MAF Question

[jreyn]

I know this is unbelievably rookie, but I have to ask. I just purchased an HP EFI system for my currently MAF '90 Fox body Mustang. I’ve been reading through everything I can, and haven’t really figured out what you do with the MAF sensor that’s in the car now? Since I’m installing a MAP sensor, does the MAF sensor get removed or will I leave it in the cold air just unplugged? Thanks in advance!!!

[Danny Cabral]

Yes, remove the MAF sensor. Holley EFI is a Speed Density EFI system only (MAP sensor).

[S2H]

If it's easier to leave it in place, that is fine. It will just be there physically because it's part of your intake tubing.
It just won't have anything plugged into it, as the Holley comes with a stand-alone IAT/MAT sensor for you to use.

[Danny Cabral]

I thought of that too, but he asked if he should remove it, so it seems like an option for him. Personally, I'd hate to leave a non-functioning MAF sensor installed.
https://lmr.com/item/BBK-1558/1986-8...r-Non-Mass-Air (BBK Adapter for Speed Density EFI)

[jreyn]

OK, thank you. For now I'll leave the MAF until I get it all setup & running. I need to ask one more question. Reading through the Ford IAC wiring thread is a little confusing to me. For confirmation. I want to use the Holley 550-606 HP EFI ECU & Harness Kit with its Chrysler style connector for the IAC. So I need to order Standard Motor Products AC416 IAC motor and the adapter installation plate for my throttle body. This will be a direct plug & play for my '90 5.0L Fox body? Thanks again, I think this is the last thing I need to make sure I understand!

[Danny Cabral]

I want to use the Holley 550-606 HP EFI ECU & Harness Kit with its Chrysler style connector for the IAC.

Yes, that's wired for the Chrysler IAC motor.

So I need to order Standard Motor Products AC416 IAC motor and the adapter installation plate for my throttle body.

Yes, if you're converting it to the 4-wire stepper type IAC motor.

This will be a direct plug & play for my '90 5.0L Fox body?

I don't understand what the "plug & play" IAC motor has to do with your '90 5.0L Fox body?

[jreyn]

I just mean if I purchase that IAC and install it on the adapter plate, all I do is plug in the Holley EFI harness and move on with the rest of the installation? That's all I need to order to finish that job?

[Danny Cabral]

Yes, the Chrysler 4-wire stepper IAC motor is "plug & play" into the Holley EFI main harness. In other words, that's what it's wired for.

[jreyn]

Danny, thank you for your help! I'm probably 3/4 through the installation on the car and now starting to build my EFI software (Global File). I have a question on the ignition that I can't understand through the Help files.
I'm running a TFI ignition, the factory Ford setup. However, I'm also running the MSD 6AL CD box. Will I be selecting Ford TFI or CD Box Tach Output under Ignition Type? They both fit the description of options to use?

[Danny Cabral]

I'm running a TFI ignition, the factory Ford setup. However, I'm also running the MSD 6AL CD box. Will I be selecting Ford TFI or CD Box Tach Output under Ignition Type?

Select "Ford TFI 8 Cylinder (SEFI)", with or without a CD ignition box.
http://documents.holley.com/techlibr...10555rev17.pdf (Holley EFI Wiring Manual - Figure 5 & 6, Page 14 & 15)

They both fit the description of options to use?

No, the "CD Box Tach Output or any 12V Square Wave (No Timing Control)" is a non-ECU timing control application.

[jreyn]

I ordered the AC416 Idle air motor, I also ordered the Accufab GM adapter. I go to assemble them and the holes in the GM to Ford Accufab adapter do not line up with the motor mounting holes. I called Accufab and they do not make a adapter to fit the Chrysler idle air motor to the GM plate? Can I just elongate the hole on idle air motor to make the screws fit? Or do I have to go back and order a GM specific motor and then repin the Holley harness?

[Danny Cabral]

I called Accufab and they do not make a adapter to fit the Chrysler idle air motor to the GM plate? Can I just elongate the hole on idle air motor to make the screws fit?

I'd try that first (if it's only a little elongation).

[ToysRs]

I ordered the AC416 Idle air motor, I also ordered the Accufab GM adapter. I go to assemble them and the holes in the GM to Ford Accufab adapter do not line up with the motor mounting holes. I called Accufab and they do not make a adapter to fit the Chrysler idle air motor to the GM plate? Can I just elongate the hole on idle air motor to make the screws fit? Or do I have to go back and order a GM specific motor and then repin the Holley harness?

I ran into the same issue, and just took my Dremel and used a very fine-tip cutter and carefully elongated only the edge of the hole needed to get the screw in. What I mean by that, is I did not enlarge the entire hole, only the edge closest to the screw hole on the Accufab adapter. I only altered the hole as little as I needed to. I also made sure to clean any tiny metal shavings away from the assembly before installing the motor into the adapter. This secured the IAC securely to the adapter. As far as asking questions, don't be afraid to ask about anything that you aren't sure about.

[jreyn]

Danny, I have another quick question. I finished wiring the system with the Digital Dash. ECU firmware updated and seems to be responding, but I have not yet had time to go through the TPS sweeps. With the key in run position and the EFI software linked, should my Digital Dash be powering up, or will that not happen until I actually start the car? Basically key-on/engine-off, the Digital Dash is not powering, and the manual doesn't say exactly when it should come on? Thanks again

[Danny Cabral]

Yes, key-on/engine-off, the Digital Dash should be powered on. Ensure the Digital Dash +12V white wire is powered in the "Run" and "Crank" key positions.
http://documents.holley.com/199r10746rev1.pdf (Holley 553-106 Digital Dash Instruction Manual)