rough idle

[william spear]

I have a rebuilt engine with greddy s 50 trim 680 injectors the safc is set at zero across the board. The other day code po505 comes cleared code car idles like crap. checked the iac 30 ohms ok.After the cel it smokes at idle and sounds like it is muffy at the tail pipe what else could be.

 

[GVR4592]

680 injectors the safc is set at zero across the board

Hmmmm.......rich you say?

 

[william spear]

I have the safc zeroed out and the boost set at 10 till i break in the engine. At first i had a coolent leak under the throttle body fixed it then tried to adjust the bov reved it to 35000 rpms car ran smother then it ever did then i got the cel. When i turn the ac on the rpms drop to 400 and sounds like it is going to stall. I it the iac motor.

 

[william spear]

Help guys i took out the iac cleaned it hooked it up out of the tb and it moves in and out very little not really sure how far it is sopose to move. I also found a vacuum hose off the egr and put it on. When i started the car it idled smooth the af gauge went to rich till the car warmed up then it idled like crap again. Iam going to let the car sit over night and see how it idles in the am. If it dose the same thing can it still be a bad iac or egr valve. All sensors are original 160000 miles.

 

[paul s]

Why do you have the afc set to 0..?????. You do have bigger injectors so you have to compensate for it...

 

[william spear]

The motor is still not broke in yet only have 250 miles on it .I have 680 injectors 50 trim 268 cams je pistons scat rods greddy s fmic. The engine was installed at extreme they set the safc to zero till it get broken in and tuned. Car ran fair till the cel came on po505 then idled rough.

 

[william spear]

Cleaned the iac yesterday car started and idled fine till it warmed up then idled poor started it up in the am warmed it up and it idled fine. Took it out for a drive the car ran great no idle problem at all maybe cleaning the iac helped. May be the iac is starting to go soon.

 

[GVR4592]

The safc setting is the problem. You have 680's, stock is 450's. That's 30% larger than stock. That's a significant increase in fueling. You need to compensate for that. Running your engine that rich can cause damage.

 

[william spear]

I have my idle problem ok sill smokes at idle gray looking smoke plugs look like new. Hooked up my palm at idle 10 degrees of timing 900 rpm. Yesterday i orded a 95 eprom ecu with a stage 3 chip. Do you think the smoke is a rich condtion car runs great.

 

[Mist3r Spool]

Lean out your idle a bit (on SAFC). I have mine at -14 and I have RC 550s...

 

[Mr.Tao]

All the clues your giving leads to car being rich. But you keep saying that you need to break in your engine? Your using larger injectors with stock settings. How is it supposed to run? Try leaning it out and see how it idles. It's not like your gonna be stomping on your engine are you?