My 20V SVT idle sucks, need help...

[shizilki]

Good day to all Toyota members,

Need help to identify what's the cause for my engine bad idling. When i start cold, the RPM doesn't ram high then goes stable like it should. The needle just crawls slowly. Another thing is the idling never maintained. Sometimes 1.2k, 1k, 1.5k, below 1k isk...isk
i fren of mine said maybe autochoke problem. i got no idea where this is located. So, really need help from all sifu's out there

Thanks a bunch

 

[scottwrx]

of you have juz restart you ecu, then it is normal..
but if there is not the case then u need to check your tps or your engine head.. have u done any port n polish??

 

[danny_rigid]

idle valve is below the 4th intake plenum........a very hard thing to replace! Make sure check everything first!

 

[TRD.AE92]

ISCV clean already?

 

[banzai]

clean your ISCV and throttle body. take it out individually and run it through with a good carb cleaner & petrol. you will feel the difference.

 

[suma_]

try swap AFM with a good one. AFM is very prone and for aging SVT, it can be the main culprit.

 

[shizilki]

port n polish done along with throttle body, maybe i'll try resetting the ecu tomorrow.
ICSV, very hard to pull out, tried it before.
AFM....mine just being serviced & adjusted last month. Mechanic said still functioning well
Anything on the autochoke?

 

[levin818]

At stock setting, when you start the 20V, the rpm should goes up to ~1200rpm and stay there, if it is at cold start, or bounce back to ~800rpm, if it is at working temp. If your rpm climb up slowly, then its your ISCV is dirty. You need not pull out the ISCV for cleaning. I think Chinozie has some good idea to clean the ISCV without pulling it out. ((( Paging Chinozie ))). You are wanted
As far as i concern, the Throttle Opener that attach behind the 4-throttle act as auto choke. Before vacuum is exist (before started the engine), it slightly push open the butterfly, just like the paddle is being push down slightly. When vacuum is exist, it let go the butterfly. There is a screw to adjust the opening angle of the butterfly. Some tuner use this screw to bypass the ISCV and control the idling. But by doing this way, TPS need to be re-adjust together.

 

[levin818]

Adjust Throttle Opener - refer to BT service manual EFI pg.53

 

[shizilki]

wong is it? u sold me the svt ecu before. we met at petronas station near kota kemuning. i'm going to Puchong tomorrow, maybe can meet u to troubleshoot what's the problem is

ecu resetted, still the same
maybe i'll go for ISCV after all
Thanks for the info guys

 

[levin818]

Hi Shizilki, yes its me
If the problem never resolved, no matter how many times your reset the ECU, it will come back.
I'm worried i can't meet you tomorrow coz i'm leaving to JB on tomor morning.
Next Monday is Ok?

 

[cruiser78]

port n polish done along with throttle body, maybe i'll try resetting the ecu tomorrow.
ICSV, very hard to pull out, tried it before.
AFM....mine just being serviced & adjusted last month. Mechanic said still functioning well
Anything on the autochoke?

I think SVT or BLT dont have autochoke. Autochoke only can be found on carburetted engine which has a water line going into carburettor. Autochoke function is determined by water temperature. 4AGE have its cold idle control system by using its ISCV. ISCV opens or closes according to water temperature too but it also uses other value such as aircond signal, throttle position, intake air temperature and some other things too, just my thought...

 

[shizilki]

Hi Shizilki, yes its me
If the problem never resolved, no matter how many times your reset the ECU, it will come back.
I'm worried i can't meet you tomorrow coz i'm leaving to JB on tomor morning.
Next Monday is Ok?

hehe i'm at KL for only 1 day today, tonite going back to t'ganu. Sudah serabut la dgn idling tk betul ni

I think SVT or BLT dont have autochoke. Autochoke only can be found on carburetted engine which has a water line going into carburettor. Autochoke function is determined by water temperature. 4AGE have its cold idle control system by using its ISCV. ISCV opens or closes according to water temperature too but it also uses other value such as aircond signal, throttle position, intake air temperature and some other things too, just my thought...

thank you for sharing, maybe need to send back my car to my mechanic at balakong to adjust the TPS n also clean the ICSV

 

[FGT]

of you have juz restart you ecu, then it is normal..
but if there is not the case then u need to check your tps or your engine head.. have u done any port n polish??

do u know any good workshops around pj or damansara to do port n polish + throttle body + injection service for 4afe?

 

[pcmoddingmy]

shizilki: I think maybe just change the throttle body with another one. Might help resolve your issue if you cant find anyone to set it properly. If can, try to post up a video of you engine RPM when starting up until idling.