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Engine 93 mustang engine swap weird fuel pump problem

  • Thread starter Thread starter Cool19971
  • Start date Start date Sep 18, 2020
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Cool19971

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Sep 18, 2020
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Lewisport kentucky
Sep 18, 2020
#1
  • Sep 18, 2020
  • #1
I have a 1993 mustang convertible. It was an 2.3l car. I have swapped a 302 and AOD in it. Currently using 1993 woring hanress and an a9p ecu. The car is having a very weird problem . First time you start it it runs perfect no check engine light at all, if you let it run for awhile and shut it off the next time you turn the key on the fuel pum will be stuck running , if you start the car in this state the car will run horrible and have a constant check engine on . If you wait and flip the key on and off multiple times once the fuel pump primes correctly again and you start the car it once again runs perfect . I have had the ecu repaired and that made no change . Not sure where to go at this point with it.
 

General karthief

wonder how much it would cost to ship you a pair
5 Year Member
Aug 25, 2016
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polk county florida
Sep 18, 2020
#2
  • Sep 18, 2020
  • #2
4cyl to v8 swaps are tricky, did you check for codes? Did you install all the required grounds in the engine compartment? Is there any other mods done to the car?
 
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Cool19971

New Member
Sep 18, 2020
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1
Lewisport kentucky
Sep 18, 2020
#3
  • Sep 18, 2020
  • #3
General karthief said:
4cyl to v8 swaps are tricky, did you check for codes? Did you install all the required grounds in the engine compartment? Is there any other mods done to the car?
Click to expand...

We cleared out all codes had a bad MAF and bad air charge coolent sensor. When the car runs horrid we cant scan. We have the ground strap, main ecu ground and the ground by the ecu all the other grounds on the car were stock with the 4 cylinder. It depends what you mean by mod exactly we've done several simple things. We also deleted all smog except egr only because we dont have the proper delete parts for it yet. Like I said when it starts correctly and the fuel pump works right the car run perfect
 

General karthief

wonder how much it would cost to ship you a pair
5 Year Member
Aug 25, 2016
27,890
10,550
203
polk county florida
Sep 18, 2020
#4
  • Sep 18, 2020
  • #4
Go through this thread, it should show you important ground locations and there is a section that talks about the fuel pump running on.

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
 
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