Big problem and no idea what to do.

Feb 26, 2020
15
2
13
47459
I have a 91 Mustang GT with gt40 intake manifold and gt40p heads. It seems to me that something is causing the car to add to much fuel and advancing the timing way to much and at about 1,500 to 2,000 rpm it just backfires and spits and sputters and does not go further than 2,000 rpm. When i got the car i had noticed the maf sensor was unplugged and all the problems started when i plugged it in . I have been running in circles since February since i got the car and at this point anything helps.
 
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General karthief

wonder how much it would cost to ship you a pair
Mod Dude
Aug 25, 2016
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polk county florida
I take it you bought it this way,
go here and do this checklist step by step, don't skip around.
Post here any questions you have.
 

Potomus Pete

Gretchen Whitmer is eating at me
Mar 7, 2019
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Sarasota Florida
Its going to be some work to figure it out. We have all been there with the list. Sounds messy I would consider finding a Mustang expert only because you seem to know a little about cars, but your problem seems like you need specialized diagnostics . Get it going and start fresh. Just my opinion from when my car was messed up and I tried everything.....It was the PIP
 

Potomus Pete

Gretchen Whitmer is eating at me
Mar 7, 2019
1,334
454
93
56
Sarasota Florida
Gas cutting out at 2000 rpm maybe?? You do have to do the checklist no fun whatsoever I would assume you have read more tech on fixin your car, so your at a crossroads. An old fashioned mechanic who knows old cars could figure it out in a couple of hours you just have to ask around. JUST MY OPINION
 
Feb 26, 2020
15
2
13
47459
Gas cutting out at 2000 rpm maybe?? You do have to do the checklist no fun whatsoever I would assume you have read more tech on fixin your car, so your at a crossroads. An old fashioned mechanic who knows old cars could figure it out in a couple of hours you just have to ask around. JUST MY OPINION
Will do the checklist and talk to some older mechanics thanks for the help.
 

2000xp8

SN Certified Technician
Aug 8, 2003
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NJ
If you can get your hands on a spare meter (assuming it still has a stock meter and injectors), try swapping it in. While it's no guarantee, in my experience when a vehicle runs better without the meter, the meter itself has been the problem.
 
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