Cleaning Throttle Body

[BigMo82]

I have found that sometimes my car doesnt idle too well and the revs drop down to about 600. It never cuts out but sometimes I can feel it vibrate. I had a similar problem with my old Astra and cleaning out the throttle body sorted it.

I have been told by someone that the Avensis has a electronic throttle body and these should not be touched otherwise the setting goes off. Does this sound right?

On the Astra I just removed the air flow pipe, held the butterfly open and cleaned out the inside with a cloth and carb cleaner.

Mo

[frankie406]

hi bigmo i cleaned mine out too yesterdayon an 03 1.8vvti avensis just done wat you said on your astra.dunno if the 2.0 is any different? i also took out pcv valve and cleaned it too..

[BigMo82]

Thanks for the reply Frankie. Can I ask is your 2003 a T25?

Mo

[frankie406]

yes mate it is!

[BigMo82]

Thanks Frankie going to give it a go tomorrow.

Mo

[frankie406]

try cleaning pcv valve too mo .dunno where it is on 2.0 but mine was on top end of engine right hand side looking into engine...theres a hose that comes from it into the exhaust manifold..the valve on mine was taking out with a 19mm deep socket..cleaned out and put back in with a wrap or two of plumbers p.t.f.e tape..hope that helps!

[+robster+]

interesting regarding the pcv valve making a difference

our mitsubishi forklifts have nissan k21 engines fitted

they have a pcv plumbing on them.

if you have the engine idling then you remove the oil filler cap it runs like its missing a cylinder.

never thought about it too much but going to see why this happens?

another thing

ive removed and cleaned out throttle bodies on puntos (1.2) and they respond really well

probably cause its an assembly that has tps and map sensor integrated into it.

cleaning out will give map sensor a better reading ( no maf on these engines)

[frankie406]

yeah after cleaning theres alot of difference.even mpg has gone up and seems to be a bit more power..???

[Vlado P.]

i have recently cleaned the throttle body on my avensis 2.0 vvti, having previously had the same rough idle, dropping to below 600 rpm. the car felt like it's gonna choke when warm.

the throttle body didn't seem very dirty, although there was some gunk on the throttle wall and the butterfly itself. after cleaning, i noticed immediate improvement!

i wasn't very happy flushing that gunk and crap through the injectors, however it seems that if you remove the throttle body, the throttle position sensor would have to be re-calibrated (which i don't want to do).

[IRL Techie]

Lads,

Does this apply to the 1.6 Petrol T25 too?

[Vlado P.]

most probably!

[citam]

Hi,

I also cleaned throttle body on my Avensis 2.0 VVT-i '03. Throttle body was removed before cleaning. Now car is reving up and has in IDLE about 1.400 rpm.

You were talking about re-calibration of TPS.

How the procedure goes?

[Pete W]

Did you manage to find out how to recalibrate tps ?, and why does it need to be done.

[citam]

@Pete W: look at post No. 9 why to recalibrate.

I did not find out how to recalibrate, but revs seems to be fine now. They droped to about 800 at idle after cca. 500 kilometres of driving.

[Pete W]

Hi, i read post 9, but it doesn't say why you would need to recalibrate. If you are just taking off the throttle body, and putting the same one back, why would you need to recalibrate. I would like to do mine, but i am trying to find out what it does if you remove it. Also would it reset itself if you disconnected the Battery for 30 mins like other things. thanks.

[Vlado P.]

it does not seem logical to me too, but judging from other people's experiences it is an often occurrence. it's probably why almost none of the DIY tutorials on the web does not advise removing the TB, instead they all clean it in situ.

[frankie406]

i cleaned mine a year ago i when i bought the car had no problems..done a service on car a few weeks ago and recleaned the tb had no problems again!! UNTIL today mines is now sitting at 1350/1400 when hot but and blip on the pedal and drops to around 650/700 RPM.tried cleaning the port into the TPS on the TB.but nothing also tried to reset ecu by taking off the Battery term!

[frankie406]

update** took TB off car today cleaned the port into the icv sensor and took of tps sensor cleaned also and cleaned the butterfly valve..put all back again the put key in ign with engine off! turn the key but dont start and count 10seconds do this 3 times.

mine now sitting @ 700rpm.

[BigMo82]

Frankie has your idle remained at 700?

Mo

[frankie406]

yes mo still sitting nice @700rpm :-)

[BigMo82]

Does it ever drop down to 600rpm?

Mo

[Avensis Avenger]

I had the throttle body cleaned earlier this year as my (automatic transm) engine kept cutting out when pulling out onto roundabouts which was scary!

I was suprised at the uber high idle that resulted from cleaning the throttle body. Still, when starting, it idles at 1500 odd. Over a period of time it does settle back to 600/700. Must use a fair bit of fuel.

[Vlado P.]

yup! them seem to like high idle rpm when cold.

mine even goes above 1500 rpm, however the car was really choking before cleaning the TB.

[BigMo82]

A lot of people say there cars are idling at 600 but isn't that a little low for a 2litre car? I would have thought 750-800 is the ideal setting.

Mo

[Vlado P.]

actually, the ideal idle is around 650 rpm. at least on my car. lower than that and vibrations start to develop