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Engine Found problem but!!

  • Thread starter Thread starter Canadianfox
  • Start date Start date Apr 24, 2020
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Canadianfox

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Aug 18, 2019
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Apr 24, 2020
#1
  • Apr 24, 2020
  • #1
After a very long and expensive hunt for my issue with my car today I finally found it.After changing every sensor,fuel pump, injectors , ignition system etc etc .... I decided hey why not change the MAF even though I didn’t have codes coming up all symptoms I read on here added up.I bought a new Delphi MAF on rockauto popped it in and never made it out the driveway!! Every time I’d push the accelerator it would stall or knock then stall so in other words my previous problem x10.
So I opened the hood unplugged the new MAF and she runs like a champ at all rpm although she now runs pig rich.So just so everyone knows I have a BBK cold air intake that came with the car , old MAF was a walker new one Delphi , old one makes her run bad sometimes ,new one makes her not even leave the driveway.....so I’m totally lost now as to why none of these MAFs are working . What can I do now?
 
D

Deleted member 215073

Apr 24, 2020
#2
  • Apr 24, 2020
  • #2
Try to find an OEM one from a salvage yard. Or find one from a '94-'95 Mustang and use it to see if your issue goes away. You won't be able to use your air cleaner with the one from a SN95 Mustang but it will let you know if you're on the right path.

FWIW, I went and found a MAF housing from '94-'95 T-Bird, a MAF sensor from a '94-'95 Mustang and combined the two. It works great and looks factory, it even bolts up to the same bracket. It also increased the size of the housing to 70mm.
 

vristang

15 Year Member
Mar 31, 2005
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Apr 24, 2020
#3
  • Apr 24, 2020
  • #3
Unplugging the MAF puts the computer into closed loop control, meaning the ecu is using look up tables for fueling, and guessing at what the airflow actually is.
Unplugging the MAF does not provide any reliable data regarding how the MAF itself is working. The best it can do is confirm that closed loop fuel control is not working properly.
The exact same thing would be true if you unplugged the O2 sensor...

Sorry to give bad news, but most likely, the issue isn't MAF related. Keep working on it, you will get it sorted out...
 

Blown88GT

Founding Member
Nov 13, 1999
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Apr 24, 2020
#4
  • Apr 24, 2020
  • #4
vristang said:
Unplugging the MAF puts the computer into closed loop control, meaning the ecu is using look up tables for fueling, and guessing at what the airflow actually is.
Unplugging the MAF does not provide any reliable data regarding how the MAF itself is working. The best it can do is confirm that closed loop fuel control is not working properly.
The exact same thing would be true if you unplugged the O2 sensor...

Sorry to give bad news, but most likely, the issue isn't MAF related. Keep working on it, you will get it sorted out...
Click to expand...
Unplugging the MAF puts the computer into open loop control.
 
Reactions: vristang
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Canadianfox

Member
Aug 18, 2019
32
2
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Montreal
Apr 24, 2020
#5
  • Apr 24, 2020
  • #5
Damn guys now I’m even more confused so it may not even be a MAF issue ?
 
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Canadianfox

Member
Aug 18, 2019
32
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Montreal
Apr 24, 2020
#6
  • Apr 24, 2020
  • #6
On the old MAF it would be very random I’d be driving and bam knocking no power ,then in 30sec drives like a dream , it was like a switch going on and off
 

Olivethefet

I will own your nuts! LOL
5 Year Member
May 17, 2018
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Apr 24, 2020
#7
  • Apr 24, 2020
  • #7
Have you pulled the computer and checked capacitors? I know its random, but these this are at an age where they give up the ghost and it makes the car do weird things. Just a thought.
 

General karthief

wonder how much it would cost to ship you a pair
5 Year Member
Aug 25, 2016
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Apr 24, 2020
#8
  • Apr 24, 2020
  • #8
These other members may be up on what you are working on and what you have already done but here's the thing, sounds to me like you have wasted time and money not fixing the issue.
I not as good a mechanic as most others on here but I do know where to look and how to diagnose most problems on the fox eec v system. You have to be methodical.
You should have started here:

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
I will say if you have replaced all the sensors then you likely have a computer or wiring problem.
 

7991LXnSHO

wanna catch the space herp
10 Year Member
Sep 1, 2010
7,387
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Kearney, NE
Nov 7, 2020
#9
  • Nov 7, 2020
  • #9
The list gets to checking out the MAF, but please start at the top.
Delphi electronics are a premium, OEM supplier. I would suspect wiring or connections first.
If your BBK meter is not matched to your injectors rating, it will run badly,
 

Noobz347

Stangnet Facilities Maint Tech... Er... Janitor
Admin Dude
Jan 4, 1985
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Jul 11, 2025
#10
  • Jul 11, 2025
  • #10
Zero responses or feedback from suggestions made in this thread.

It must be resolved.


 
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