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Discussion Starter #1
Hi...new guy to the board, hope I'm not being rude by jumping straight into the question...I was coming home from a long road trip and as usual decided to give my xB (2005) a little burst of speed my clicking the O/D button (my transmission is automatic)...a few seconds after doing that I noticed smoke coming from the back...I clicked the button again and everything was cool...any ideas what may have caused that...I also have a problem with the engine making a "knocking" noise whenever I come to a stop (brake) when the car is not in park (ie @ a red light)...this car is fairly new and I want to keep it running that way...I only have 30,000 miles on it...thanks in advance for any help anyone can offer...:)
 

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OUCH !

Now with that being said, what color was this "smoke"?
Was is black, sooty looking ?
Was is blue/grey ?

If it was black sooty, it could have been just the carbon build up being cleaned out by the sudden burst of speed. I was taught to "clean" my plugs and combustion chamber by stomping on the gas occasionally by a mechanic of 50 some years. If so it is just crud built up from not driving with a lot of gusto and can be considered "normal". It is known as blowing out the carbon.

Now, if it was blue/grey could have been oil blowing passed the rings,valve guides.If it continues see your "doctor" about running a compression check.

Our motors seem to have an enheirted (sp) clacking noise, it is a quiet clacking noise in the valve train. Again if it really is trouble some for you, take her in to check her out. With 30k miles it should be ready for a check-up anyway. I believe that about the mileage for the first tune up, plug change, brakes and such. You might look into which oil was used at your last oil change, it may be a little thin.
 

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Discussion Starter #4
Thanks a lot fellas...the smoke was grey...and it may have something to do withe 4 quarts I just added *shrugs shoulders* I'm not exactly sure...but I used Castrol 5W 30 based on the advice found in another thread...:D ...and yes it's most definitely time for a tune-up...
 

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Maybe I'm missing something here, but from your first post, you mention a knocking noise. Your last post you mention you added 4 quarts of oil. Was this an oil change? Need more info.

To address another post, there won't be much carbon buildup in an electronically FI engine because the computer has such a tight reign on the engine to meet EPA specs. Unless you're burning oil of course.
 

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Discussion Starter #6
Maybe I'm missing something here, but from your first post, you mention a knocking noise. Your last post you mention you added 4 quarts of oil. Was this an oil change? Need more info.

To address another post, there won't be much carbon buildup in an electronically FI engine because the computer has such a tight reign on the engine to meet EPA specs. Unless you're burning oil of course.
I bought 4 quarts of oil and just poured it in...no oil change...I was experiencing the "knocking" sound way before that though...the oil was added last week Saturday or so...I've been hearing the knocking sound for a couple of months now...
 

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I bought 4 quarts of oil and just poured it in...no oil change...I was experiencing the "knocking" sound way before that though...the oil was added last week Saturday or so...I've been hearing the knocking sound for a couple of months now...
Your engine is not doing well. If you can pour 4 quarts of oil in your xb, it had very little oil. The engine is knocking because the rod and main bearings are gone and no doubt the crank, cam and cylinder bores are scored. As you said, I'm sure it did knock for several months.
 

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Discussion Starter #8
Your engine is not doing well. If you can pour 4 quarts of oil in your xb, it had very little oil. The engine is knocking because the rod and main bearings are gone and no doubt the crank, cam and cylinder bores are scored. As you said, I'm sure it did knock for several months.
Please do not take this as a "challenge" but I am genuinely curious as to how you are so certain about your assessment...is this a problem that can be handled with a tune-up...how much do you think it would run to fix the problem(s)...what short/long-term problems does this present for the ride? Thanks...
 

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Ok, I'm no mechanical expert, but lemme see what I can come up with.
1. If you are driving around with 7-8 quarts of oil in your motor, you're going to have a lot of problems. Sluggish running, stalls, blow-by (the blue/grey smoke you saw) among others.
2. Knocking from the motor could possibly be detonation from cheap/poor gas or misadjusted timing.

I dunno, man. Bottom line is that your car is in need for some maitanence. Have you been keeping up with your scheduled maintanence? Changing your oil every 5K Miles? With 30K on the clock you are still under warranty if you bought your car new. take it into the dealership and let them look at it. If they find that the problem was due to lack of you taking care of it I'm not sure if they would honor the claim or not. I hope that you can get your car taken care of man, it'd be a shame to see a toaster die so young.
 

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Thanks a lot fellas...the smoke was grey...and it may have something to do withe 4 quarts I just added *shrugs shoulders* I'm not exactly sure...but I used Castrol 5W 30 based on the advice found in another thread...:D ...and yes it's most definitely time for a tune-up...
yes...it MAY have something to do with that. :eek: what does the level on your dipstick read?
 

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Your xb holds 4.7 quarts. If you were low on oil and had to add 4 quarts, that means you had 7/10 of a quart of oil. That's not good. It means an engine teardown, lots of machine work and lots of new parts. Figure $3-4000 dollars minimum.

If you added 4 quarts and had 4.7 quarts already, figure you probably blew all the seals and gaskets. Engine will be leaking like a sieve. Engine teardown and new gaskets will probably be $2K or so.

Since you didn't mention oil leaks, I assume you ran the engine low on oil. When you do that, engine knocks are a dead giveaway. You'll get main and rod bearing knocks and wristpins clicking along with piston slap. The piston rings lose their temper and you burn oil.

I ruled out engine knocks due to bad gas because it would have to have been really bad gas for the knock sensor and computer to have not compensated for it. If the knock sensor or O2 sensor had failed, you would have received trouble codes on the display to the right of the speedometer. In addition, you mentioned this problem has been going on for several months.

Whatever the problem is, you need to visit a mechanic asap.
 

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Nice price on that eBay item. :)
 

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Fuzzle is dead on, your motor will knock a lil when low on oil, it's a warning you need to heed! Gas shouldn't be a problem unless it's bad (water) then you will get hesitation and rough running. I sure hope you didn't run that thing with .7 quarts of oil.......
Anyways Good Luck to ya :cool:
 

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Take it to your local dealer and have them check it out. You may be walking soon if you don't. Heck, judging by what I think may be going on (nearly blown engine), you may be walking soon anyway.
 

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Discussion Starter #18
Yeah the "maintenance" light finally came on (how come it never came on if it needed oil that badly) so I'ma have to suck it up and get it looked at (money is an issue)...the knocking sound only occurs when I make a stop in transition it doesn't occur as I'm driving or when I'm in park...anyway thanks for the help/advice and HNY to everybody!
 

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Post back what you find out.
We can do alot of guessing, but we can't be there to look and listen like the dealer can.
 

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Yeah the "maintenance" light finally came on (how come it never came on if it needed oil that badly)
The maintenance light is only a "timer" sorta thing. It only comes on every 5000 miles to remind you to change your oil.
 
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