installed wideband & AFPR, idle is very LEAN!!!

thevork

thevork

ShoarmaTeam Member
Apr 28, 2005
657
0
16
Vroomshoop, Netherlands
www.shoarmateam.nl
tbcmorris;1224997 said:
do you have anything to back this up? i was taught that idle is not one of the parameters that needs to be met in order to operate in closed loop. i was taught that it was more dependent on engine temp than anything. leading me to believe that there would be 2 different idle programs. one to satisfy cold startup idle(closed) and warm idle (open)my car idles at about 14.7 open or closed loop. my problems comes in on my WOT AFR where i dip below 10 :(
Click to expand...


well cold startup is indeed open loop. everything after that is closed loop until some percentage close to the 70% mentioned above.

jetjock on here told me a while back when i was having problems with my a/f also.

@mk3tattoos
You really don't need an aftermarket standalone ecu. maybe a fuel computer to keep your fuel economy down a bit.
My car is running a perfect 14.7 idle with 550/lexafm, an aftermarket afpr and safc. All mods to support the bigger turbo.
 
grimreaper

grimreaper

New Member
Jul 2, 2008
2,180
0
0
Dallas
set your fuel pressure per the tsrm. only time you should be changing it is to roughly adjust wot af ratios's. keep the fuel pressue in the middle of the range spec'd by the tsrm if you can.

something i ran into: the rc's hit a limit at 22psi with vac on. Lean idle, and lean low load cruising. Bumped it back up to 25psi vac on and everything is perfect.
 
mk3tattoos

mk3tattoos

New Member
Apr 12, 2008
1,104
0
0
Bremerton, Wa
grimreaper;1225640 said:
set your fuel pressure per the tsrm. only time you should be changing it is to roughly adjust wot af ratios's. keep the fuel pressue in the middle of the range spec'd by the tsrm if you can.

something i ran into: the rc's hit a limit at 22psi with vac on. Lean idle, and lean low load cruising. Bumped it back up to 25psi vac on and everything is perfect.
Click to expand...
So set me pressure to 25 with vac line on? I put the 02 sensor on and the A/F stays at 14.5 all the time unless i wot. then it goes to 10. but after cruising for 20 min. i pop the hood and manifold is alittle red. is this OK?
 
C

cjsupra90

previously chris90na-t
Jun 11, 2005
1,029
0
0
48
Lakeland, FL
If your manifold is getting that hot while cruising, your timing is most likely off... A lot of people dont seem to understand that when everything is set correctly, 14.7:1 AFR will give the highest EGT's leaner or richer then this will lower the EGT's if the timing is correct. This has been proven time and time again and I have proved it to people in my car when it was a 7m turbo and had an EGT monitor through the datalogger...

One other question as this get a lot of people confused... When its showing that its idleing at 16:1, is it idleing smooth or rough? If rough then lean try leaning it out some and see if it smooths out and the AFR's start to drop... This might seem backwards, but another think a lot of people dont understand is that rough running and misfires inparticular will show lean on the gauge cause there is excess unburn oxygen in the exh. and thats actually what the sensor is reading.. I just delt with this on a car I was tuning for someone who tried to tune it themselves not to long ago.. He noticed that under heavy power load that the engine was breaking up and the WB was showing pretty lean so he add fuel and it only got worse and showed even leaner.. This was all because he had to much fuel to begin with and it was misfiring...
 
C

cjsupra90

previously chris90na-t
Jun 11, 2005
1,029
0
0
48
Lakeland, FL
Oh and I have heard countless times people say that they or someone wired something up perfect and and yet is was far from perfect to say the least...

Did you'll do a flatline votage test on the output to the ECU to make sure the voltage at the ECU was correct?
 
grimreaper

grimreaper

New Member
Jul 2, 2008
2,180
0
0
Dallas
cjsupra90;1225672 said:
If your manifold is getting that hot while cruising, your timing is most likely off... A lot of people dont seem to understand that when everything is set correctly, 14.7:1 AFR will give the highest EGT's leaner or richer then this will lower the EGT's if the timing is correct. This has been proven time and time again and I have proved it to people in my car when it was a 7m turbo and had an EGT monitor through the datalogger...

One other question as this get a lot of people confused... When its showing that its idleing at 16:1, is it idleing smooth or rough? If rough then lean try leaning it out some and see if it smooths out and the AFR's start to drop... This might seem backwards, but another think a lot of people dont understand is that rough running and misfires inparticular will show lean on the gauge cause there is excess unburn oxygen in the exh. and thats actually what the sensor is reading.. I just delt with this on a car I was tuning for someone who tried to tune it themselves not to long ago.. He noticed that under heavy power load that the engine was breaking up and the WB was showing pretty lean so he add fuel and it only got worse and showed even leaner.. This was all because he had to much fuel to begin with and it was misfiring...
Click to expand...

good stuff!
 
mk3tattoos

mk3tattoos

New Member
Apr 12, 2008
1,104
0
0
Bremerton, Wa
cjsupra90;1225674 said:
Oh and I have heard countless times people say that they or someone wired something up perfect and and yet is was far from perfect to say the least...

Did you'll do a flatline votage test on the output to the ECU to make sure the voltage at the ECU was correct?
Click to expand...

i will try that, thank you for the great info. I dont believe we checked the voltage on the output of the ECU, so thats something that need to be done.

what should are timing be sset at? I've heard diffrent things.
 
mk3tattoos

mk3tattoos

New Member
Apr 12, 2008
1,104
0
0
Bremerton, Wa
[

One other question as this get a lot of people confused... When its showing that its idleing at 16:1, is it idleing smooth or rough?

yea when it's at even 15.0 to 16.5 it is rough and loping. but if it idles at 13.5 it is alot smoother. i will try and lean it out and take away some fuel and see if that helps until i get a tuning device.

thanks
 
mk3tattoos

mk3tattoos

New Member
Apr 12, 2008
1,104
0
0
Bremerton, Wa
thevork;1227043 said:
did you check and fix your vacuum leaks yet?
Also, did you recently replace the timing belt? It can be one tooth off or maybe two?
Click to expand...

yea i fixxed the vacuum leak, and i replaced the timing belt with the blue greddy one when we did the rebuild last year.
 
thevork

thevork

ShoarmaTeam Member
Apr 28, 2005
657
0
16
Vroomshoop, Netherlands
www.shoarmateam.nl
So for all you know it may have never been perfect since the rebuild ?

If all your vacuum leaks are gone, and you can't get it exactly right i'd check the timing belt first. It happens too many times that it shifts a tooth on one of the cam wheels right after installation. Seen it multiple times myself.
 
mk3tattoos

mk3tattoos

New Member
Apr 12, 2008
1,104
0
0
Bremerton, Wa
thevork;1228779 said:
So for all you know it may have never been perfect since the rebuild ?

If all your vacuum leaks are gone, and you can't get it exactly right i'd check the timing belt first. It happens too many times that it shifts a tooth on one of the cam wheels right after installation. Seen it multiple times myself.
Click to expand...

so to check to see if it did what would i do? I checked the timing gears and they are lined up, and the timing is set to 10 degrees. I'm i missing something?
 
Last edited:
thevork

thevork

ShoarmaTeam Member
Apr 28, 2005
657
0
16
Vroomshoop, Netherlands
www.shoarmateam.nl
Okay and at what value did you say you set your fuel pressure at?
it needs to be at least 32psi with the vacuum hose off. That's what the tsrm says if I'm not mistaking.

I believe I set it to about 38psi on my car.
What value is your Vf @ warm idle ?
 
You must log in or register to reply here.
Top Bottom