artbuc

I bought the Gates TCK257 kit from RockAuto for $86.89 which includes the T257 timing belt plus two idler pulleys. RockAuto sells the T257 belt separately for $18.29 meaning I paid $68.60 for the two idler pulleys. The "Gates" idler pulleys were made in Korea using GMB bearings. RockAuto sells the Dayco kit 84063 which inlcudes both idler pulleys w/o belt for only $44.89. The "Dayco" pulleys are identical to those in the Gates kit (GMB bearings). Better yet, I just discovered RockAuto sells Koyo idler pulleys which are identical to those installed at the factory. Unlike Gates and Dayco, the Koyo pulleys can be purchased separately for $15.72 and $23.79 or $39.51 total. So why pay $68.60 (Gates) or $44.89 (Dayco) for GMB idler pulleys when you can get factory original Koyo's for only $39.51?

Heidi, I just changed the timing belt & timing belt idler pulleys on my wife's 99 RX 300 which has 81, 866 miles on it. Your experience with the Lexus dealership matches those I have had with two separate dealerships. They are an interesting mix of incompetence and dishonesty. But, they do give you free coffee and cookies! If they did, in fact, replace your timing belt, both pulleys were exposed and could have easily been inspected. However, you can not accurately predict the life of idler pulley bearings with a visual inspection. These pulleys have sealed bearings. Signs of looming failure are: (1) radial streaks of grease, (2) excessive play, (3) noise or (4) rough spots. If you had none of these signs, it is unlikely that your idler pulleys failed on their own 9 months after Lexus worked on it. Even if these pulleys were inspected and looked good, Lexus should have discussed the desirability of changing them because they could likely fail before you need another timing belt. They should have also discussed this very point with you about the water pump, crankcase front seal and camshaft seals. Getting to the pulleys to replace them will require the exact same labor that it takes to replace a timing belt. I changed the idler pulleys on my wife's car because I had already bought them. However, I could hardly tell the difference in play between the new and old pulleys. You are right, I don't see how they knew your idler pulleys were bad unless they "thought" they could hear them. They could have removed the top timing cover relatively easily and checked the top idler pulley with a stethoscope but I doubt it. However, to check the tensioner (lower) idler pulley would have required major disassembly. Sounds like a total scam to me. To properly replace a timing belt, you should remove the hydraulic tensioner to inspect it. My guess is that they tried to save time by clamping the tensioner idler pulley against the hydraulic tensioner and somehow damaged the tensioner idler pulley. However, like we said above, I don't know how they could determine the tensioner pulley was bad wihout major disassembly. Bottom line is this: if you can't do the work yourself, be prepared to get cheated by Lexus.

Thought some of you may be interested in this. My RX has a Unitta timing belt. So, all 3 drive belts from different suppliers: PS from Dayco, Alt/AC from Mitsuboshi and timing from Unitta. Never heard of Unitta so I did a little checking. Unitta is a joint venture formed between Uniroyal and Nitta (Japan) in 1971. As far as I can tell, Nitta did not manufacture automotive belts. In 1986, Gates bought Uniroyal Power Transmission presumably to get their timing belt technology and manufacturing capability. In 2002, Unitta was renamed Gates Unitta to reflect the Gates purchase of Uniroyal Power Transmission. Gates Unitta supplies the Asia Pacific region. Gates and Gates Unitta timing belts come in different packaging but have the same product name and description. My guess is that they are the same belt probably made in the same plant. Also, Gates timing belts are made from Highly Saturated Nitrile rubber whereas Dayco are made from EPDM. HSN has superior mechanical and chemical resistance properties. I bought Gates belts from RockAuto before I started work. Upon inspection, I discovered the tensioner idler pulley is bad, so I ordered Gates timing belt kit. Rockauto had already sent my belts so now I have an extra Gates timing belt. If anyone wants it I will sell it to you at my cost.

My 99 RX300 came from the factory with a Dayco Power Steering Belt and a Mitsubishi Alternator Belt. Don't know about timing belt yet because I haven't pulled the cover. Dayco tells me their premium aftermarket belts have the same polyester cording and EPDM rubber. The only difference is that they make the aftermarket design more universal to fit more applications. This is what keeps their cost down. Dayco Timing Belt from RockAuto is $18. I can get a Lexus Timing belt for about $45. Not much difference in the overall scheme of things, but I don't want to spend $27 more for basically the same belt. Has anyone out there used a Dayco or other aftermarket timing belt? Have you been satisfied with it?

Thanks tjmc11. We may be talking about two different things. The "tensioner" I have seen included in kits, eg Dayco and Gates, is actually the No. 1 Idler Pulley, although Gates and Dayco call it the tensioner. The "timing belt tensioner" in the shop manual looks like a hydraulic cylinder with a "push rod". You remove this tensioner by carefully alternately loosening its two mounting bolts. When completely removed, the push rod extends 10mm. According to shop manual, you have to compress this push rod with a press using between 200 & 2205 lbs of force in order to reinstall it. You temporarily hold the push rod in place with an allen wrench to reinstall it. I assume the actual force required is based on the condition of the tensioner. The tensioner push rod "loads" the No. 1 Idler Pulley so that it rotates on its pivot mounting bolt thereby tensioning the belt. Did your kit include the push rod tensioner or just the No. 1 Idler Pulley? Which kit did you use? Is it possible to change the timing belt without removing the hydraulic push rod tensioner? Thanks again.

My wife's 99 RX is exactly 9 years old with 83k miles. Brother-in-law is a master mechanic who owns his own business. I don't take my cars to him because he is too expensive but he does know his stuff. Talked with him last night at the family Christmas Eve party. He said that timing belt should be replaced at 90k miles or 6 years, whatever comes first. He has seen timing belts last 9 or more years but has also seen many fail at 7-8 years. Good news is that our engines are non-interference. Bad news is that my wife could get stranded and need car towed. Think I'll get motivated and change all belts and water pump as preventative maintenance. One quick question: Anybody have any tips on how to reload tensioner piston? Shop manual says to use a press which I don't have. Maybe I'll try a big C--clamp or use some long bolts with a piece of bar stock?

Do yourself a big favor and buy Toyota/Lexus OEM pads. No dust, excellent stopping power and last 70+k miles.

RE 99 RX w/AWD @78k miles I have read almost all threads in this forum re P0171. They mostly end in debates with no one ever telling what they did to resolve this code. Here are some of the sticking points: 1. One says 99% of time it is MAF and other says it is almost never MAF. 2. One says to clean MAF and many claim great results by doing so and others say it is useless to clean, you must buy new. 3. One says P0171 refers to bank 1 too lean so it can't be MAF while another says (correctly I think) P0171 refers to both banks. 4. One says it must be A/F sensor while others say that is almost never the problem. 5. One says Toyota had a problem with ECU being incompatible with A/F sensor output and Toyota replaced under warranty. I would like to hear from anyone who has had a P0171 code, without any other codes, who did something to permanently fix the problem. Thank-you.

OK, I answered my own question. RockAuto offers Standard Motor Products for $163.79 and Airtex for $248.79 both plus S&H. Lexus of Wilmington had one in stock for $223. Picked-it up on Saturday and guess what? It was DOA!!! Resistance across both open and close circuits should be the same and about 23 ohms at room temp. This brand new Aisan IACV had 28k ohms across "close valve" circuit and over 38m ohms (basically open) across "open valve" circuit. When I put 12 volts across "open valve" circuit it did absolutely nothing. I can't get another IACV until Tuesday. Very disappointing. UPDATE. Turns out nothing was wrong with the new Lexus IACV. My Lexus Repair Manual is wrong! Volume 2, Pages SF42 & SF46, describe electrical checks for IACV. All of this info is incorrect. It applies to the rotary solenoid type IACV's used in some other Toyotas such as my 99 Avalon. The IACV in my RX is magnetic induction which operates off a pulse signal. Resistance measurements scross the coil circuits are meaningless and you cnnot operate it manually by applying 12VDC. Good news is I have a new $227 IACV, bad news is my old one worked fine - just needed to be cleaned.

Hmm lets see you removed the throttle body, removed the ACIS actuator bracket and removed the PCV hose. THEN accessing the spark plugs wasnt very hard!! Point taken. I should have said, if you already have the throttle body removed for other reasons you can easily get two. And, it only takes a few minutes to remove ACIS bracket/PCV valve&hose to get to third.

OK, I answered my own question. RockAuto offers Standard Motor Products for $163.79 and Airtex for $248.79 both plus S&H. Lexus of Wilmington had one in stock for $223. Picked-it up on Saturday and guess what? It was DOA!!! Resistance across both open and close circuits should be the same and about 23 ohms at room temp. This brand new Aisan IACV had 28k ohms across "close valve" circuit and over 38m ohms (basically open) across "open valve" circuit. When I put 12 volts across "open valve" circuit it did absolutely nothing. I can't get another IACV until Tuesday. Very disappointing.

99 RX300 w/78K miles Already had throttle body removed to service IACV (please read my other thread) so I thought I would check-out the infamous 3 plugs next to firewall. Middle and driver's side completely accessible with throttle body removed. On passenger side, I removed two screws holding ACIS actuator bracket so I could swing it out of the way. Then removed PCV valve/hose. This provided easy access. As expected, spark plugs looked great. Sharp edges and perfect gap. Threads were getting a little corroded so I dressed them up with anti-sieze and re-installed. Figure I will replace at 120k. By then I will likely need to service IACV again so little to no wasted effort. Many posts re the difficulty of removing these plugs, but believe me it just isn't that hard.

At only 78k my IACV is shot . Should I replace with Toyota OEM or can I go aftermarket? I would appreciate any suggestions on what and where to buy to get best price and quality. Thanks.

Bluestu, my shop manual doesn't specify Bank 1 - just says Fuel System Lean. MAF checks out perfectly, electrically speaking. I did clean it although it wasn't very dirty. Put it back together and started car. Idle soeed was low. Askled wife about it and she said this problem started about 3-4 days ago. Tore her down tonight and removed IACV. It wasn't gunked up too badly but IACV open circuit had no continuity. I am very disappointed that IACV failed at 78k miles. Just a few months ago I had to replace an A/F sensor - pretty pricey too because I have a CA spec car. Can't believe this "Pursuit of Excellence" Lexus is already starting to nickle and dime me at less than 80K. Oh well, at least the trans hasn't failed, yet. BTW, should I consider an aftermarket IACV or stick with Toyota OEM?

RE: 99 RX300, I did the search and still have the following question: Shop manual says P0171 could indicate problem with MAF, ECT sensor or Bank 1,2 Sensor 1 (A/F Sensors) among other things. I get only P0171 and no other codes relating to MAF, ECT or A/F sensors. Does that mean I can rule out these items?

You math is correct; however, IMHO, the percentage of trans related posts on this forum has absolutely nothing to do with the relative quality/reliability of the RX AWD tranny. If 50% or 95% of the posts were trans related it would still mean nothing. What is needed, but apparently not known, is the actual failure rate for cars which have been properly maintained. I imagine Toyota has a good handle on this but their number is probably low since not all failures are reported to them. What Toyota does know but hasn't yet admitted is whether their engineers deemed it necessary to make fundamental design changes to correct unacceptably low reliability. Having said all that, several posters, including me, have reported that Lexus techs and/or service managers have admitted, off-the-record, that RX trans have fundamental design issues. Add that to my personal experience that trans fluid becomes muddy brown after 15k miles of easy driving and the number of dealers offering/recommending frequent trans fluid flushes, I think you can safely assume something is very wrong.

I am a long time Toyota owner and former strong advocate. Over the last 15 years, I have bought brand new LS400, RX300, 4Runner and Avalon XLS (also bought a new Corolla in 1975 and new Tercel & Cressida when I returned from overseas in 1984). Neighbors on my street have bought 4 new RX300's, one ES300 and one Sequoia. Collectively we have dealt with 3 Lexus and two Toyota dealerships. I can tell you that Toyota no longer means quality and reliability. All of these cars (not Corolla, Tercel or Cressida) have had major problems. Toyota/Lexus have been unwilling to help and dealership work has been shoddy to put it mildly. Most recent problem was neighbor's Sequoia with 79k miles which needs a new engine. I will never, NEVER, buy another Toyota product. Perhaps you will be ok because you have made 177k without encountering problems. Good luck. Toyota stinks!

After confirming I needed a new A/F Bank 1 Sensor 1, I bought a Denso aftermarket from RockAuto. When it came I checked heater resistance to make sure I had the right one. Got 15 ohms instead of 1 indicating I had Sensor 2. Rockauto talked with Denso and said all was well. I called Denso myself and found out my RX300 was a Calif Emssion car even though I bought it brand-new in Delaware. I checked the emissions sticker under the hood and sure enough I have a Calif car. This means I need the $165 sensor instead of the $83 one. I don't remember the salesman telling me the car was built to CA standards. So, if you need a new Bank 1,2 Sensor 1. Make sure you know if you have a Calif vehicle. PS Bank 1 Sensor 1 is a snap to remove even if it is tucked between the engine and firewall.

Hope you get an answer because I have this problem (high initial rpm) all of the time. So far no one has been able to help me. I have concluded my problem lies with the ECU. However, based on your experience, perhaps my IACV is the problem. I had ruled that put because idle does ramp down to normal as engine warms up and idle control is fine at normal engine operating temp.

Think I answered my own question. I believe there are misprints in the "Trouble Area" columns on page DI-16, Volume I for Codes 1130, 1133, and 1135. When you look at the details for each code on pages DI-102 and 108, they say Sensor 1, NOT Sensor 2. I also found another misprint on page DI-13 for Code 0125. It says heated ox sensor and heated ox sensor circuit are possible trouble areas yet on page DI-46, it says A/F Sensors Bank 1, 2 Sensor 1 are possible trouble areas. The Heated Ox Sensor is Bank 1 Sensor 2. When you combine confusing terminology with shop manual typos, you have a real mess. I'm betting the tech was right and I have a bad Bank 1 Sensor 1 is bad.

Re 99RX Check Engine Light came on. Had four Codes - P0125, P1130, P1133, P1135. Shop Manual says: P0125 Trouble Area is Bank 1 & 2 Sensor 1(A/F Sensors) or ECM. P1130, P1133, P1135 all list Bank 1 Sensor 2 as Trouble areas BUT, the Detection Item is Bank 1 Sensor 1. The Tech said he wasn't getting any output from Bank 1 Sensor 1. So, which Sensor is bad? Also, what is the difference between a "Detection Item" and a "Trouble Area"? For Codes 1130, 1133 and 1135, why does the manual list Bank 1 Sensor 1 as the "Detection Item" but then say Bank 1 Sensor 2 is the "Trouble Area"?

Mkae sure you remove, clean and lube the caliper slide pins. My rear ones were frozen when I replaced original brakes at 73k. Also I like to steel wool the polished steel shims which allow the pad "ears" to slide freely. Don't forget to lube the anti-squeal shims. All these things make the new brakes work smoothly and quietly.

MrEhden, can you give some more details? Make/model # of cooler, where purchased and installation tips?

Thanks Lenore. Yes, my wife does almost all stop and go, around town driving. This is the first time I recall anyone suggesting to deactivate the O/D. How did you decide to take that step? Does it seem to be helping you? Sounds like you are doing a drain/refill every 10-12k miles on your new tranny. How does the used ATF look? Any difference in appearance on the third drain/refill vs the first? Thanks and good-luck to you also.

Quick update. 15 months and 13k miles later I have done another drain/refill. ATF looked noticeably different than new stuff, sort of a muddy brown/red color. Unlike the 60K drain, ATF from transfer case and drain pan looked the same. The first ATF drain I did was at 27k miles. At that point I could not tell the difference between new and used ATF. That tells me that something bad is going on in my transmission. If the ATF itself was breaking down after 13k miles, I should have seen that on the first drain at 27k miles. I did the second drain at 50k miles, also not seeing too much difference between new and used. I know there has been much discussion about what causes what. Does "brown" ATF cause the trans failure or does the trans failure (burned clutches, etc) cause the ATF to turn brown? Considering the bad state of my ATF, I will do another drain in a few weeks to get more fresh ATF in the system. I think I'm on a collision course with the infamous trans failure.