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I dont understand 'fine"

what did the meter read? i know of no meter that says 'fine' on the display

lets get freagan precise here, diagnosis over the web is hard enough
 

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Discussion Starter · #22 ·
idk i read online anything lower than .2 volts when touching the red to engine and black to battery negative terminal at 20v on the meter off and car running is good
 

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Discussion Starter · #23 ·
I plugged my obd tool into my 99 gt(my other mustang) to compare live readings but this time it didn't give me the option to view fuel pressure so i'm assuming the 110psi i was getting on the 03 gt was just the obd tool giving me BS info. the MAF, absolute throttle position, intake air temp, and coolant temp all read the same so its none of those sensors
 

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idk i read online anything lower than .2 volts when touching the red to engine and black to battery negative terminal at 20v on the meter off and car running is good
with the car running, and one lead on the block and the other lead at battery neg

that only tells you from the block to the battery

you have to go from sensor negative to the battery negative.

you have to backprobe the sensor or use a piercing tool
 

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I plugged my obd tool into my 99 gt(my other mustang) to compare live readings but this time it didn't give me the option to view fuel pressure so i'm assuming the 110psi i was getting on the 03 gt was just the obd tool giving me BS info. the MAF, absolute throttle position, intake air temp, and coolant temp all read the same so its none of those sensors

that is not a correct assumption

you are dealing with your car, not the other,

shall we just ignore this called " BS info"?? and not test it?
 

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Discussion Starter · #27 ·
I figured it out, the replacement fuel injectors I got were crap. I tried the injectors from my 99 and it ran fine but also lean under throttle. I did more research(Mustang Stock Fuel Injector Size Chart - LMR.com) and from 87-02 every GT uses 19lbs/hr but the 03/04 are the only years to use 21lb/hr EV1 therefore it's super hard to find. The engine ran lean with the 19lbs/hr because the ECM is tuned for 21lbs/hr. So I swapped back in my stock injectors. Of course the misfire came back so I took out my live data and noticed in bank two the fuel trims were basically perfect staying within +5 and -5 on short term and long term but on bank 1 it was +10 to +25 on short and long term so it seems one fuel injector may be clogged or something causing a lean condition due to not enough fuel in the mixture so the o2 sensor compensates by adding fuel hence the fuel trim. More research shows that quality fuel injectors are EXPENSIVE not to mention very hard to find for my specific year so I was looking into fuel injector service. With the ultrasonic cleaning and electrical testing and everything. Does that sound like the right thing to do?
 

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Discussion Starter · #28 ·
Also a lot of other people who used the crap injectors I bought said it also caused a rich condition like mine.
 

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why did you replace the factory injectors in the first place?
 

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Discussion Starter · #30 ·
The car had a misfire so I changed the spark plugs, COPs, and injectors which fixed the issue. I needed new spark plugs anyway but I didn't know if it was the injectors or COPs causing the mis so I bought both. Come to find out it was an injector.
 

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so you are saying, after all this, you need just one injector?

and you know its the injector because you put it in a different cylinder and that misfire followed the injector?
 
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