Just installed wideband. High idle/cruise AFR?

[JStyles]

So I just installed a speedhut gauge with an AEM wideband and at idle, the AFR is all over the place. It ranges from 15-16.5 while idling and flutters within the same range while cruising.

Under WOT, it instantly goes to 11.9-12 and stays there until I let off so I know it's working. FWIW, the 02 bung is also welded before the cat on the driver side of the midpipe.

I've searched, and the only potential cause I can think of is a vacuum leak. Anyone have any suggestions on possible causes? Is it dangerous to have the car idling/cruising? I'm at least happy to see a good AFR at WOT...

Edit: videos added

[nomedia="http://www.youtube.com/watch?v=BCqpJzrfTT8"]August 22, 2011 9:24 PM - YouTube[/nomedia]
[nomedia="http://www.youtube.com/watch?v=jy7HATlt8d0"]August 22, 2011 9:16 PM - YouTube[/nomedia]

 

[03cobra#694]

Should be around 14.7, but they will jump around a bit. What does your car idle at, rpm wise?

 

[01Jes]

I agree with the above post. Mine runs a fat tune and needs to lean out abit. Although @ idle it 14.2-15.2, during WOT it sits @ 10.9 too rich.

 

[JStyles]

Should be around 14.7, but they will jump around a bit. What does your car idle at, rpm wise?

Well mine never dips below 15 except under WOT where is goes to the aforementioned steady 12. Off the top of my head I think it idles around 850, ill have to check today. I do know that while idling there's no surging. It stays right at that rpm.

 

[JStyles]

Correction, I drove it today and it idles steady at 950 rpm...

 

[Black Cobra]

Are you running E10 fuel?

 

[Bdubbs]

During idle and cruising mine is in the 14.2-14.8 range. Although last summer at wot mine was a consistant 11.7, now it's at 11.1, not sure why but better a little rich than lean. I just checked my plugs yesterday and they all looked good.

OP I had a aem wideband last year and I never got it to work right, think my sensor was bad, did you buy it new?

 

[JStyles]

Are you running E10 fuel?

Yep, what would that cause?

OP I had a aem wideband last year and I never got it to work right, think my sensor was bad, did you buy it new?

Yeah, bought it brand new. The fact that it jumps right down to 11.9 - 12 at WOT makes me think it's working correctly...:shrug:

 

[Black Cobra]

Depending on whose number you use E10 has a stoich value of 14.1 to 14.2 which is 0.5 to 0.6 less than regular gas. The stock tune is setup for regular gas which is 14.7. So E10 causes the engine to run 0.5-0.6 leaner than regular gas. So I would say this accounts for some of it.

Edit: You're probably making more power in WOT with the E10...

 

[JStyles]

Depending on whose number you use E10 has a stoich value of 14.1 to 14.2 which is 0.5 to 0.6 less than regular gas. The stock tune is setup for regular gas which is 14.7. So E10 causes the engine to run 0.5-0.6 leaner than regular gas. So I would say this accounts for some of it.

Edit: You're probably making more power in WOT with the E10...

Hmm makes sense. Would this still be the case even though the car was dyno-tuned using E10?

Thanks for the replies guys!

 

[JStyles]

Here are two vids as well - one idling/revving and one quick WOT punch...

[nomedia="http://www.youtube.com/watch?v=BCqpJzrfTT8"]August 22, 2011 9:24 PM - YouTube[/nomedia]

[nomedia="http://www.youtube.com/watch?v=jy7HATlt8d0"]August 22, 2011 9:16 PM - YouTube[/nomedia]

Anyone else have an idea of the high air/fuel? Thanks in advance!

 

[Black Cobra]

Anyone else have an idea of the high air/fuel? Thanks in advance!

What were the calibration procedures that you had to do for the speedhut gauge and AEM sensor?

 

[JStyles]

What were the calibration procedures that you had to do for the speedhut gauge and AEM sensor?

Per AEM instructions, no calibration needed.

 

[10thSVT_03]

I have had the AEM uego in my last 5 stangs and I have only had one sensor fail on me.

 

[03cobra#694]

Hey, I just noticed you're using a SH gauge. Did you set the gauge for the AEM? I'm pretty sure the gauge comes set for a Innovative w/b and you have to change settings for your type of w/b.

 

[JStyles]

Well I ordered the one for the aem. Maybe they sent the wrong one? I'll check with them to see.

 

[03cobra#694]

Well I ordered the one for the ask. Maybe they sent the wrong one? I'll check with them to see.

OK, I just went to their site and saw that you can order the gauges for specific w/b's. That must be new, they used to only have the one a/f gauge that you had to program to your w/b.

 

[JStyles]

OK, I just went to their site and saw that you can order the gauges for specific w/b's. That must be new, they used to only have the one a/f gauge that you had to program to your w/b.

So I talked to Speedhut today and they told me they sent a Dynojet compatible gauge by mistake. They're going to make a correct one for me and send return shipping as well for the incorrect gauge.

It sucks that I'll have to wait for the new one, but I applaud them for their great customer service. I would recommend them to anyone looking for custom gauges.

Thanks for all the input/replies guys! I'll update when I get the new one in.