1fzfe turbo Air Fuel Ratios

[Fj80oregon]

been working on getting my turbo buttoned up and finally got it fired up. I’m using a HD automotive j pipe and pulsar turbo. Have a AEM boost , water, and AFR gauge my question is what causes it to read lean. At idle I’m at 14.7ish but when I accelerate in drive(have not installed drivelines yet or driven) I get up in the 15/16s and shut it off. I have a new fuel pump installed with premium fuel I know that fuel grade doesn’t affect AFR. I have tested for vacuum leaks and everything is solid. This is a freshly rebuilt engine bored over .50mm and all new internals. Timing is set at 3. Looking for some input to bring the air fuel ratio down so I can go break this thing in. Thanks in advance.

 

[Fj80oregon]

That first picture is 14.55 on the AFR gauge.

 

[Fj80oregon]

Better pictures at idle. I wonder if the ECM still needs to learn what the hell is going on with a new motor.

 

[OffRoadScott]

You might want to consider installing a fuel pressure riser that adjusts based off vacuum.

 

[ThreeEyedBandit]

Go for a drive, without any load on the engine you will not get any useful information or allow the ecu to learn closed loop values. It will take a bunch bad noise and heat before you melt it down.

Also make sure this is plugged.

 

[Fj80oregon]

Go for a drive, without any load on the engine you will not get any useful information or allow the ecu to learn closed loop values. It will take a bunch bad noise and heat before you melt it down.

Also make sure this is plugged.
View attachment 3613269

Sounds good that is plugged with a cap just shoved in there until the right size comes in the mail.

 

[Fj80oregon]

Rehashing this, engine is running great and finally putting some miles on this build. AFR readings at idle 14.4-15.2 continues bouncing around in that range. Normal City driving not under boost low 14’s. Under boost 13-14.5. Under WOT 12.7-13.5 these are the numbers I’m seeing after about 150 miles. Does any of this raise red flags? Thanks Wes

 

[White Stripe]

Rehashing this, engine is running great and finally putting some miles on this build. AFR readings at idle 14.4-15.2 continues bouncing around in that range. Normal City driving not under boost low 14’s. Under boost 13-14.5. Under WOT 12.7-13.5 these are the numbers I’m seeing after about 150 miles. Does any of this raise red flags? Thanks Wes

That's too lean. What is your fuel pressure regulator vacuum line plumbed to?

 

[ChargedSHOTaco]

That's too lean. What is your fuel pressure regulator vacuum line plumbed to?

Looks like it is plumbed correctly, connected to a vac line at the throttle body.
Prior to installing a standalone, my stock ECU would push the AFR to 10.0 at WOT.

 

[Fj80oregon]

That's too lean. What is your fuel pressure regulator vacuum line plumbed to?

Stock configuration, new OEM regulator, new Supra fuel pump, new filter all installed when the engine was rebuilt.

 

[Fj80oregon]

Looks like it is plumbed correctly, connected to a vac line at the throttle body.
Prior to installing a standalone, my stock ECU would push the AFR to 10.0 at WOT.

Yah trying to get the AFR down to something close to that. This is a first for me never had a boosted engine and trying to get it right. Any suggestions?

 

[ChargedSHOTaco]

Yah trying to get the AFR down to something close to that. This is a first for me never had a boosted engine and trying to get it right. Any suggestions?

If you have triple checked for vacuum and exhaust leaks, and recalibrated the sensor and you continue to get high AFRs, I'd consider getting a new wideband sensor to double check. I've seen a few friends have issues with those sensors (dying after 3 weeks, extremely high AFRs, etc).

 

[lumbee1]

I'm supercharged and just installed my AEM. I plan on installing this to help with lean conditions under boost.

LSC2-001 Universal Fuel Enrichment Module |

splitsec.com

 

[Fj80oregon]

I'm supercharged and just installed my AEM. I plan on installing this to help with lean conditions under boost.

LSC2-001 Universal Fuel Enrichment Module |

splitsec.com

The stock ECM should be able to handle a 5-8 psi set up but I like the idea of some insurance. Might go with a meth injection system after I get this dialed.

 

[Fj80oregon]

If you have triple checked for vacuum and exhaust leaks, and recalibrated the sensor and you continue to get high AFRs, I'd consider getting a new wideband sensor to double check. I've seen a few friends have issues with those sensors (dying after 3 weeks, extremely high AFRs, etc).

Going to check vacuum leaks today with a smoke machine and I do know I have a slight exhaust leak at the catalytic converter, was not aware that would affect the afr. Will get that sorted as well.

 

[Rwhat]

Any updates? Finally got mine running last week. Only took 18 months. Still need to install my gauges.