lexcalibur300

Back-on-the-block journey through time: CZ motocross 250cc 1955 Ford 292 1956 Ford 312 - big Holley carb, T-bird engine 1960 MGB Twin Cam (Had to carry spare jets to change side drafts mixture going thru Smokey mountains) 1940 Chev body/frame, 456 Posi, Chevy 348 cc w/Lathum Supercharger, 4 carter sidedrafts -- Awesome street jailbait! Shucks - Drafted U.S. Army and off the street for 1 year, 9mos, 21 days and 14 hours! 1966 VW Sunroof 1966 MGB 1966 mid-year Dodge Charger 360 fastback 1973 Dodge Charger 383 1970 Mercury Capri 1972 Chevy Van 1976 Ford Elite (Two door, loooong hood, plush white leather, beautiful "Turnpike Cruiser") 1984 Supra straight six (slam you to the seat excelleration and handling -- precision engineering ahead of its time). 1987 Ford Thunderbird 1987 Honda Accord 1988 Toyota Celica Convertible 1988 Mazda B2600 Truck (5 inch lift and big tires) 1989 Trooper 1998 Honda Accord 2000 SC 300 Whew -- a lot of highway miles and have loved every one! Note: Still have the truck for the woods, the Celica convertible as the closest my wife will let me get to a motorcycle, and the Lexus for class. Remaining surviving vehicles distributed between three kids and their spouses. The Lexus, by far the most intriguing ride that still stirs the soul everytime on a road trip! Truly, precision work-of-art on wheels. The SC is a keeper! Thx to all for learning so much on this site ...Lexcalibur

Hey Lexxus, Whatever happened about the "engine rattle knock" in your girlfriends car? Ever determine exactly what is causing it? I know you went through some challenges with both cars. Any resolution with prior owner? Good to see you haven't lost faith and looking for another one -- good idea to find another that has been well taken care of with low mileage. Take care and good luck...Lexcalibur

For budget considerations, replace the low beams first as they are easy to access and replace with just a few minutes effort. Purchase the high beam model of the bulb (does not have cap on tip of bulb and is rated 10 watts higher). Cut or file off the two tiny ribs where the assembly plugs into the harness plug. Your low beams will now look GREAT -- one of the easiest, cost effective and best results of any lighting modification you can make. The high beams as they are may look OK to you -- you can decide after you do the low beams if you want to upgrade the high beams with Silver Stars as well. You'll use the same model bulb for both the low and high beams. You just will not have to modify the connector on the high beams -- plug and play. Or you can replace the fog lights with the appropriate Silver Star bulb in lieu of high beams for budget purposes. If money not an issue -- replace them all with Silver Stars.

Ditto -- Based upon CR report and other performance forums, I replaced Michelin Pilots with Falken Zs. The Michelins had a much more granular road feel, whereas the Falkens very smooth and much quieter. Least road noise of any tires I have previously used. In summary -- outstanding tires accordance with industry reviews.

Any progress on your girlfriend's start-up rattle? Note in the Lexus LX470/450 forum, thread regarding oil filters and comments about start up rattle: molocka12, Sept 24 Also another notation about start-up "grinding" noise: gage, Sept 24 Interesting.......

Lexxus, What specifically was wrong with ecu -- did it have to be replaced and at what cost? I think you mentioned you are limited in CA on 91 octane. Would be interesting to know if ping would go away on 93 octane available in other states. I agree -- car needs some open road time with cleaner! Also, any new development or information on the engine "rattle" saga on your girlfriend's SC300? Hey, these problems come in groups -- you're due for good ride for awhile. Good Lexus Luck...

"There by the grace of God go I..." This past year in Pensacola, FL., a young man who is a friend of our family was sentenced to 18 years in prison (mandatory minimum sentence w/o parole) for accidently killing two young women while drag racing and drinking. During early morning hours, he and a camero gunned their engines at a light -- the next fifteen seconds would terminate the lives of two women in their prime and devastate all the families involved. The young man lost control of his car and it smashed into the girls' car with such crushing impact it killed them instantly. The camero, several car lengths ahead, fled the scene. He was arrested several days later. Realistically, speed and racing are genetically imprinted for most young men. Fortunately, those on this forum can focus beyond that to the unique qualities of the Lexus Sport Coupe -- precision engineering, luxurious performance, and timeless beauty. Given the limited number on the street, truly a rare work-of-art on wheels that is ours alone. Personal pride with finesse wins every time! Good Lexus Luck...

From one "Nole" to another: Nothing quite as classy as a "Nolex" in Tallahassee. Who repairs your Lexus in Tallahassee or did you fix the ecu yourself? Thx...

Air Conditioner Compressors can vary in their smoothness based upon fit or wear condition of the shaft bearings. The reason vibration is intermittent is because the A/C triggers on or off according to thermostat temperature setting. When compressor kicks on cooling the air, the compressor bearings under significant additional load doing its job. On some cars, if the belt driving the compressor is installed way to tight, that can lead to premature failure of the bearing behind the front pulley. Normally compressor bearings wear and become rougher with age -- but they can last several years running kind of rough. New compressors should be smooth, although you can still sense when they kick on and off as a rule. There should be barely discernable vibration or noise with a new Lexus -- if so, the compressor not up to standard quality. Check brackets or mounting braces to make sure bolts are tight and that bracket has not cracked as this will cause vibration as well. Good Lexus Luck....

Summary: Seven to eight seconds of "loud knocking" on start up is extreme. Glad that suggested oil/oil filter change resulted in reducing to several seconds of "rattle" instead. But your situation needs to be resolved -- if main bearings, then they are excessively worn. Background response: If timing belt due for replacement then at least not wasted effort with your mechanic. But, if problem is sticking hydraulic lifter, then the noise you would hear most likely would be more of distinct singular loud tapping -- not knock/rattle deep within engine. Using the excellent screwdriver "listening" technique suggested by jdowen2 you can tell if localized at top end. Seems hard to believe it is just a lifter to the extent you had "loud knocking" before changing the oil. But no harm in replacing the lifters except for the dollars. Have you asked either dealer or your mechanic the cost to drop the crank and replace the main bearings and the oil pump? You could have the timing belt replaced at same time displacing some of the cost since timing belt due replacing anyway, and the harmonic balancer has to be removed to drop the crankshaft. If you are going to spend money at risk, I would suggest this is best place to spend it. Considerable cost is saved if they can do it with engine still in the car -- I do not know if possible on SC. Oil pressure -- if thorough analysis at dealer, they should have measured oil pressure given your symptons. What viscosity oil and which specific oil filter was used to reduce the time and extent of knock? I hope the problem turns out to be simplier than main bearings. However you proceed, will mechanic or dealer guarantee that their prognosis and your spending your money with them will guarantee fixing the problem? Good Lexus Luck....

Yes, replaced original Michelins with Falken Ziex 16x225x55 on my SC300 based this and other forums experience and recommendations. Also reviewed the Consumer Reports edition featuring performance all-season tires. Paid $107 each installed at Discount Tire -- much less than comparable tires I was considering. Falkens are outstanding cruisers -- smooth and very quiet. Approximately 1/3 the road noise of the Michelins at high speed. Also, prior tires had a "granular" feeling whereas Falkens are smooth -- like a Disney monorail! Keep in mind though, the Falkens are new compared to 40K on the Michelins -- but they still had considerable tread left. Having traveled some distances and through serious thunderstorms this time of year in the South, wet condition performance excellent in my view -- but no experience with snow nor a factor in the South. Performance grip may not match the Michelins, but I have not pushed to that extent to know for sure. Falkens definitely have a different feel so difficult to compare on general road conditions in lieu of test track. Also, road feel consistent with "rolling resistence" ratings in Consumer Reports -- Falkens seem to coast freely. Overall, enjoy these tires much more as they enhance the elegant road feel of the car. PS - I have usually used Michelins for all my cars in the past. Lexus luck to you...

Yes, replaced original Michelins with Falken Ziex 16x225x55 on my SC300 based this and other forums experience and recommendations. Also reviewed the Consumer Reports edition featuring performance all-season tires. Paid $107 each installed at Discount Tire -- much less than comparable tires I was considering. Falkens are outstanding cruisers -- smooth and very quiet. Approximately 1/3 the road noise of the Michelins at high speed. Also, prior tires had a "granular" feeling whereas Falkens are smooth -- like a Disney monorail! Keep in mind though, the Falkens are new compared to 40K on the Michelins -- but they still had considerable tread left. Having traveled some distances and through serious thunderstorms this time of year in the South, wet condition performance excellent in my view -- but no experience with snow nor a factor in the South. Performance grip may not match the Michelins, but I have not pushed to that extent to know for sure. Falkens definitely have a different feel so difficult to compare on general road conditions in lieu of test track. Also, road feel consistent with "rolling resistence" ratings in Consumer Reports -- Falkens seem to coast freely. Overall, enjoy these tires much more as they enhance the elegant road feel of the car. PS - I have usually used Michelins for all my cars in the past. Lexus luck to you...

Following the "saga" -- imagine your girlfriend truly appreciates your efforts on her behalf. Hopefully will turn out all this worry for nothing! I personally believe with symptons so far, the main issue (excuse the pun) is still main bearings. But is possible that reducing compression might help, but still need more background substance from mechanic to believe carbon build up is actual cause or solution relief. Definitely do not want to invest in head job for $2800 and still have rattle/knock problem of some sort! MOST RECENT DEVELOPEMENT: Latest round of issues and your immediate questions -- I am speculating what the most recent dealer/mechanic might interpret according to their findings. I know you already understand most of this, but to keep perspective here are my (non- qualified mechanic, new to Lexus engine) responses to your recent questions. We really need their detailed qualified explanations. Your questions: "How could carbon make this knocking sound?" If mechanic tested and measured cylindar compression and found compression much higher than normal specifications, their educated view might be that additional compression contributes to the loose mains knocking as the higher compression puts abnormal additional force on the lower end. That additional force might make normally worn main bearings "rattle"/knock until flowing oil gets to the bearing surfaces between the bushing surface and the crank surface. Once the oil flows between the surfaces there is no metal to metal "slapping" or noise. "Why would oil change have any effect on carbon deposits?" Because the core issue is the excessive gap between crank and bearing surface -- therefore quicker or better flowing oil will stop the rattle no matter the contributing factors. But the point you are really making is true. "And if carbon, why would it only cause a knock in the morning, and not later in the day?" Same as above -- the metal surfaces are coated sufficiently until finally drains down overnight. And your point is correct that proves it seems to be more than just a carbon issue in my view as well. "If it had really bad carbon, wouldn't that cause a decrease in power?" (In reference to how strong the engine seems.) This may be truly a case where carbon build up over time increases compression without degrading valves to the point it does in fact increase performance of an engine as long as there is not detonation/pre-ignition. If you use 93 octane that helps the engine cope with the increased compression caused by carbon build-up. You have mentioned several times how "strong" the SC 300 engine feels and the excellent performance compared to your SC400. Remember that I commented early on we use to gap main bearings loose to lessen engine friction and that contributed to better performance for drag racing. Well in this case, it could be the engine has loose lower end combined with higher compression resulting in a stronger running car performance wise. Higher compression (whether turbo driven or carbon buildup to lessor degree) increases performance, but is harder on all components -- but as I understand the SC300/I6 engine, it has been historically designed with strong lower end to accept Supra/Soarer turbos. In fact, you said it yourself, "... the car runs like a rocket.!" If the mechanic feels top end needs carbon cleaned -- what are the recommendations and associated cost? Were you able to have an in-depth discussion with dealer/mechanic to understand their view and experience with this issue. They are suppossed to be the experts -- but do understand you have had several different opinions on same issue. But a sit down give and take with mechanic may be helpful to each of you to come up with definite conclusion. BACKGROUND ISSUES: How strong and for what duration is the "rattle/knocking" on start-up? You mentioned changing the oil improved the main bearing rattle. What viscosity weight oil and to what extent did it make a difference/change (one/half second, one second, one and a half second etc) from engine start to rattle quit? What specific oil filter did you use? What is current measured oil pressure (at cold and hot) compared to what is considered expected oil pressure? If the oil pressure runs abnormally low when warm or cold, that may hint at another cause or confirm worn engine (especially main bearings). What is experience level of the mechanic who actually diagnosed your situation this time? What is your next step? One option is to drive and enjoy car with improved oil/filter and see if gets worse in near future. Apparently has been going on for a long time according to the prior owner's records. Good Luck...

Ok, got it -- the guy is either ignorant or a crook! In either case, once you have determined situation with facts you can go back and explain asking for either total refund or adjustment. If honorable person he may listen and try and work it out. Or, if a jerk throw you out immediately. Or if an outright crook, may just try and beat tar out of you to scare you off -- hey sounds like 33% chance to work it out! Do you have any way with service records or otherwise to determine if mileage is correct on the car. That is another discussion issue if does not reconcile and that gives you some leverage with prior owner. Back to the "rattle" (sounds better than knock) -- has your mechanic confirmed it is main bearing rattle? What are the mechanic's suggestions? Did he suggest it might be "quasi normal" for this engine with some miles on it? With only 84K on engine (if that is true number), what would the mechanic charge to drop the crank and replace with replacement bearings (actually curved bushing)? I do not know enough about these cars or engines to know if possible with engine left partway in car or if whole engine needs to be removed. If it is mainbearing rattle, what kind of oil filter has been in the car? If "El Cheapo", next step is the correct oil filter with a valve retaining oil in the filter for immediate supply to the engine on cold start. I did see your inquiries about the appropriate part number on the forum. Note, seems like Lexus dealer would have put in the appropriate filters in the past, but could be prior owner was using a quickie lube for his oil and filter changes and they provided another type filter. Are you going to try 5W - 30W oil to see if helps get oil to bearings quicker? Of course, without knowing current type of oil in the car difficult to know if will make a difference or not. Johnny3 response as a mechanic is interesting view that he did not think bearing replacement was necessary nor would fix the problem. Hopefully, he'll explain further. I do agree that main bearing rattle may not be as bad situation as it seems right now until have tried some things. Keep us posted -- without knowing current oil and filter, my hope is engine responds to thinner oil and better designed filter. Good Luck....Lexcalibur300

Ok, got it -- the guy is either ignorant or a crook! In either case, once you have determined situation with facts you can go back and explain asking for either total refund or adjustment. If honorable person he may listen and try and work it out. Or, if a jerk throw you out immediately. Or if an outright crook, may just try and beat tar out of you to scare you off -- hey sounds like 33% chance to work it out! Do you have any way with service records or otherwise to determine if mileage is correct on the car. That is another discussion issue if does not reconcile and that gives you some leverage with prior owner. Back to the "rattle" (sounds better than knock) -- has your mechanic confirmed it is main bearing rattle? What are the mechanic's suggestions? Did he suggest it might be "quasi normal" for this engine with some miles on it? With only 84K on engine (if that is true number), what would the mechanic charge to drop the crank and replace with replacement bearings (actually curved bushing)? I do not know enough about these cars or engines to know if possible with engine left partway in car or if whole engine needs to be removed. If it is mainbearing rattle, what kind of oil filter has been in the car? If "El Cheapo", next step is the correct oil filter with a valve retaining oil in the filter for immediate supply to the engine on cold start. I did see your inquiries about the appropriate part number on the forum. Note, seems like Lexus dealer would have put in the appropriate filters in the past, but could be prior owner was using a quickie lube for his oil and filter changes and they provided another type filter. Are you going to try 5W - 30W oil to see if helps get oil to bearings quicker? Of course, without knowing current type of oil in the car difficult to know if will make a difference or not. Johnny3 response as a mechanic is interesting view that he did not think bearing replacement was necessary nor would fix the problem. Hopefully, he'll explain further. I do agree that main bearing rattle may not be as bad situation as it seems right now until have tried some things. Keep us posted -- without knowing current oil and filter, my hope is engine responds to thinner oil and better designed filter. Good Luck....Lexcalibur300