How do I read the AFR on a 2007 mustang GT?

[Fenceingmadman]

I have a Snap on solus pro obd-2 reader, I can read the voltages on the o2 sensors but not the AFR. this is weird because on all of my similar year chevys I can easily read them in the live data area.

Also is it normal to have a 172⁰ IAT reading at idle and a 130⁰ at 70 mph? Would cleaning the MAF make it run better? It was only 95⁰ outside the car.

I'm getting 11 MPG and am down on power once warmed up. Starting to think its a MAF or O2 issue.

 

[Dino Dino Bambino]

You'll need a wideband O2 sensor with gauge to get accurate AFR readings, but you can still find out if your engine's running rich by looking at your B1S1/B2S1 O2 sensor readings and your short/long term fuel trims. Post your results so we can analyze them.

Your IATs are way too high and appear to be the same as what I'd expect your underhood temperatures to be. Do you have an aftermarket "CAI" with a conical filter that's exposed under the hood with either no heat shield at all or a crappy heatshield that's as useful as tits on a bull? If so, perhaps my modified JLT 3 CAI will inspire you.

 

[Juice]

If you are concerned with MPG, your title is misleading.
In closed loop, afr should be 14.1 based on everything is cal'd for e10. No wideband needed here.
Both upstream O2 sensor should be actively switching rich/lean.
Adaptive corrsctions should be close to zero on both LT and STFT.
Since you said nothing about codes or a check engine light, could it be clogging catalytic converters?

WOT aft is another topic.

 

[GlassTop09]

Also is it normal to have a 172⁰ IAT reading at idle and a 130⁰ at 70 mph? Would cleaning the MAF make it run better? It was only 95⁰ outside the car.

Hi Fenceingmadman,
If these IAT readings you've posted are true, then this is an issue as these are too high so the ECU is pulling spark timing out to compensate for this so this will have an adverse effect on the MPG & engine power output (typical SO OEM calibration has the IAT correction upper deadband limit (the upper running IAT allowed to exist w\o any spark timing correction applied) is 110*F so any running IAT above this threshold will cause the ECU to start retarding spark timing to avoid detonation. So yes, you should start out by pulling the MAF sensor & inspecting the hot wires for debris buildup\obstructions & clean it out then reinstall it to see if this corrects.
When sitting at idle & 0 MPH, it is usual for the running IAT to be higher than it would be when at speed (sitting still, there is no ram air flow to "seal" the under hood heated air coming off engine\exhaust manifolds\radiator fan away from the CAI inlet\MAF sensor) but even then, the IAT should not be getting higher than around 140*F max at those ambient temps of 95*F when sitting still & should also be below the 110*F threshold when moving (if under hood components are still OEM....especially the exhaust manifolds.....and engine hasn't been tuned to increase HP\TQ above OEM outputs).

If cleaning the MAF doesn't resolve this issue, then you might need some diagnostics run to determine if the MAF sensor is failing to warrant replacement (these MAF sensors aren't cheap & you'll want to go w\ a Ford MC AFM-131 OEM replacement MAF........can go aftermarket as well but these are a crap shoot in accuracy\reliability.....) because a loose\corroded terminal connection in MAF connector may also be a culprit if cleaning the MAF doesn't fix it. I would suggest to also get some dielectric grease & apply it to the MAF connector terminals\pins to help arrest any semblance of terminal oxidation\corrosion formation in future.

Otherwise, what the others have already posted.

Hope this helps.

 

[Juice]

In the last pic, I can see the ABS module. So the cold air intake is sucking hot air from the engine bay.
Those temps are not out of the relm of possible, based on that photo.
Please dont tell us you have a Bama tune on there.

 

[Dino Dino Bambino]

In the last pic, I can see the ABS module. So the cold air intake is sucking hot air from the engine bay.
Those temps are not out of the realm of possible, based on that photo.
Please don't tell us you have a Bama tune on there.

I think you're getting confused. Those photos are mine, not the OP's. I have a Brenspeed tune and at any speed over 40mph, my IATS are barely above ambient. I've completely sealed off my air filter from the engine compartment and it takes a few minutes of idling time to get the IAT up to 110*F. Once on the move again, it quickly comes down.

 

[AHaze]

Those IATs have to be wrong unless it was 120°+ outside. I have Vortech's standard air intake which is basically an open cone filter with a small shield to protect it from radiant heat. It definitely still pulls in under hood air when stopped but I've never seen an IAT over 130°F which would have been about 40° above ambient. If the car is moving much more than 15 mph, IATs drop back to within 10° of ambient.

 

[Fenceingmadman]

You'll need a wideband O2 sensor with gauge to get accurate AFR readings, but you can still find out if your engine's running rich by looking at your B1S1/B2S1 O2 sensor readings and your short/long term fuel trims. Post your results so we can analyze them.

Your IATs are way too high and appear to be the same as what I'd expect your underhood temperatures to be. Do you have an aftermarket "CAI" with a conical filter that's exposed under the hood with either no heat shield at all or a crappy heatshield that's as useful as tits on a bull? If so, perhaps my modified JLT 3 CAI will inspire you.

View attachment 89340 View attachment 89341 View attachment 89342

The entire car is stock as far as I can tell besides this awfully installed stereo, Ill check the B1S1 and B2S1 readings real quick and report back

 

[Fenceingmadman]

You'll need a wideband O2 sensor with gauge to get accurate AFR readings, but you can still find out if your engine's running rich by looking at your B1S1/B2S1 O2 sensor readings and your short/long term fuel trims. Post your results so we can analyze them.

Your IATs are way too high and appear to be the same as what I'd expect your underhood temperatures to be. Do you have an aftermarket "CAI" with a conical filter that's exposed under the hood with either no heat shield at all or a crappy heatshield that's as useful as tits on a bull? If so, perhaps my modified JLT 3 CAI will inspire you.

View attachment 89340 View attachment 89341 View attachment 89342

Alright I reread all readings. IATS are still bad, it's about 97⁰ and it read 130 at 60 mph and climbed to 150 at stoplights.

B1S1 was all over the place at idle, it dropped as low as 0.05 and usually showed 0.14. Sometimes it would read 0.86 which was close to the other 02 sensor, it showed 0.88 at full throttle.
B2S1 showed 0.72 at idle and was pretty steady and 0.93 at Full throttle.

 

[Dino Dino Bambino]

B1S1 was all over the place at idle, it dropped as low as 0.05 and usually showed 0.14. Sometimes it would read 0.86 which was close to the other 02 sensor, it showed 0.88 at full throttle.
B2S1 showed 0.72 at idle and was pretty steady and 0.93 at Full throttle.

It sounds like the B1S1 is fluctuating as it should from ~0.1-0.9v in closed loop idle, but the reading from B2S1 definitely sounds abnormal. I'd replace that O2 sensor. Hopefully that fixes the problem.