i used some of fuel injector cleaner and it helped a bit. mine seems to go thru spasms of rough idle, which usually subsides after some driving. I might check the maf too if there is a DIY about.

 

in my opinion. all 4 banger cars idle rough. to me anyways. working for BMW and watching I6's and V12's run 4 bangers run like crap from the factory. this is just my opinion.

 

my xB runs really smooth even when the idle drops to 650 rpm - just sits there making a hissing sound without any vibration at all. Weirdest sounding engine I ever heard because of the VVTi. Of course you haven't felt smooth until you drive a 3 cylinder.

 

Well, i installed some irridium plugs and reset the ECU and it really smoothed out my rough idle. I have Randode's ground wire kit on the way, so hopefully that'll be the icing on the cake.

 

Check the sprark gap on the old plugs and see if that are gapped way too big. Be good to know what cause the problem too instead of just what solved it.

What's really weird is that my xB just this past week has started a lot quicker that it usually does - I don't know if the ethanol has evaporated out of the almost empty tank of gas after a month or what but I filled up yesterday and will see what happens when I start it up next.

 

any new info or insight? My idle in D is sh!tty and really driving me insane.

 

definitely check your plugs. i was overdue on plugs and it ran so rough. but i changed them with Toyota plugs gaped them to spec and it ran like a inline 6 would. smooth and easy.

 

plan on doin that next month, im due

 

Fuel, Air, Spark are needed to run an engine plus with ours proper valve timing. If injector cleaner helped a little then you need some more to keep it running smooth. Tail pipe clean or sooty - oil burning a little will foul a plug depending if the idle is rough or skips randomly will indicate a single plug misfire or maybe a general fuel problem or an air leak in the intake. You could try driving down a steep hill in first or second gear getting the rpm up to 4000 or so with no gas and see if it idles worse after that. It could free up a stuck VVTi adjuster in case it is not working properly or suck more oil in to the bad cylinder and really idle rough after that. When in gear idling smell the tail pipe for unburnt gasoline - indicating a bad spark / plug. Usually you can't see oil burning any more because the cat cleans it up but you can still smell it a little and see the oil going down on the dip stick between oil changes.

 

hmmmm yea im pretty sure the dealership took your $300. Valve adjustment on a Toyota??...

 

sounds like a vacume leak. check your intake piping couplers, also pull the maf sensor and make sure the o-ring is seated properly, put oil on the o-ring to re-install and make sure it isnt getting pinched.

 

did a lil research. the only way to adjust valves on our motor is to pull the cams off and shim each individual valve spring bucket.... this would take a day to do. Dealership would charge around $900 to do. It should never have to be done though, so what I am saying is the dealership bs'you unfortunately. I would go back there and ask them how they actually adjusted the valves lol.

 

yeah really the valves are so short and straight from cam to seat that there should be NO WEAR unless something is seriously wrong and they should not need adjusting. Now if they are hung up on carbon deposites and they readjust them . . . that is going to cause real problmes when that carbon blows out and you have valves stuck open all the time.

 

Alright for all of you experiencing this: I have an xB and so does my mother. and only she has had this problem. I am a Toyota student and also a Toyota tech. When my mothers started experiencing the problem I took her car back to the dealer we got it because it was still under warranty therefore I wouldn't have to take it to work. Well needless to say they gave up on it. So then it got handed over to me and I proceeded to mess with it for the entire summer had narrowed it down to a lazy O2 sensor so I then changed that and it fixed the problem for only a short period. I then asked the Toyota field tech for my area and he hadn't heard of the problem yet so after looking into it he still found nothing either. If I find anything else out about it I will let you know and if anyone finds anything please let me know. It seems to be an issue that some xBs have because i have driven many with the problem and many without. Also for the one that got the valve adjustment, Toyota engines are never out of clearance especially not at 50,000mi. so my advice for you never ever go back to that dealer again. All this info isn't very helpful but it is all that I have found. If anyone figures anything else out that would be great.

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You you people with the rough idle and O2 sensor problems - what engine oil are you putting in there. Fuel and Engine oil all burn and come out the tail pipe and since the fuel is pretty well controlled that leaves the oil. Also it doesn't help to "pump" the gas pedal - it really confuses the FI and can cause all sorts of weird things to happen - nice smooth gas pedal use and the engine should run nice and smooth. Half a bottle of STP gas treatment from the RED plastic bottle does wonders too.

 

I tried that downhill thing Jan06 and it was still somewhat smooth

It's odd that my manual in neutral shakes more than my wifes auto in neutral.

when I drive fast past 3k my car will run rough though if I keep slow it runs better.

htough I can still feel the shake especially on my driver door when its open.

 

That really sounds like something is not quite right there and a can of starter fluid may tell the story if there is an intake leak. You spray the starter fluid around the intake fittings and gaskets - you probably could even use a spray bottle with water that squirts a stream. When the air leak gets the starter fluid the engine gets more "fuel" and runs smoother or in the water case the small air leak gets plugged with water for a second and the engine smooths out or stumbles as the water gets sucked into the engine. either way what you are looking for is a change in the engine idle when you hit the leaking spot. BTW water is not going to start a fire in the engine - just don't drown the engine with too much water - don't use a garden hose. A leak at 3000 rpm could happen if the engine vibration is causing the intake to vibrate at that speed and opens up the air leak. Another thing to check is the tailpipe and listen to the exhost and if it has a regular skip then it is one cylinder like an injector or gasket at the head but if it is random then it usually indicates a common to all cylinders problme - further out on the intake closer to the air filter or a problem with the fuel.

 

Well, i've had Randode's ground wire kit here since April, and finally got around to throwing it on today (simple, 1/2 hour install). HUGE improvement on Idle. Raised up from 500-600 to 700-800. Doesn't feel like it's ready to die at any time.

 

I heard this was a problem with the tC but not so much with the xB . . . makes me wonder if that may be the problem I have with irregular starting. Sometimes my engine fires right up and sometimes I have to crank it for 10 seconds but it bump starts on one or two compressions. Could be a poor ground to the frame - the negative is connected to a front frame that bolts to the rest of the car so there certainly are enough places for a poor connection to form.

 

Wife's xA was having a nasty idle as well. Checked plugs, and the norm. It ended up being 3 bad coils. Thought I'd pass it along.

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