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Old 03-14-2008, 12:32 PM   #21
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Quote:
Originally Posted by Saml01 View Post
Could the base idle pressure on the AFPR be set wrong?

Can a car even idle at 5:1 afr?

Whats having me scratch my head is that you say it varies, from rich to lean at idle.

Any pattern? Is it correlated to something? Engine temp perhaps?
Watch the video, it's not 5:1
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Old 03-14-2008, 12:34 PM   #22
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13.1 here. Always been like that, stock injectors and 460's. Anything over 14 and its flaky.
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Old 03-14-2008, 12:36 PM   #23
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Originally Posted by DammitBeavis View Post
Watch the video, it's not 5:1
DOH...

I re read his first post. Now I see.

I cant watch the video cause im at work.:(
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Old 03-14-2008, 12:43 PM   #24
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Quote:
Originally Posted by Saml01 View Post
Could the base idle pressure on the AFPR be set wrong?

Can a car even idle at 5:1 afr?

Whats having me scratch my head is that you say it varies, from rich to lean at idle.

Any pattern? Is it correlated to something? Engine temp perhaps?
Its not 5:1. The camera catches the led's flashing on and off. The only patten I have noticed is that the car idles lower when cold and higher when warm. Opposite of what it should. The AFR's could be lean or rich. Its as if something is working intermittenmly.
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Old 03-14-2008, 12:47 PM   #25
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Here's a couple things that I do know. The intake could be leaking pre turbo, but my vacuum holds steady a 19. After turbo I highly doubt it. I have the pcv routed with a sealed catch in the line. The breater on the drivers side is hooked up with a catch venting to the atmosphere. I removed that air valve that is attached to the intake manifold right above the fuel rail (I had this problem before that). My exhaust probably is leaking before the wideband O2.
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Old 03-14-2008, 12:53 PM   #26
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Im starting to think that my best bet is ignore these problem until I get my ms so I can remove the maf and until I get my new exhaust in a couple of weeks.
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Old 03-14-2008, 01:03 PM   #27
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just a thought because i have the AEM UEGO..... AFR's can't be read below 10.... i dunno how you're getting 5's and 4's n ****
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Old 03-14-2008, 01:06 PM   #28
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just a thought because i have the AEM UEGO..... AFR's can't be read below 10.... i dunno how you're getting 5's and 4's n ****
No offence but how about reading all the posts and watching the videos before you comment.
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Old 03-14-2008, 01:29 PM   #29
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I'm going to ban the next person who mentions 4:1 or 5:1 AFR.....
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Old 03-14-2008, 01:32 PM   #30
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sorry... i was still on the first page when they were talking about 5:1 and by the time i posted you already yelled at him

MAN I DIDN"T EVEN KNOW THERE WAS A VIDEO! hahahahaha it just looked like a simple crop he made around the picture
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Old 03-14-2008, 01:36 PM   #31
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Quote:
Originally Posted by levnubhin View Post
Here are a few videos of my idle and AFR's. Please help me figure this out. I really want to get this fixed before I get my MS from Scott.

Thanks for your time.
lmao
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Old 03-14-2008, 01:37 PM   #32
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Back on subject, anyone have any other ideas?
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Old 03-14-2008, 01:56 PM   #33
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I'm going to go out on a limb and say that your wideband is lying to you. There's either a missfire, a calibration issure, or you have a leak in your exhaust and it's sucking air. I don't think it's possible to have a smooth idle running that lean. Cold start would be a bitch if it's anything near 16:1.
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Old 03-14-2008, 01:59 PM   #34
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When you unplug the IAC you idle goes down? I thought that it would jump up to about 1500rpm.

Your AFR at idle doesn't look that unusual with an AFPR. I found my old BEGI AFPR to be inconsistent as hell. Things got 100% better when I went with a Link.
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Old 03-14-2008, 02:10 PM   #35
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If the idle is raising up then I'd suggest an air leak on the intake manifold which would make it run lean and raise the idle.
When you removed the air valve, how did you cap the hole off that was left behind?

If there's a leak post AFM/MAF and before the throttle body then it would run pig rich when driving around but possibly not when idling if it can drag enough air in via the intake manifold.

Worth checking those things anyway - also stick a jumper between TEN and GND in the diagnostic connector. This will bypass the ISC control from the ECU and allow you to check the base idle properly - it should be about 850rpm without any assistance from the ECU.
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Old 03-14-2008, 02:53 PM   #36
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Quote:
Originally Posted by lwindridge View Post
If the idle is raising up then I'd suggest an air leak on the intake manifold which would make it run lean and raise the idle.
When you removed the air valve, how did you cap the hole off that was left behind?

If there's a leak post AFM/MAF and before the throttle body then it would run pig rich when driving around but possibly not when idling if it can drag enough air in via the intake manifold.

Worth checking those things anyway - also stick a jumper between TEN and GND in the diagnostic connector. This will bypass the ISC control from the ECU and allow you to check the base idle properly - it should be about 850rpm without any assistance from the ECU.

When I removed the air valve I put a metal plate with cork gasket to seal the hole. There is a good chance that there is a leak post maf before the turbo. If there is im not gonna bother with it as im waiting for my MS to come.
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Old 03-14-2008, 03:17 PM   #37
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Though it would be handy to find out if you can trust your wideband readings if you're going to be driving it. Too lean = $$$
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Old 03-14-2008, 03:25 PM   #38
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lmao
sorry levvy.... i was lookin for the video too! and i figured you were gonna post it later on in the day since they didn't look like youtube links
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Old 03-14-2008, 03:33 PM   #39
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well before I went to get some lunch I played with a couple things. I readjusted the idle at the TB and at the MAF. I test drove the car with the IAC disconnected but the idle was too high. I reconnected it and readjusted my idle. My AFR's look better but im actually very rich at WOT now 11-10. Cruise remains at 14-16 and light throttle around 13. My idle is still very lean 15.5-16. I dont really mind that because it idles fine. I just wish there wasnt so much flutcuation. Like I said earlier, once I get my MS and new exhaust, I will be able to rule out any leaks.
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Old 03-14-2008, 03:42 PM   #40
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well the stock computer is still fueling based on the NB o2....so it will sweep around....

btw, ill have your MS shipped monday. i wanted to throw it on my car this weekend before i shipped it out to make certain everything was functional.
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