally on the alternator.
Just got the alternator on today and it did not fix the issue.
Does the new alternator squeak?
No, but it makes a whining noise that wasn’t there before I replaced it. I didn’t expect a brand new alternator to do that. I didn’t damage it in any way.
These are the kinds of things you run into dealing with a 30-year-old car, blind alleys and cascading problems.
If you measure the alternator voltage and it's OK there should not be anything there to upset the computer. (It would be nice to test for excess ripple as well, but that's not likely a problem on a new unit.)
The car is too old for OBD2 diagnostics, but are there any OBD1 codes? (I assume you do not have access to a TECH2 or other scan tool that will work with that car.) Is the IAC valve operating properly? Any leaky hoses connected to it? Throttle position sensor working OK? Any corroded wiring or connectors, or bad grounds?
You may also want to look through the shop manual for that car for troubleshooting information, particularly the "Powertrain Management" section.
The engine still revs and now stalls at times completely shutting off. I think they sold me a faulty
I don't see how an alternator would cause violent revving. But you can always get it tested.
I ordered a mass air flow sensor anyway because I think I accidentally hit it with throttle body cleaner.
TB cleaner shouldn't hurt it. Did you verify the MAF sensor values?
continually shooting parts at this won't solve your problem.
No, but it makes a whining noise that wasn’t there before I replaced it. I didn’t expect a brand new alternator to do that. I didn’t damage it in any way.
No, but it makes a whining noise that wasn’t there before I replaced it. I didn’t expect a brand new alternator to do that. I didn’t damage it in any way.
So check the other pulleys with the engine running. Use a mechanic's stethoscope to pinpoint where the noise is coming from. If it's a worn power steering pump, the pump will whine as you move the wheel back and forth, for example.
The idle air control valve is new. No vacuum leaks I can find. My engine light burned out so I can’t read codes. Throttle position sensor is new. I’ve reset the computer a few times. And when I take off the serpentine belt it runs fine. Should I replace the tensioner?
If the tensioner is bouncing around a lot it is probably weak so not a bad idea. Remember that new parts are not necessarily good parts, especially if they are aftermarket items - but even OEM can be defective. The really odd part of the problem is that it runs OK with the serpentine belt removed. The only electrical component there that I know of would be the alternator.
You should replace the check engine light. It's possible there's an OBD1 error code. Also look through troubleshooting information in the shop manual.
I just ran it with the belt off again and it’s now doing it with it off. Mass air flow sensor maybe?
The whining does not change when I turn the wheel. I know it’s coming from the alternator because I can pinpoint it to it. Water pump is new. Compressor was removed and replaced with a bypass pulley which is still solid and turning freely. Power steering works fine. Tensioner bounces a lot.
I just ran it with the belt off again and it’s now doing it with it off. Mass air flow sensor maybe?
That's not a typical symptom of MAF failure, quite the opposite. With a bad MAF the engine would be stumbling and stalling.
Don't guess and throw parts at it, you need to troubleshoot the problem.
I just ran it with the belt off again and it’s now doing it with it off. Mass air flow sensor maybe?
Are you saying your 2nd alternator whines too? Or is the engine still reeving..
The engine still revs and now stalls at times completely shutting off. I think they sold me a faulty alternator so that’s a separate problem I have to deal with now. I’ll just put the old one back on until I can replace it again. It’s very hard to get customer service with Rockauto. I ordered a mass air flow sensor anyway because I think I accidentally hit it with throttle body cleaner.
I think they sold me a faulty alternator
Did you determine that by testing it?
It’s very hard to get customer service with Rockauto.
That can be a downside of buying from them, it's a tradeoff for the low prices.
I ordered a mass air flow sensor anyway because I think I accidentally hit it with throttle body cleaner.
Hopefully an OEM replacement. Aftermarket sensors frequently don't work properly.
I know alternators are not supposed to whine really loud. It only started whining when I put it on and it comes from the alternator.
Waiting on a MAF sensor should be here the 13th. Don’t know what else it could be.
Waiting on a MAF sensor should be here the 13th. Don’t know what else it could be.
Let us know how you make out, but as I mentioned previously a bad MAF sensor usually has the opposite effect, and as @imperator said it may not have been damaged by a little TB cleaner. You should have tested the sensor before ordering a replacement. Assuming that doesn't fix the problem, to find out what else it could be you need to do more troubleshooting, maybe even replace that burned-out check engine light (assuming the bulb is at fault) to see if there are any OBD1 codes that could provide a clue. As @imperator says, you're not going to get very far guessing and throwing parts at the problem.
Other than that you're going to need to find a mechanic with a Tech2 or equivalent scan tool that can work with GM OBD1. Unfortunately many mechanics these days will not touch a pre-OBD2 vehicle.
By revving I mean the rpms go really high then drop very low and keeps doing that until it manually control the throttle, put it in gear, or it dies. It stops revving when I put it in gear.
I replaced my intake manifold gaskets because it had just about all the symptoms for it. Got it back together and waited 24 hours for the rtv to set then started it up and it ran worse than before. It started sputtering and revving and had a cloud of white smoke in the shop. I’m going to replace the head gaskets soon. I have them I just didn’t want to mess with the exhaust manifolds.
I’m going to replace the head gaskets soon. I have them I just didn’t want to mess with the exhaust manifolds.
If there is sufficient clearance you can disconnect the header pipe and remove the head with the exhaust manifold attached. One of the worst parts of doing a head gasket job is wrestling with rusted exhaust manifold bolts which are virtually guaranteed to break.
If that's not feasible there are quite a few videos on youtube showing various tricks to get those stupid things loose and how to remove the broken bits when the worst happens.
I’m hoping I can reuse the new intake manifold gaskets I put on. The upper gasket is cork and the lower is plenum.
I’m hoping I can reuse the new intake manifold gaskets I put on. The upper gasket is cork and the lower is plenum.
Here's Uncle Tony's take on the subject of gasket re-use. He basically says you need to do some prep when installing paper or cork gaskets in order to have a shot at success using them more than once:
https://www.youtube.com/watch?v=x7lAWmdLU_0
I replaced the head gaskets and did everything correctly and it’s running the same except for gas coming out of the tail pipe and smoke coming from below the spark plugs on both sides of the engine. I’ve parked it for now and I’m done with it unless anyone has any ideas. I’m thinking of putting a different engine in it.
dang dude that just sucks all around