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Fuel 93 5.0 fuel problem

  • Thread starter Thread starter bjohnson6519
  • Start date Start date Apr 27, 2025
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bjohnson6519

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Jun 14, 2025
#61
  • Jun 14, 2025
  • #61
Yes
 

Mcmahst

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Jan 19, 2021
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Laguna Woods CA, fort Mohave AZ
Jun 14, 2025
#62
  • Jun 14, 2025
  • #62
unless I missed it, I think you’re at the stage of removing them and having someone inspect/test/clean them. Like others have said, it could be a bad ground, but each of them ground independently at the ECU. You need someone else to eliminate them as the problem. Just my 2 cents.
 

General karthief

wonder how much it would cost to ship you a pair
5 Year Member
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#63
  • Jun 14, 2025
  • #63
AND CHANGE THE OIL!!!!
Sorry, but you're washing the cylinder walls every time you turn it over.
 
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General karthief

wonder how much it would cost to ship you a pair
5 Year Member
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polk county florida
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#64
  • Jun 14, 2025
  • #64
While you're at it, check the right rear tire pressure, it looks a little low
 
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bjohnson6519

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#65
  • Jun 21, 2025
  • #65
So I decided to do a compression test. Not looking too good. This is a fresh rebuilt engine. Any thoughts? Jump time?
 

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bjohnson6519

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#66
  • Jun 21, 2025
  • #66
Every cylinder is low. I did change oil it was gasoline.
 
Last edited: Jun 21, 2025

Mcmahst

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#67
  • Jun 21, 2025
  • #67
Fresh rebuild? As in bottom end or long block rebuild? Could be timing chain, or valve train. Bring cyl #1 to TDC on the compression stroke, and pump some air into the cylinder, and find out where it is leaking from. You could also just watch the valve action to the timing marks to verify against the cam profile.
 
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General karthief

wonder how much it would cost to ship you a pair
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#68
  • Jun 22, 2025
  • #68
Unless you have a few hundred miles on a 'new' build, things are not seated, just my opinion but I'd squirt a little oil in the cylinders and put some miles on it then compression test it
 
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bjohnson6519

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#69
  • Jun 22, 2025
  • #69
That would be nice but can't run it because it is not burning the fuel. The oil was gasoline, the plugs are wet and blows black smoke.
 

Mcmahst

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Laguna Woods CA, fort Mohave AZ
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#70
  • Jun 22, 2025
  • #70
You’re kinda between a rock and a hard space. You’re counting on a set of rebuilt injectors as good, and trying to diagnose what else could be the problem. While I’m no fan of parts swapping, you might bite the bullet and put a new set of injectors on it. Even at that compression level, the car should start and run. As @General karthief said, you’ve got to get some hours on the engine to verify the compression. Check the valve timing as was suggested before as well. Good luck.
 
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bjohnson6519

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#71
  • Jun 22, 2025
  • #71
Thanks this is not the first time starting the engine. It ran ok before was able to drive it (not a lot )and back it out of the garage. Then this. I did switch one injector I thought was the problem then checked that cylinder and still wet plug.
 

General karthief

wonder how much it would cost to ship you a pair
5 Year Member
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#72
  • Jun 22, 2025
  • #72
Squirt oil in the cylinders, your washing the cylinder walls with all that gas.
Go back over your fuel pressure, swap in some fresh plugs, verify spark.
 
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AeroCoupe

lube between the nut and the face. I know my lubes
Founding Member
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Jun 22, 2025
#73
  • Jun 22, 2025
  • #73
I went back and looked at the pictures and the MAF (sensor and body) is made by Walker. Just me but I would find a stock Ford MAF ( @General karthief ) to eliminate there being a transfer function issue or it just being an aftermarket POS.

Are the injectors actually Ford pieces? eBay and Amazon posted and still post “genuine Bosh” or “genuine Ford” injectors and an high percentage of them are not and are garbage.

The Painless harnesses have been know to have issues but for the most part they are good. You may end up having to ring it out and make sure it’s good to go.

Where are the O2 sensors located in the exhaust? The MAP sensor should not have a vacuum line attached to it so if it does remove that. Did not see a pic of this but wanted to throw that out there.

You should be able to put the accelerator pedal to the floor when cranking and it will put the ECU in the “clear flood” mode.

See this post:

Post in thread '1993 Cobra flooding'
https://stangnet.com/mustang-forums/threads/1993-cobra-flooding.923718/post-9351953
 
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bjohnson6519

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Feb 16, 2019
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Jul 11, 2025
#74
  • Jul 11, 2025
  • #74
I am at my whits end boys. Brand new injectors, brand new ECU, brand new regulator, brand new engine. Still doing the same damn thing.
 

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Last edited: Jul 11, 2025

AeroCoupe

lube between the nut and the face. I know my lubes
Founding Member
Oct 28, 2001
5,833
3,965
183
Claremore, OK
Jul 11, 2025
#75
  • Jul 11, 2025
  • #75
I could kick myself right now but tell me you have this motor on the 351W firing order and not the old non-roller 302W firing order...

This would be 1-3-7-2-6-5-4-8

All roller cam 302W run off the 351W firing order.
 
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bjohnson6519

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Feb 16, 2019
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florida
Jul 11, 2025
#76
  • Jul 11, 2025
  • #76
Yeah firing order is correct 351
 
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AeroCoupe

lube between the nut and the face. I know my lubes
Founding Member
Oct 28, 2001
5,833
3,965
183
Claremore, OK
Jul 11, 2025
#77
  • Jul 11, 2025
  • #77
You have a 50 oz balancer and 50 oz flywheel on it as well, correct? Other quick think to check is to make sure you have the correct connectors on the injectors. Just want to make sure the correct color of wire corresponds to the correct injector.

 
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bjohnson6519

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Feb 16, 2019
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8
florida
Jul 12, 2025
#78
  • Jul 12, 2025
  • #78
Yeah it's a painless wiring harness everything is hooked up correctly
 

AeroCoupe

lube between the nut and the face. I know my lubes
Founding Member
Oct 28, 2001
5,833
3,965
183
Claremore, OK
Jul 12, 2025
#79
  • Jul 12, 2025
  • #79
Not saying you did anything wrong but there have been issues with the painless harnesses in the past with misprinted wires and wires not seated into the connectors all the way.
 
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bjohnson6519

Member
Feb 16, 2019
50
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8
florida
Jul 12, 2025
#80
  • Jul 12, 2025
  • #80
Thing is it was running fine before then it was not. Only thing I can think now is a ground issue or the timing is off. But it does not hold the fuel pressure long it primes up the immediately starts going down. New fuel regulator.
 
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