Juddering

[eastern lexus]

Hi all
As the tittle suggests I have this weird juddering problem that happens when I accelerate whilst moving its not the clutch.
It started about a week ago after my car sat unused for a couple of weeks it was really hard to start and when it did it didn't seem right.
When the fault occurs it is as if it is not firing on all the cylinders and really struggles to pick up .
It doesn't happen all the time but it is really bugging me.
I saw somewhere that bg44k was good so I put a can of that in but it hasn't made any difference.
Could it be coil packs or something else ?
Any help would be greatly appreciated as I am in no way a mechanic.

Edited October 1, 2013 by IanS200
merged other thread into this. same subject.

[steve2006]

Is your EML (Engine Management Light) illuminated, even if it is not the 1st course of action is to read the diagnostic codes which will hopefully point you in the right direction.

Any half decent garage should be able to do this for your for £20-30.

Once you have the codes post them up and we can offer further advice, without them it's guess work which works out expensive.

[eastern lexus]

I don't have any eml light on

Will get a code reader from work tomorrow but don't know if it will show any fault codes as eml not on or will it ?

[steve2006]

There could be stored codes so always worth checking also the EML may not come on until a specific fault has occured a certain amount of times in a period of time.

Otherwise a single glitch could throw a code.

[eastern lexus]

OK will get a code reader on it in the morning

Cheers

[eastern lexus]

Right had a code reader on it first thing and no codes showing up at all

[ChrisIS200SportTTE]

Right well check the basics... Fuel, spark and air.

Take your Airbox apart and clean it. When we're the spark plugs last changed? Long time or don't know then change them. And finally put a some decent petrol (not supermarket and maybe 97 or 99 ron) and maybe that bg44k stuff and see if that helps.

My money tho if I was a betting man would be spark plugs. Just had a friend who had lumpy idle and a hesitation under acceleration as you're describing in his IS200. Changed the plugs and it's back to normal. He also had no fault codes or lights on

[lexus loon]

Try a diagnostic test mate,bg44k is for cleaning the fuel system,also try cleaning the throttle body.

[ChrisIS200SportTTE]

He just said he ran a diagnostic and no fault codes^

[eastern lexus]

OK so going to get a new set of plugs just as a precaution any suggestions on what ones to get ?

[ChrisIS200SportTTE]

You must use iridium. Denso SK20's are oem. NGK iridium are good, I have them in my car :)

[eastern lexus]

Cool I will grab a set asap and give them a try fingers crossed

[lexus loon]

Chris ,i used the other thread and didnt see you had answered him,ive had iridium plugs on from 70,000 to 136,000 miles and still going strong.

[ChrisIS200SportTTE]

Yeah irridiums can last up to 100k but that's not saying they will. My friends IS was on 130k and the plugs we removed had to be factory fitted... They looked old and very tired!!

[eastern lexus]

Right so I have changed the plugs to nice new NGK irridium ones but still no joy

Also changed the air filter while I was at it.

Any ideas folks as its really starting to bug me now.

[eastern lexus]

Right so I have cleaned the throttle body now and still not sorted my problem grrrrr

Any suggestions as to what to try next?

[Lance]

Have you tried new petrol? If the car was lying up for a few weeks it may have become contaminated with water from condensation forming in the tank. If you havent already it might be worth a try filling the tank with some new petrol.

[eastern lexus]

Yeah its had a couple of tanks in it since then I do a 60 mile round trip each day to work and back .

[Mr.Rudus]

its either something to with bad fuel or cam timing.

check them both out -

[eastern lexus]

Right so its gets stranger my oil level light came on this morning for about 5 seconds and then went off any ideas?

[Mr.Rudus]

check your oil level. its either way too low or high.

and the above I mentioned ^

[eastern lexus]

Checked the oil level its bang in the middle of the upper and lower levels

[Mr.Rudus]

you oil level is ok.. you say the fuel is fresh and fine. have you checked the timing yet ?

[eastern lexus]

Its in the garage at the moment trying to diagnose the fault .

fingers crossed it wont be anything too serious.

[MI_LEXX]

Hi mate, I had the same problem with mine. Changed plugs, coils, leads etc but was still having the problem.

Found out that the timing belt had slipped one tooth and had put the engine out of sync. Take the plastic cover off

and see if it looks a bit knackered.