I need help

[ShadowBolt]

I am still having trouble with my race car.
I need a stock Motorcraft MAF sensor
Part number
F6UZ-12B579-YRM

They are $315.00 for a rebuilt one and I can't find a new one at all.


Jerry

[Sook]

Just did some googling, holy smokes those are expensive!

My S197 has 'run with failed MAF' tables. If you unplug the MAF does it run OK? Looks like Rockauto has a dephi sensor only for $100. https://www.rockauto.com/en/catalog/...ow+sensor,5128

A SBF 302 is legal for your car.

- Josh

[ShadowBolt]

Just did some googling, holy smokes those are expensive!

My S197 has 'run with failed MAF' tables. If you unplug the MAF does it run OK? Looks like Rockauto has a dephi sensor only for $100. https://www.rockauto.com/en/catalog/...ow+sensor,5128

A SBF 302 is legal for your car.

- Josh

I was told by a dyno guy that is trying to help me that there are lots of issues with aftermarket MAF's. I just bought what someone said was NOS off e-bay for $35.00 but we will see what I really get. I may go to a junk yard and get one. I have used two different MAF's on my last two dyno sessions (both aftermarket)and gone from 202/219 and 11:1 a/f to 212/265 and 15.3 a/f. I also went from a cut up CAI to an Airaid unit that is made very well. The dyno guy told me the car was going to 1.0 lambda at WOT in the 15.3: session. Whatever the hell that means. The car threw the code P0358 (number eight coil not firing and the guy said that could have caused the car to go into the 1.0 lambda crap. I'm sick of this shit! I have no idea where the Motorcraft MAF went as we changed it at Cresson last year chasing running rich issues that it looks like I got after cutting the CAI up to make everyone happy that I was not running ram air with a filter in the fender well. Most likely that cost me the engine through fuel wash.
At the end of the day I'm not sure this is all worth it. I would be happy to go back to carbs and points and rotors and one coil.
Jerry

[Supercharged111]

Jerry you should have been able to hole saw a hole between the engine bay and fender area to create a compliant bleed. I'd rock a junkyard sensor before scouring the ends of the Earth for new OEM.

[Sook]

Lambda is the ratio of the engine's current AFR to the ideal stoichiometric AFR (14.7 for gasoline). Tuners use it because it doesn't vary with fuel (diesel, E85, etc.) - you'll always know what 1.0 lambda means. Less than 1.0 is rich, greater than 1.0 is lean.

15.3/14.7 = Lambda of 1.04

[Supercharged111]

Lambda is the ratio of the engine's current AFR to the ideal stoichiometric AFR (14.7 for gasoline). Tuners use it because it doesn't vary with fuel (diesel, E85, etc.) - you'll always know what 1.0 lambda means. Less than 1.0 is rich, greater than 1.0 is lean.

15.3/14.7 = Lambda of 1.04

To piggyback on this, E10 stoich is 14.3:1. All O2 sensors read in lambda, the readout to the end user is typically in AFR. If your wideband is configured to read AFR based on a stoich ratio of 14.7:1 and you're running E10, the AFR readings will be inaccurate. Because it's based on lambda, however, if your E0 target was 13:1 and on E10 your gauge reads 13:1, you're still at the same lambda and therefore damn close to where you want to be. Only difference would be the delta in the motor's lambda preference between E0 and E10 assuming there was one.