Can an alternator slow down RX300? Is that whats wrong?

[jjc1971]

Hi all,

New to Lexus and new to here. I did try to search but couldn't find a thread related to this. Also posted this on the wrong thread - sorry. 

Bought a 2004 RX300 a couple of weeks ago and I've been really pleased so far. But I now have an issue. A couple of days ago the belts squeaked for about a minute but it wasn't first start up of the day so I noticed and thought that's odd.

Since then belts have squeaked a few times and again for a minute only and not from cold.

Yesterday got in it to leave work at 5pm and got the squeak but also the red battery light was on for the first time so I turned off all the power hungry items. After about 5 mins the battery light went out again, and then I pulled over to pick up groceries. When i restarted car started ok with no noise and no red light but no power. There was nothing to indicate it was in limp mode, no warning lights just wouldn't pull.

Any thoughts? My initial uneducated thought is alternator. Alternator may have semi 'seized' so with the squeak yesterday was alternator refusing to turn, but then it did turn but is so stiff its basically nearly stopping the engine but it is reluctantly turning hence the battery light is out.

Is there any way I can test the alternator? Is my theory idiotic?

Any help greatly appreciated.

[eugene.s]

Hi James, 

I am not a car mechanic or electrician either but from all my experience as a car user:

(1) If my belts squeaked, I wouldn't think of a problem with the alternator, I would think that the belts become loose and that I need to adjust the belt rotors to provide a proper belt tension.

(2) I believe the normal battery life is 3 years (I've rarely seen a battery to go beyond that). If I were you, I would recharge or replace the battery and see if the battery indicator ever comes on again.

(3) If you believe that your problem is deeper than that, I would suggest that you first check your car for any error codes ("computer diagnostics").

(4) You may also try a "consumers" check -- to check what exactly drains your battery when the car is off. This implies a car electrician to connect special devices to your car's wires while it's on/off. No need to remove anything other than the plastic covers under your hood.

(5) If you may want to check your alternator individually, it will need to be removed from the car to be tested on a stand. If you ever go this route, I suggest you make sure that people doing the alternator removal/installation have done it before on your particular car model (if the procedure on an average car takes 1 or max 2 hours, on a Lexus car it may take up to 6 hours -- so, you'd want to ensure that the mechanics to be employed have done this on your particular car model before and won't be experimenting). 

I believe for each of (1) to (5) you don't necessarily have to go to a dealer, you can call on any tested car mechanics/electricians in your place. If you describe in this thread where exactly you are located, I hope that local forumers would be able to help you.

Good luck,

Eugene

 

 

[Filehorse]

I think you have two possibilities: (1) the accessory drive belt is loose and needs to be adjusted.  (2) you have an alternator bearing seizing up and the belt is slipping over the pulley.  If the belt is loose, adjust and problem solved.  If the belt is tight, loosen it and see if the alternator pulley will spin freely with no drag.  If it doesn't, problem solved with a nre alternator - and they ain't exactly cheap but it is an easy DIY.  Good luck.

[jjc1971]

Hi Eugene,

That's great advice. Thanks. Firstly I'm in UK not US so not sure if there are any cotswolds forumers? 

I've just checked it out and the belt going round the alternator is good and tight but not overly. Its about the same as alternator belt tension on my other car. 

I started the car up and it was fine, no squealing, no battery light.

So this shows that the Lexus alternator does at least turn and hasn't fully seized. And the belt is in good condition and the right tension.

Which means I don't understand:

1) why it squeals occasionally

2) why it didn't charge the battery for 5 minutes

But actually my biggest concern - 3) why the car was so underpowered it couldn't get up a hill last night.  

Does the lexus give any warning signs if it goes into limp mode? Could it have gone into limp because of the alternator hiccup?

Thanks

James 

[jjc1971]

Actually not even sure if the RX300 has a limp mode. 

Filehorse,

Thanks. Did check out the belt and it seemed ok as above. But annoyingly so did the alternator. When it was started from cold. I guess possibly a bearing could get sticky when its warmed up but ok when it is cold? It felt as though the engine was being held back. Fuel consumption was showing noticeably lower than normal even when going steadily at 50. It felt like the engine was using a lot of fuel to not go very fast. Like towing a truck.

Thats good to hear about the alternator change. It's nicely located at the top of the engine for a change.... I can live with an alternator change. 

[Filehorse]

While you're under the hood, loosen the belt and check any other accessories (A/C, power steering pump) to see if there is any significant drag.  I have trouble thinking it's just a coincidence that you have a squeaking belt and a Alternator/Battery warning light.  In a vehicle of this age, you really need to find a good independent shop that specializes in Toyota/Lexus repairs.  Under the hood is all Toyota so there should be one in your area you could trust to do good work at a fair price.  The parts will be about the same price as the dealer but the labor rates should be significantly less.

Good luck and let us know what you find that solves the problem.

[jjc1971]

Filehorse, 

Thats a good point. Any tips on how to loosen the belt? On other cars I've worked on there's tension put in by a slide arm where the alternator connects. Is this how you would do it? I can't see out here now - its gone dark as its early evening here and cant find the torch!

I'll look out an independent. Its so hard to find one to trust though. Although I don't trust main dealers either. On my Volvo XC90 just before Xmas went in for a dpf filter and the dealer diagnosed it as a replacement gearbox for £5,800. I told them not to be silly, spoke to their engineer and when I said I thought they had got it wrong he completely agreed. 

I'll try easing the belts because if there is AC and other parts on the same loop then that might be a cause as you say. I could have imagined it but I did feel the steering was a bit odd.

Thanks

 

[eugene.s]

Hi James, having read through your and others responses, I think you must do (2) from my original post. Then wait and see. And revert here if any further trouble. Maybe you may prefer to do (1) from the same but that doesn't appear critical to me now at all.

P.S.: When in your further posts you may prefer to refer to "not [being] cold", please always advise your place or its temperature. I've lived in London before; your feeling for "cold" may be very different from what the "cold" means around the world.

[Filehorse]

Just looking at the belt arrangement on my 2000 RX300 and the adjustment has to be either via the alternator or the A/C compressor.  Either way, it's not obvious like the old days but it has to be there somewhere.  If you push down on the belt midway between the alternator pulley and the crankshaft pulley there should be about 1/2" of depression available and that's with a pretty stout finger pressure.  I had my alternator replaced sometime last summer and this is where the indy shop left the belt tension.  If there's much more than that much depression available you may have found your problem.   It'll be interesting to see what you discover on your quest.

Again, good luck.

[jjc1971]

Eugene,

Good point on temperature. By 'not cold' I mean the engine is at normal operating temperature having been running for 10 mins. Ambient temperature is cold cold. Your memories of London are on the money. Right now its -1 degree celsius. Cold.

I fully accept that the battery may have seen better days, but to my mind that couldn't cause the belt to squeak?  When i say the power has gone I don't mean electrical power - I mean engine power. It runs fine and turns over and lights work and seat warmers do too (very necessary here right now) but when I move off there just isn't enough power from the engine to get the car up a hill. Like its in limp mode.

So something is interfering with engine power. Significantly. And I don't think battery can do that. Because of the squeaking and cutout I was exploring something on that drive belt seized slowing the engine speed down and as the battery charge light was on alternator seemed like a good place to start. But the alternator actually moves ok, so I need to explore the other components on the same drive belt.

But I certainly will change the battery soon. I need to isolate that its not a fully seized engine first as I have no desire to waste money on ancillaries if the whole engine block is seized!

 

 

[eugene.s]

Why are you so focused on the belts?

If you are so energized, go to https://secure.drivers.lexus.com/lexusdrivers/home

Or a relative page to the UK.

[jjc1971]

Filehorse,

Thanks for taking a look - really appreciated :)

I have the same - half inch play in the centre of the pulleys. I used to have a 1973 Jensen interceptor and the AC unit seized on that while I was driving. Jammed everything solid and set fire to the drive belt. So I think I probably for no valid reason lean towards that at the moment. But it could equally be nothing to do with that drive belt.

I hate cars. I have lots and love them really, but actually I bought this because Lexus 'just work' apparently. The reviews are so good. And I urgently needed a daily that I could just drive. XC90 is still at the garage 3 weeks later, and the toys are in the garage off the road. So frustrating to be on forums so quickly with a Lexus. I know its an old one but its done 90k and I'd hoped for more if I'm honest. 

I'll let you know how I get on with steering and AC on the drive belt. And thanks!

[jjc1971]

Eugene,

Ok. So somehow I have clearly offended you. I really am not sure how. And I'm not sure directing me to that page added anything.

I'm not focussed on belts. I'm trying to get to the bottom of an issue that is causing the engine to not be able to deliver full power. And the belts are connected to items that can seize as well as the engine. And I have a squeaking belt. And a battery not charging light which happens if the thing attached to the belts fails or the belt fails.

It may be nothing to do with the belts but there sure is enough 'coincidental' stuff to be worthwhile exploring it. I did think the point of forums was to explore stuff and gather opinions. I wouldn't come here if I had the answers? But I do confess I can't see how changing the battery would stop the squeaking belt, or get the car out of limp mode. Sorry :( 

[lenore]

I would spend the afternoon and remove both belts, than turn by hand the power steering pump, alternator, and AC pump.  The alternator should turn very easily, the Power steering pump may have a little resistance, and the AC pump with no power should spin easily.  I have seen the clutches go bad on AC pump and cause belts to actually break. 

[jjc1971]

lenore,

Thanks that sounds very sensible. I'll try that. Any tip on easiest way to get the belts loose? Is there a tensioner somewhere that will ease it enough to get the belts off?

Thanks

[lenore]

I would spend the afternoon and remove both belts, than turn by hand the power steering pump, alternator, and AC pump.  The alternator should turn very easily, the Power steering pump may have a little resistance, and the AC pump with no power should spin easily.  I have seen the clutches go bad on AC pump and cause belts to actually break. 

The alternator bolt is the adjustment, there is a pivot bolt that needs to be loosened and then the adjuster bolt....

[lenore]

Here is tube procedure: