Metallic Squealing Under The Hood

[RX in NC]

I happened to be outside with our dogs this morning when my wife started her RX to leave for her office. Immediately upon ignition there was a significant metallic-sounding squealing coming from the engine compartment. This lasted approximately 5 to 10 seconds, then the normal sound of the engine running was all you could hear. By the time I hustled over to the vehicle and motioned for her to pop the hood, everything was back to normal.

This was not worn-out belt noise; in fact, I changed the AC/Alternator belt (using the OEM Toyota part) back in late May and the belts have been whisper-quiet again ever since. This sounded more like bearings squealing, and I'm guessing that perhaps it could be the bearings in the crankshaft pulley. Of course there's also an alternator, an A/C compressor, and a power steering pump that are driven by the two belts on this vehicle and all the pulleys associated with those devices would have bearings as well. But just judging from the loud, deep, and lengthy duration of the squealing I heard this morning, my best guess is the crankshaft pulley.

Anyone else out there been through this issue? If so, did you attempt the fix yourself or elect to pay someone else to do it? And how much did it cost you for the repair? My biggest concern in attempting to find and fix the problem myself is the fact that there is simply no working room down in this area of the engine compartment. It was difficult enough for my buddy and me to remove and replace the AC/Alternator belt back in May due to the limited room. I think that trying to remove both belts along with the crankcase pulley in order to get to any failing bearings will be extremely difficult.

Any responses from those of you who've dealt with a similar issue will be very much appreciated. If my problem is in fact a set of dying bearings, this issue must be addressed as soon as possible before any serious damage is done.

[bluestu]

I had that problem last winter when I went out to start my car. My car started making the squealing noise like yours. I thought it was a belt, so I went back inside. When I came back out, my car was pouring out smoke and the cabin was completely filled. I turned the car off and it wouldn't start back up. I suspected that the starter had burned up and it had. I replaced the starter and everything has been fine since, although it took several weeks to get rid of the smoke smell. I think what had happened was the gear on the starter had gotten so worn that it couldn't engage with the crankshaft and just got stuck inside the shaft upon ignition. Prior to this incident, I had heard that horrible noise briefly before at startup.

[RX in NC]

Thanks for your reply. I did not suspect the starter, but that's another possibility. I'll keep your situation in mind as I investigate our problem a little further.

Did you source your new starter from a Lexus parts department, a Toyota parts department, or an independent parts provider and what did you pay for it? Also, was it new or rebuilt?

I appreciate your feedback as I attempt to get to the bottom of this issue. It sure sounded like worn bearings to me, but being an intermittent problem I really don't know at this point. I want to nail it down before I start sourcing parts, though.

[bluestu]

I purchased a rebuilt starter from a foreign car parts store in my town. I know them well and they always help me out if there is a problem with any parts I buy. I paid less than $200.00, but they gave me a discount so I don't really know what the actual retail price was. The only problem was the wire plugs weren't in the same place as the original so I had to splice one of the wires to make it longer. Prior to the starter burning up, I was having trouble starting my car for several months. At first I thought it was the battery because there was just a click when I would turn the key. After a few trys it would always start. I then figured there was a problem with the ignition switch. After I took the old starter out, I noticed that the gear teeth were slightly worn down and the shaft was partially engaged and totally frozen. I suspect there was a mechanical problem with the gear shaft and not the gear teeth. The ignition switch seems to be fine.

[TunedRX300]

www.rockauto.com has rebuilt oe starter for $142, plus core deposit and shipping. No tax, and you can google 5% discount code on the net. Bought many parts from them, great prices.

[RX in NC]

Great info from both of you - thanks again. I'll continue to check her vehicle and keep you posted on what I learn. After talking with a Toyota technician this afternoon, I now believe that the starter is the most likely culprit.

[RX in NC]

The vehicle is home now and I've spent the last ten minutes attempting to get it to squeal again. No luck.

My wife says that she's heard squealing noises (although not nearly as bad as what we heard this morning) when either starting the engine with the A/C already turned on, or turning on the A/C when the engine is already running. When she then turned off the A/C with the engine still running, the squealing noises immediately ceased.

If her description above is accurate, the guilty component would probably be the compressor. Unfortunately, a compressor problem will be three times as costly to repair as a starter problem, if not more. I'd certainly rather deal with a failing starter.

I'll continue to experiment with the vehicle and keep you posted. Perhaps the initial cold start of the day will be my best chance to recreate the problem, so I'll be outside bright and early tomorrow morning with the hood open when my wife first turns the key.

If you have any more suggestions or input, please contribute to this thread. Thanks.

[SKperformance]

My LS used to make a horendous squeel every single morning.It only happened when started for the first time of the day never after.

It was because the alternator on my car was struggleing to load back up the battery. Once i replaced the belt i found it not glazed and only slightly cracked ,meaning i could see them but not get even a sheet of paper in it.

I also never heard it unless i opened the door and would hear it.

I got a new serpentine belt and it is gone now.

I still have to find the culprit for the discharge overnight which may be old battery grounds.

Not sure if it is anything like yours but it didn;t sound like any normal belt naoise i had heard before.

[RX in NC]

This morning I was outside waiting with the hood open when my wife came out to leave. Last night I ensured that the A/C was switched off so the compressor would not be running when she turned the key this morning.

She cranked the key and the engine started smoothly as usual with no squealing noises. I waited about ten seconds and then told her to turn ON the A/C. Sure enough, the squealing noises started when the compressor was turned on. I waited about five seconds and then told her to turn OFF the A/C. As soon as she did, the squealing noises stopped. So I sent her on her way with instructions to leave the A/C off as much as possible today.

Unfortunately, this morning's test seems to confirm that the problem is in the compressor - agreed? Most compressors nowadays are sealed and do not allow you the opportunity to lubricate their bearings through an oil port of some type. Does anyone know for sure if that is the case with our compressor?

I suppose I'll start pricing a rebuilt unit. But this thing is going to be a bear to get to in the engine compartment with its location under the alternator. Has anyone tackled this job yourself? I'm wary of disassembling any A/C components and will probably decide to find a shop I can trust to do this work, but I might source and purchase my own compressor first.

Well, my research continues today and I would appreciate any additional tips or advice you folks can offer. Thanks for all the assistance thus far.

[cnynctry]

It may also just be the A/C clutch bearings. This happened to me on a different truck (dodge dakota). I thought it would need a new compressor. The first place I took it wanted to charge for the whole thing. Went to a different shop and the guy told me since it was only the clutch on the unit he could replace it.

Now I have no idea if the RX 300 A/C clutch is the same but it would be cheaper if it can be replaced.

[lenore]

This morning I was outside waiting with the hood open when my wife came out to leave.  Last night I ensured that the A/C was switched off so the compressor would not be running when she turned the key this morning. 

She cranked the key and the engine started smoothly as usual with no squealing noises.  I waited about ten seconds and then told her to turn ON the A/C.  Sure enough, the squealing noises started when the compressor was turned on.  I waited about five seconds and then told her to turn OFF the A/C.  As soon as she did, the squealing noises stopped.  So I sent her on her way with instructions to leave the A/C off as much as possible today.

Unfortunately, this morning's test seems to confirm that the problem is in the compressor  -  agreed?  Most compressors nowadays are sealed and do not allow you the opportunity to lubricate their bearings through an oil port of some type.  Does anyone know for sure if that is the case with our compressor?

I suppose I'll start pricing a rebuilt unit.  But this thing is going to be a bear to get to in the engine compartment with its location under the alternator.  Has anyone tackled this job yourself?  I'm wary of disassembling any A/C components and will probably decide to find a shop I can trust to do this work, but I might source and purchase my own compressor first.

Well, my research continues today and I would appreciate any additional tips or advice you folks can offer.  Thanks for all the assistance thus far.

←

I agree the clutch probably is bad. By the way access through the right wheel well by removing the cosmetic dirt panel and right wheel. Access is great then.

[RX in NC]

That's a great point and certainly worth checking into, cnynctry. Thanks for providing your experiences. I'll keep this thread updated as I continue to research our problem. Since the Labor Day holiday weekend is upon us, I'm not going to take any actual repair steps until next week. And that also gives me more time to figure out exactly what the problem is and come up with the appropriate resolution.

Thanks to all of you who've contributed to this thread thus far. If you have additional ideas or suggestions, please keep them coming.

[RX in NC]

I just checked with Lexus parts and they confirmed that the compressor and its clutch assembly are priced and sold separately. But just the clutch assembly itself is $381 from Lexus, and it's $367 from Toyota. I'll check some of the on-line parts houses and perhaps come up with better pricing from them.

I'll take Lenore's advice by removing the right front wheel and plastic dirt panel over the holiday weekend so I can get a peek at how good the access might be before I decide whether to do this myself if it indeed turns out to be the clutch assembly on the compressor.

Thanks again everyone. Keep those ideas coming....

[RX in NC]

Still haven't been able to isolate the source of the squealing. This issue is extremely sporadic and that's been the primary problem. You can't fix what you can't diagnose. I'm convinced that the vehicle sees me coming and decides not to squeal when I'm present.

I'm going to start from scratch by tightening the AC/Alternator belt and then applying a few sprays of belt dressing. I changed that belt in late May using the current Toyota replacement belt; perhaps I didn't tighten it up as snugly as I should have although I certainly thought that I had it about right. But just maybe this is belt noise after all, even though it sounds quite metallic to me on the couple of occasions I've heard it.

Maybe I'll finally catch a break and a little belt tightening and dressing will resolve this pesky problem. We'll see.

[RX in NC]

Since I tightened and dressed the AC/Alternator belt this past Monday, my wife reports that she's heard no more metallic squealing. A/C off, A/C on, cold start, warm start - none of that has mattered and the vehicle is quiet again.

I usually like to leave a little less than a half-inch of play whenever I install new belts. I've followed this formula for thirty years on American, Japanese, Italian, and German vehicles and I've never had a replaced belt squeal on me before. But on Monday I decided to tighten the belt to slightly less than a quarter-inch of play. Maybe this was the ticket and I suppose time will tell. Perhaps the new belt stretched slightly in the 3+ months that it's been installed on the vehicle.

If the squealing returns, I'll report it here. Let's hope it's fixed.

[lenore]

Since I tightened and dressed the AC/Alternator belt this past Monday, my wife reports that she's heard no more metallic squealing.  A/C off, A/C on, cold start, warm start  -  none of that has mattered and the vehicle is quiet again. 

I usually like to leave a little less than a half-inch of play whenever I install new belts.  I've followed this formula for thirty years on American, Japanese, Italian, and German vehicles and I've never had a replaced belt squeal on me before.  But on Monday I decided to tighten the belt to slightly less than a quarter-inch of play.  Maybe this was the ticket and I suppose time will tell.  Perhaps the new belt stretched slightly in the 3+ months that it's been installed on the vehicle.

If the squealing returns, I'll report it here.  Let's hope it's fixed.

←

Hey RX when you replaced the belt was it a Toyota/Lexus belt. I am curious because I had a squeel on my mothers Mustang and until I went to the Ford belt, the noise kept coming back. I usually use after market parts and have no problem but the belt was one of those that seemed to work better with the OEM.

[RX in NC]

Lenore,

I used the current Toyota AC/Alternator replacement belt. It's the same one that either a Lexus or Toyota tech would have used if I had taken the vehicle to the shop. It appears that the key was to tighten it up a bit. We'll see.

[newells4]

Lenore,

I have had the same issue. Wife backs out of garage and RX starts squealing. I had the belts replaced at our local garage. The squeal got progressively worse. A/C engaged the belts would squeal during startup or later when driving. Decided to take it to local Toyota dealer (Lexus dealer too far away). They replaced the new non-oem belts with Toyota/Lexus belts and tightened the new belts. The squeal went away when starting up or engaging the A/C. Now it squeals (not as loud as before) when she drives, but quiets when she is at a stop. I still think it has something to do with the A/C clutch bearings. 83k on vehicle and original timing belt. Hoping it is not timing belt.

[lenore]

Keep us posted, My rx has 119k and new timing belt at 100k still have the original belts to AC and Power steering.

[RX in NC]

newells4,

I doubt that your current squealing is coming from your timing belt. They typically don't squeal because of the precise way they're molded and seated.

I recommend that you pick up a can of belt dressing spray from your local Pep Boys or NAPA and use it to dress both the AC/Alternator belt and the Power Steering pump belt. If your vehicle returns to silent operation immediately after doing so, you'll know that you still have an exterior belt issue.

It may turn out that your AC/Alternator belt simply needs to be tightened a bit more, as ours required. It's been several weeks now since I tightened ours and my wife continues to report no belt noise at all. These RX belts really need to be tightened up more than I'm accustomed to on our other vehicles. So dress your belts and if your noise disappears, tighten your AC/Alternator belt a little more.

Keep us posted.

[lenore]

newells4,

I doubt that your current squealing is coming from your timing belt.  They typically don't squeal because of the precise way they're molded and seated. 

I recommend that you pick up a can of belt dressing spray from your local Pep Boys or NAPA and use it to dress both the AC/Alternator belt and the Power Steering pump belt.  If your vehicle returns to silent operation immediately after doing so, you'll know that you still have an exterior belt issue.

It may turn out that your AC/Alternator belt simply needs to be tightened a bit more, as ours required.  It's been several weeks now since I tightened ours and my wife continues to report no belt noise at all.  These RX belts really need to be tightened up more than I'm accustomed to on our other vehicles.  So dress your belts and if your noise disappears, tighten your AC/Alternator belt a little more.

Keep us posted.

←

I hope you are right about tightening the belts a little more. My experience fromworking on mechanical things, is that sometimes the bearings are going and when you apply extra force on the the belts it pulls against the bearing and seems to quiet down because the bearing can not move in the direction of least force.

[newells4]

I paid the Toyota Dealer $156 on Sep 9th to remove the brand new non-OEM belts and replaced them with new Toyota/Lexus belts. They tightened the belts according to Toyota/Lexus specs. Yes, they are much tighter. The startup squeal has gone away. The new squeal only happens after the vehicle comes up to temperature while driving. It is much fainter and happens with the A/C disengaged. Engaging and then disengaging the A/C stops the noise. It also disappears when the vehicle comes to a stop. Have no idea yet, RX300 is going into Lexus for this one.

Keep you posted.

[bowtie3]

I paid the Toyota Dealer $156 on Sep 9th to remove the brand new non-OEM belts and replaced them with new Toyota/Lexus belts. They tightened the belts according to Toyota/Lexus specs. Yes, they are much tighter. The startup squeal has gone away. The new squeal only happens after the vehicle comes up to temperature while driving. It is much fainter and happens with the A/C disengaged. Engaging and then disengaging the A/C stops the noise. It also disappears when the vehicle comes to a stop. Have no idea yet, RX300 is going into Lexus for this one.

Keep you posted.

←

My wife's 2000 RX300 FWD [ 54,000 miles ] also has a periodic noise coming from the either the A/C compressor or the alternator. When I had it in for a oil/filter change recently I asked them to tell me what the noise is. The tech told me he couldn't hear anything. The service rep said it would be covered under the Certified Warranty if either the A/C compressor or the alternator failed to operate or " fell apart ", but " noises aren't covered under the warranty ". I think this goes into the " fix after the warranty expires " file! I just replaced the top engine mount [ dogbone ] myself; 20 minute job and $51.00 part from Park Place Lexus in Plano, Texas. The dealer wanted about $220.00; $135.00 [ 1 1/2 hr. labor ] and $80.00 parts. Service rep said it's not covered under the Certified Warranty; it's a " wear item "! I'm wondering if the A/C compressor and alternator are going to be " wear items "!

[lenore]

I paid the Toyota Dealer $156 on Sep 9th to remove the brand new non-OEM belts and replaced them with new Toyota/Lexus belts. They tightened the belts according to Toyota/Lexus specs. Yes, they are much tighter. The startup squeal has gone away. The new squeal only happens after the vehicle comes up to temperature while driving. It is much fainter and happens with the A/C disengaged. Engaging and then disengaging the A/C stops the noise. It also disappears when the vehicle comes to a stop. Have no idea yet, RX300 is going into Lexus for this one.

Keep you posted.

←

My wife's 2000 RX300 FWD [ 54,000 miles ] also has a periodic noise coming from the either the A/C compressor or the alternator. When I had it in for a oil/filter change recently I asked them to tell me what the noise is. The tech told me he couldn't hear anything. The service rep said it would be covered under the Certified Warranty if either the A/C compressor or the alternator failed to operate or " fell apart ", but " noises aren't covered under the warranty ". I think this goes into the " fix after the warranty expires " file! I just replaced the top engine mount [ dogbone ] myself; 20 minute job and $51.00 part from Park Place Lexus in Plano, Texas. The dealer wanted about $220.00; $135.00 [ 1 1/2 hr. labor ] and $80.00 parts. Service rep said it's not covered under the Certified Warranty; it's a " wear item "! I'm wondering if the A/C compressor and alternator are going to be " wear items "!

←

Welcome to the wonderful world of Lexus, take your money no problem, cover the warranty issues, problem. All kidding aside Lexus is probably not the only one who does this, extended warrantys and certified warranty by others are just as bad.

[jimmouse]

newells4,

I doubt that your current squealing is coming from your timing belt.  They typically don't squeal because of the precise way they're molded and seated. 

I recommend that you pick up a can of belt dressing spray from your local Pep Boys or NAPA and use it to dress both the AC/Alternator belt and the Power Steering pump belt.  If your vehicle returns to silent operation immediately after doing so, you'll know that you still have an exterior belt issue.

It may turn out that your AC/Alternator belt simply needs to be tightened a bit more, as ours required.  It's been several weeks now since I tightened ours and my wife continues to report no belt noise at all.  These RX belts really need to be tightened up more than I'm accustomed to on our other vehicles.  So dress your belts and if your noise disappears, tighten your AC/Alternator belt a little more.

Keep us posted.

←

Hello, RX,

My 2001 RX AWD has same noise when the AC is engaged. Is it a simple thing to adjust the belt since I do not have a manual to follow? If you can post some pictures about tightening the belt, that will be great.

Thanks for the info.