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

[ee90kl]

bro,my svt when cold start,rpm din goes up,it around 800rpm.if i press d pedal abit,d rpm wil become unstable,goes up n down between 400 n 800,it feel like wan 2 die out.
But if i leave it warm up itself,after few mins,everything is ok n idle stable.
Juz face tis prob recently,b4 tat when cold start,rpm wil goes up to 1200.
Wats d prob?
Tq

 

[et_box]

Same problem. During cold starts the rpm is normal. Once i press the accelerator, the rpm drops and i have to press harder to compensate.

The engine feels like dying until when it has warmed up sufficiently, it becomes normal.

So strange... wonder what is wrong... Car also feels a bit underpowered too..

 

[levin818]

Idling problem at cold start - clean your ISCV + 4-throttle
Underpower - check your TPS & Timing's setting

 

[me2kimi]

What is function of the screw at AFM? I remember last time when idle suck during aircon on, the foreman re-wired aircon vsv (maybe the vsv did not switch on). After wiring done the idle still suck the he adjust the screw at afm. SO what actually the screw use for? Some said do not touch the screw.

 

[me2kimi]

What is function of the screw at AFM? I remember last time when idle suck during aircon on, the foreman re-wired aircon vsv (maybe the vsv did not switch on). After wiring done the idle still suck the he adjust the screw at afm. SO what actually the screw use for? Some said do not touch the screw.

---------- Post added at 11:49 AM ---------- 6 hour anti-bump limit - Previous post was at 11:38 AM ----------

What is function of the screw at AFM? I remember last time when idle suck during aircon on, the foreman re-wired aircon vsv (maybe the vsv did not switch on). After wiring done the idle still suck the he adjust the screw at afm. SO what actually the screw use for? Some said do not touch the screw.

 

[feipepe]

hi to everyone bro,
i'm newbie for this forum, need u all to help, because my levin bzr spoiler brake lamp suddenly malfunction. shall u all having this issue before? besides that, now i also facing shortage about the wire socket for the crystal white sides corner and also the wire socket for the small lamp.may i know where i can buy these item?(wire socket, and brake lamp levin BZR)

 

[LevinTE27]

What is function of the screw at AFM? I remember last time when idle suck during aircon on, the foreman re-wired aircon vsv (maybe the vsv did not switch on). After wiring done the idle still suck the he adjust the screw at afm. SO what actually the screw use for? Some said do not touch the screw.

---------- Post added at 11:49 AM ---------- 6 hour anti-bump limit - Previous post was at 11:38 AM ----------

What is function of the screw at AFM? I remember last time when idle suck during aircon on, the foreman re-wired aircon vsv (maybe the vsv did not switch on). After wiring done the idle still suck the he adjust the screw at afm. SO what actually the screw use for? Some said do not touch the screw.

The screw on top of AFM is the bypass valve from afm flapper ... it would help to slightly adjust the idle fuel mixture

 

[levin818]

Yes, it is for emission (CO) adjustment only. NOT for idling rpm adjustment.

 

[me2kimi]

So it is for air fuel ratio tune right?

 

[levin818]

It decides how much air bypass the AFM flap before go into the engine (not read by the ECU) so will have some effect on the A/F if you adjust it.
Some sifu here have tried to mess with it but ended up no significant result.
Any how it is for emission (CO) adjustment only NOT for other purpose.

 

[me2kimi]

Bro Levin818, by using checking O2 sensor method I guess I've manage to adjust air fuel mixture better from before by turning that screw.
Initial status is O2 reading are always 0.9 volt which is rich right, then turning the screw counterclockwise until the O2 reading fluctuated between 0.2 to 0.9 volt. I've also made DIY AFR gauge to check it.

 

[levin818]

I didn't try it out in your way before, and it sounds interesting.
Please feedback your experience and result. It is very much appreciated.

 

[me2kimi]

I'll post a video later.

 

[me2kimi]

Here come the video. At first the voltage is constant at 0.8 volt which is rich.
So I turn to counterclockwise and notice the voltage start fluctuated.YouTube - 4AGE Silvertop adjust air fuel