Help! My sc300 drives rough and has white smoke that comes out on occasion
#1
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Help! My sc300 drives rough and has white smoke that comes out on occasion
About 6 mos back the car lost idle and would not hold an idle so I garaged it b/c I had to go to CO and renovate my rental house. It was garaged for like 6 mos and when I came back I took it to a local mechanic who did a tune up and and put in some new oem o2 sensors ($163 a piece mind you). The car still drove rough and would not hold hold an idle at first of the day start up, have to warm it up for a while for it to hold idle, and it has a very low idle at that. So I took it to the Lexo dealership and they found a hole in the intake hose, relpaced it ($200) but it stil drives rough and now a big gust of white smoke comes out sometimes and the engine will vibrate heavily. Lex Dealership said it would cost another $300 to dig into the catalitc conv and engine, I said forget it-already dropped $1500 . The car has 221k on it but drove beautiful prior to me losing the idle 6 mos back. I posted this prob on a expert forum and a lex mechanic said it sounded like a blown gasket and I should perform a leak test. THe car does not leak oil . Anyone have this prob or know what te prob possibly is? YOur help would be appreciated.
The 07 ES 350 loaner car for a a few days was pimp
The 07 ES 350 loaner car for a a few days was pimp
#4
he probably ment that the headgasket was leaking and to do a compression test like em said or a cylinder leak down test to check the internals of the motor sometimes you can take out the plugs and look in the cylinders for coolant but if theres milky oil or collant its probably the headgasket
#5
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he probably ment that the headgasket was leaking and to do a compression test like em said or a cylinder leak down test to check the internals of the motor sometimes you can take out the plugs and look in the cylinders for coolant but if theres milky oil or collant its probably the headgasket
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#8
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I drove it today and for the most part it drove pretty smooth as of old times but when you stop and accelerate the RPM dips a lil with a very slight hesitation. The main problem seems to be at start up, you have to warm it up or it will just cut off/ drop to a very low idle. Once it gets going it seems to be ok but still has a pretty low idle. Hasn't done the james bond smoke screen today or yesterday lol. Do you guys still think it's the head gasket, even though it drives smooth most times? Seems like if it were the headgasket it would ALWAYS drive rough and produce a white smoke screen. I hate to get rid of it b/c unfortunately I just dropped on brand new oem lca's last month and ps pump + alt a couple of years ago, new steering rack a couple years ago and had the seals redone to stop the oil leak ($700 mind u). The car doesn't leak not a drop of oil. It's mechanically sound, body real clean. It was sitting for 6 mos maybe it just needs to be readjusted by driving it out? I just bought a 98 sc 400 w/71k ...but I hate to part w/ the 300
What would u guys do? How much would a new notor and swap cost roughly?
What would u guys do? How much would a new notor and swap cost roughly?
#9
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No my car drives smooth again with no smoke ...wtf? I don't think it's the head gasket afterall...no signs of head gasket failure from what I read even though I didn't do a compression test, the Lex mechanic never even mentioned the possibility of a h -gasket failure. Hopefully all good. It has been sitting for 6 mos so maybe it's readjusting.
#11
Is the "check engine" light on? If so pull codes and go from there. If not. Do a compression test (you can get a compression guage at a tool store for cheep) Max should be 185psi (or more). Min should be 156psi with no more then 14psi difference between cylinders. Rember to remove the coil wire when doing the test so the motor will not start. Do it when the motor is at normal operating temperature.
Last edited by 2JZ_SC; 12-28-06 at 06:56 PM.
#12
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Is the "check engine" light on? If so pull codes and go from there. If not. Do a compression test (you can get a compression guage at a tool store for cheep) Max should be 185psi (or more). Min should be 156psi with no more then 14psi difference between cylinders. Rember to remove the coil wire when doing the test so the motor will not start. Do it when the motor is at normal operating temperature.
#13
See if the throttle plate is dirty. If it is clean it and the body and go from there. On some of the newer "fly-by-wire" cars the throttle motor was out of adj and that lead to a low idle. I would clean the throttle body first and see if that fixes it. Carbon can build up on the plate and make it stick and or not let all the air that the enging needs into the engine. Good luck.
#14
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See if the throttle plate is dirty. If it is clean it and the body and go from there. On some of the newer "fly-by-wire" cars the throttle motor was out of adj and that lead to a low idle. I would clean the throttle body first and see if that fixes it. Carbon can build up on the plate and make it stick and or not let all the air that the enging needs into the engine. Good luck.
thanks. where is the throttle plate? Is there a diy thread on this?
#15
The throttle plate is inside the throttle body. Get some throttle body cleaner in a spray can from the parts store. Remove the intake air tube from the air box and the throttle body. Hold the throttle open with your hand and spray in-to the body. Try to clean the backside of the plate and where it seats in the body. The front of the plate and the body should be clean (if your air filter is doing it's job). On the back side is where the carbon will build up. After it is as clean as you can get it, Hold it open for about 30min of so to let the cleaner evaporate (use a screwdriver in the LINKAGE, DO NOT weg anything in the throttle body itself. Some pepole will put a brick on the gas peddle to hold it open). Reinstall the air intake pipe and try to start. It will be hard to start (some times VERY, Depending on how much cleaner was used). After it starts it will run ruff for a little bit and then smooth out. This is part of a major service and should be done about every 30k to 90k (I do mine every 15k) hope this helps.