Engine Help!! Code 56 new maf!

[Hunterlanigan]

I need some help! I’m working on my 90 gt, when I start it up it’ll lope and run really rich, there’s usually a good amount of black smoke. So I dumped the codes and the only two I get are 81 and 56. And I’ve been told not to worry about the 81. I don’t know why I’m getting a code 56 though? I have a brand new maf and pigtail. Could anyone give me some help?

Thanks

 

[General karthief]

Any modifications?

 

[Hunterlanigan]

Stock other than cold air intake. Other the last week the I’ve fixed a bunch of issues replaced thermostat, colant temp sensor, air charge temp sensor, plugs, alternator, battery. This is the only thing I just can’t figure out and to be honest I’m getting fed up with this thing..

 

[General karthief]

Help me create the "Surging Idle Checklist"

Updated 26-Oct-2019 to clarify creeping idle RPM increase as the car is being driven. Many of you are familiar with the "Cranks OK, but No Start Checklist for Fuel Injected Mustangs" checklist and the No Crank Checklist. They are very effective in finding and eliminating the problems by use of...

forums.stangnet.com

Do the list, be patient, take notes, ask questions here if needed.

 

[Hunterlanigan]

I’m thinking it’s something to do with the maf since I got the code 56, but what should I test? The sensor it’s self is brand new

 

[General karthief]

Look through the list, it should tell you about the test procedure.

 

[Mustang5L5]

Is it a stock replacement MAF? Brand new? What’s the part number on the MAF electronics?

code 56 is “MAF VOLTAGE TOO HIGH”. This could be due to the wrong MAF so step one is to verify its correct for your car

 

[Hunterlanigan]

Ok thank you for that link I’ll go through it today. It’s supposed to be a stock replacement, it’s brand new from the parts store

 

[Hunterlanigan]

Update: now when I turn the key on there’s a loud buzzing noise coming from the passenger side kick panel. Bad computer?

 

[Mustang5L5]

There is an ECU relay in there. You’ll want to see if that is what is buzzing.

 

[Anewjer00]

So any conclusions here ? FIXXED ?