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wwest

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Everything posted by wwest

  1. Gee.....
  2. It isn't always a question of getting, being, lost, mostly it's a question of finding the most direct route in the local area. But you made a good decision, the Lexus built-ins are super expensive and mostly worthless in comparison to the Garmin portables. TRANSPORTABLES. I have an '01 RX300 with 5.1 Nav and a year old Garmin and the Lexus will almost NEVER route me the most direct way but the Garmin does.
  3. Yes.
  4. Since late in the last century manufacturers have been doing almost everything possible, conceivable, to improve the safety factor of vehicles with automatic transmissions when operating on low traction surfaces, most especially FWD or front torque biased AWD vehicles wherein engine compression braking will be the most detrimental. It has now become common knowledge throughout the industry that engine braking on the front wheels will oftentimes interfere with the operation of ABS to the detriment, obviously, of the owners/passengers. For those with long term stick shifting experience think about how often you wish for a clutch as you drive along in wintertime with your automatic shift transmission, especially a FWD one. Most new owners manuals state quite explicitly that engine braking cannot be attained absent a manual downshift and in some cases not even then unless you disable, completely turn off, cruise control. This whole widspread episode of throttle delay, 1-2 second downshifting delay/hesitation has arisen as the result of widespread industry adoption of a new automatic transmission shift pattern/sequence adopted late in the last century. The technique involves quickly upshifting these electronically controlled transmissions/transaxles upon any FULL lift-thottle event wherein should the current gear ratio be retained would result in a significant level of engine braking. The idea is to improve the safety factor by virtually eliminating engine braking that cannot be overcome by the operator absent a quick shift into neutral, an action currently recommended by the AAA, but of itself fraught with peril. So, rather than retarding the timing, as was previously done, to reduce the road speed of cruise control, I wouldn't be at all surprised to see the use of rear braking only via the traction control system to initially slow the vehicle. But it is now pretty clear that applying the brakes, in total, to do this will be potentially safer, overall, than the use of engine braking which cannot be alleviated by the anti-locking braking system should it subsequently be needed. Even slight engine braking on an extremely slippery surface, an icy bridge deck comes to mind, can easily result in loss of control even on a RWD vehicle, but the potential for loss of control of a FWD in these insatnces rises dramatically in comparison. Be careful out there....
  5. If you browse about your will find owner complaints of throttle lag or engine delay/hesitation for Ford, VW, Toyota, Lexus and others, all concerning vehicles with automatic transmissions and mostly FWD or front biased AWD vehicles. It is my firm belief that sometime in the mid to late ninties someone, or some group, with TONS of clout over the automtive industry issued an edict that the safety of FWD and front torque biased AWD had to be brought into line with their RWD and rear torque biased AWD brotheren. My vote goes to the automotive insurance industry. Accident statistics most readily available, certainly with the CLOUT and enough synergy with the industry to want to keep this on the QT. The safety issue involved the potential for loss of directional control due to engine braking, especially FRONT engine braking, in wintertime adverse roadbed conditions. There is also the issue of the potential for engine braking to interfere with ABS, again especially detrimental for FWD vehicles. So, late in the last century the shift pattern/schedule was revised across the industry to address the safety issue. The new shift pattern dictated that anytime there was a FULL lift-throttle action by the driver the transaxle would be quickly upshifted so as to prevent any significant level of engine braking. The problem that quickly arose from this change was that if the driver quickly returned to acceleration "mode" the engine was now at idle and the just previously commended upshift would deplete the ATF pressure/flow reserve. With little or no ATF pressure/flow available the subsequent downshift due to the driver's re-application of pressure to the gas pedal could not be quickly completed. As evidence of Lexus has now replaced a LOT of early RX300 transaxles. By 2001 Lexus had figured out the problem and increased the displacement of the ATF oil pump, gear type oil pump, to provide more pressure/flow at engine idle. So, the 2001 RX300's, even with all equipped with the extra ATF cooling via the tow package, OVERHEATS the ATF to the point that the recommended traansaxle ATF service interval has declined from infinity (the life of the vehicle actually) to every 15,000 miles. What to do, what to do...?? Oh, I know, let's use DBW, e-throttle, to delay the onset of engine torque until the subsequent downshift can be completed, the clutches firmly seated. So the RX330 used the old standard ATF gear pump displacement but was equipped with DBW "to protect the drive train". Regretably some one else in engineering had already decided that the VC, Viscous Clutch, in the AWD version was contributing to the overheating of the ATF and so it was removed, not to return until the advent of the RX350. Is Lexus listening, do you suppose? The final FIX... SNOW mode...Assuming the new shift pattern upshift technique is to help alleviate accidents due to loss of directional control arising for engine braking, why not just have a SNOW mode that can be activated by the driver, by a rain sensor, or if the OAT hovers around or below freezing? Upon a full lift-throttle event in SNOW mode the transaxle would remain in the same gear ratio (ready to SURGE forward on command) but the engine RPM, via DBW, would not be allowed to fall enough to provide a significant level of engine braking to the driven wheels, FRONT, rear, or ALL. Absent being in SNOW mode the shift pattern could be the same as it was pre-2000, NO upshifting on full lift-throttle events. No HIGH potential for engine braking, FRONT especially, to put your life at risk or interfere with ABS if the roadbed traction is satisfactory. I guess on second thought ABS interference via engine braking might still be an issue. But that could addressed by keeping the upshift pattern but delaying it until the brakes are applied.
  6. Assuming the new shift pattern upshift technique is to help alleviate accidents due to loss of directional control arising for engine braking, why not just have a SNOW mode that can be activated by the driver, by a rain sensor, or if the OAT hovers around or below freezing. Upon a full lift-throttle event in SNOW mode the transaxle would remain in the same gear ratio (ready to SURGE forward on command) but the engine RPM, via DBW, would not be allowed to fall enough to provide a significant level of engine braking to the driven wheels, front, rear, or ALL. Absent being in SNOW mode the shift pattern could be the same as it was pre-2000, NO upshifting on full lift-throttle events.
  7. My filter screen wasn't dirty enough to require any special cleaning solvent or effort. There are three (4?) small magnets laying, magnetically "attached", on the bottom of the sump pan which in my case had some small amount of metal filings attached, not enough to worry about IMMHO.
  8. Yeah...thanks a bunch, Audi...and morons everywhere. I hate this feature. I've gotten in the habit of always doing it fairly forcefully, but ours still feels sticky after it's in gear. Not for long, as if whatever it is needs to warm up maybe two minutes before it's okay. Next time, I'll stay parked and time how long it takes...after I give the solenoid thingy a good second. I thought it was mechanical, 'cause if you hold the 'button' down under the top-left of the shift lever, it'll shift outta park regardless of whether there is a key in the ignition or the brake on. This is why I've not wedged it down, permanently. That "button" is simply a method for manually actuating the electrical solenoid plunger.
  9. Thanks to Audi's unintended acceleration episode there is now an electrical "lock-out" solenoid that prevents you from shifting from park absent having foot pressure on the brake pedal. The brake pedal switch may be slightly maladjusted so it takes an unusual level of brake pedal pressure, or the solenoid (COLD??) itself may be sticking slightly. Also, if you happen to try to move the shifter slightly before stepping on the brake pedal you may inadvertently put the solenoid plunger in a bind and now you must release the pressure on the shifter for the plunger to move to the unlock position. It is oftentimes good practice to step on the brake pedal firmly and then hesitate momentarily, 1001.., before moving the shifter from park.
  10. At ~40k miles the ATF in my 2001 AWD RX300 smelled burned and looked dirty. I drained the transaxle and installed the 4 qts of ATF Lexus sold me as adequate. Shortly thereafter I again noted that my ATF was looking dirty and smelled slightly burned. It was at this point that someone on one of these forums informed me that the diff'l also runs in ATF and has a separate sump drain. Back to Lexus, purchase 5 qts, against the advice of parts guy who still insist only 4 qts required. This time I not only removed both drain plugs I also dropped the sump pan. The bottom of the sump pan was covered with about 1/8" of debris that looked like ground up pencil lead and was not magnetic. I cleaned out the pan and filter, installed 5 quarts of ATF and now at ~60k miles it still looks pristine. I was suspicious that heat from the VC operation within the PTO was contributing to the ATF burning so I checked the gear oil condition which was okay. I have become convinced that the overheating of the ATF in my '01 (possibly '02 & '03 also) is the result of Lexus upgrading the ATF oil pump to a higher volume capacity to overcome the transaxle failures in the earlier RX models that resulted from the FWD shift pattern/schedule change made late in the last century. In '04 they went to DBW to "protect the drive train" and were able thereby to go back to the low volume ATF oil pump and avoid overtaxing the ATF.
  11. 153,000 miles... Your torque converter is likely a tad loosy-goosy, especially starting out cold. Feels sorta like a slipping clutch until it "winds-up" to maximum slip.
  12. Two components, exactly the same, used for two different purposes. Both are used to detect oxygen content in the exhaust gasses. First one to make sure the A/F mixture is correct, second one to be sure the catalyst is operating correctly.
  13. I can't think of any easy way to prevent the upshifting upon lift throttle but if enough folks are interested we could come up with a "warning", LOUD Beep-Beep-Beep, when the throttle servomotor is not following the accelerator pedal positioning as quickly, as responsively, as "normal".
  14. Yes, the Garman handheld portable GPS/Nav is head and shoulders over, better, than any of the "captive" systems, including, most especially, the 5.1 Rx version.
  15. The RDX only had two shortcoming insofar as my research uncovered. A) Tire chain restriction. B) Different SH-AWD implementation. According to the owners manual tire chains can ONLY be used on the front. Unlike the Toyota/Lexus AWD versions, RX, HL, Sienna, the RDX actually seemed to have enough clearanc ein the rear to accommodate even link tire chains. Several coversations with factory reps on this matter went no where, none of then could explain the reasons for the restriction, and at least one felt it might simply be a typo based on the past experiences (Acura = FWD) of the tech writers. The original version of SH-AWD included the ability to vary the overdrive ratio to the rear drive and then two variable coupling clucthes, on for each side. Now the one for the RDX and MDX has a constant overdrive ratio. A third, minor complaint, for me was the "business" of the dash. Were I to somehow end up owning one the first thing I would do is find a way to "!Removed!" the point at which the turboes begin to spool up and bring on boost. I'm far from a boy-racer mentality these days so I'd much rather have the increased FE.
  16. 1. More and more, at least for me, it begins to appear that the premature transaxle failures only involved, primarily, the '99 model year. Also, I quite firmly believe those failures were the result of the adoption of a new shift sequence/technique and those problems, at least for the Camry, seem to remain with us until this day, the '07 model year even. 2. It is my understanding that Toyota made an immediate design change to the engine structure to alleviate the problem for newly manufactured engine blocks. 3. Main oil seal problem...?? 4. The DBW system is NOT the problem, it is the FIX. Until there is notice of a final definitive fix for the transaxle subsequent/sequential downshift delay the DBW system will continue to be used to "protect the drive train". Ford has just announced that the new FWD Ford Edge's transaxle uses a variable displacement ATF oil pump for improved efficiency. Seeing as how Ford's FWD vehicles seem to be experiencing the very same problems as Toyota/Lexus I suspect the variable volume ATF oil pump will be Ford's final fix for the problem. But also keep in mind that as of '04 the VC, viscous clutch/coupling was dropped and so you will be relying only on the traction control system braking for TRUE AWD activity. It is my understanding that the RX350 again has the VC. If your wife truly needs AWD then have her test drive the new Acura RDX with SH-AWD. Were I shopping today to replace my 2001 AWD RX300 the BMW X3 w/manual would be first on my list and the RDX second, with a new RX350 a distant third.
  17. Yes, a Lexus will be more expensive to maintain, fix, as will any upscale vehicle. More "things", accessories, etc, some of them fairly complex, often many of them of new designs just being introduced to the market and to the world of the dealer service personnel. Sorry, the leading edge is oftentimes the BLEEDING edge.
  18. 20F on the eastside of Seattle and all roads are quite throughly iced over. This morning as I pulled the RX out of the garage and down our driveway the traction portion of VSC was hard at work. A short distance down the road I had to back up a slight incline but the RX was no go even with traction control active and the rear wheels driving. After a very short period of trying to back up the incline the CEL came on along with VSC fault indication. Now I had no traction control as an assist and all I could do was spin the front wheels. So I got out and disconnected the battery for a slow count of 30 and sure 'nough the fault indications were off and I was able to more gingerly, with traction control now again active and clearly being of some help, back the RX up the incline and be on my way. For the moment I suspect the CEL was/will be the result of a too lean mixture, itself resulting from the extended period of engine dethrottling by the traction system. I'll hook up this scan gage after I get back home this evening and post the results. P0500 "Vehicle speed sensor" Apparently the yaw sensor/accelerometer was used to compute that the vehicle wasn't moving as fast as the speedometer was indicating.
  19. Sorry, I disagree. I'm quite sure that by the time my 2001 AWD RX300 was built Toyota had adopted a higher capacity/volume ATF pump to assure that a sequential downshift (following an upshift resulting from a full lift-throttle event)would be completed within incurring an inordinant level of clutch slippage/wear. I don't doubt that having a 99 or possibly even an '00 AWD vs 2WD would accelerate the the failure mileage of the transaxle but I strongly suspect that both have the core problem that results in premature transaxle failures. For the '01 - '03 models one must be careful and not allow the ATF to degrade and then after '04 there is the issue of the 1-2 second throttle lag, safety issue, to contend with. WWest - I'm just curious. When was your 01 built and how many miles do you have on it? Hearing what you say is very reassuring to me. Have to check the build date but otherwise ~62,000 miles. This morning I must go out to the garage and install all four tire chains, second time in 6 weeks, so we can go to work and get groceries. 20F outside at the moment and roads are iced over.
  20. "...it blew the main fuse causing the car to run on battery only..." Seems highly improbable.... The back up lights are separately fused and it seems to me that fuse would always blow first. Insofar as I know there is NO fuse between the alternator output and its connection to the positive battery post.
  21. Sorry, I disagree. I'm quite sure that by the time my 2001 AWD RX300 was built Toyota had adopted a higher capacity/volume ATF pump to assure that a sequential downshift (following an upshift resulting from a full lift-throttle event)would be completed within incurring an inordinant level of clutch slippage/wear. I don't doubt that having a 99 or possibly even an '00 AWD vs 2WD would accelerate the the failure mileage of the transaxle but I strongly suspect that both have the core problem that results in premature transaxle failures. For the '01 - '03 models one must be careful and not allow the ATF to degrade and then after '04 there is the issue of the 1-2 second throttle lag, safety issue, to contend with.
  22. How, where did you learn about the baking process...?? Very interesting for me as I would like to remove the red lens inside my RX300 tail lights.
  23. Before, long before, Toyota finally stepped up the plate and admitted that they had an oil sludging problem, their witless "shills" were all saying that the real problem was most likely due to lack of proper maintainance on the part of owners claiming a problem. These "shills" continued making that claim even after the letter came from Toyota indicating that a design change was made to the engine in order to prevent sludging in future models. Those "lack of proper maintainance" claims by the witless shills continue to this very day. IMMHO Toyota is stuck between a rock and a very hard place. I have little doubt that the shift pattern/schedule change that was made to FWD automatic transaxles was done as a safety measure to lower the potential for engine compression braking resulting in loss of directional control. Undoubtedly an ASSET. But. An announcement of same would be a tacit admission that FWD vehicles were/are inherently unsafe in wintertime. Obvious that is an announcement taht would have to come jointly from ALL manufacturers of FWD vehicles. There is, of course, the not so small matter of the fact that a final solution has not yet been arrived at. Until that happens I doubt that you will see any recognition of the transaxle problems.
  24. Why, how, would you have backup light on long enough to melt the lens?? Towed back to Lexus...??!! Did they give you a detailed explanation?
  25. No, retired from the legacy computer manufacturing business.
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