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Engine Raw fuel out tail pipe/Codes 42 and 92

  • Thread starter Thread starter TheCaptainAwesome
  • Start date Start date Apr 18, 2022
T

TheCaptainAwesome

Member
Apr 18, 2022
5
5
13
Imboden Ar.
Apr 18, 2022
#1
  • Apr 18, 2022
  • #1
Hello. I actually have a 5.0 in a 68 Ford F100 that I put a mustang fuel injection setup in. It has been quite a journey getting it to this point however I’m having an issue with it starting, and it is running rich. It doesn’t hold pressure at the fuel rail so I have to cycle the ignition to build pressure before I start it. Then as it warms up while running it starts putting gas out of the exhaust pipes enough to make the floor wet. I only have codes 42 and 92 when I do a KOER. When I do a cylinder cutout then the first round it is cyl’s 7,6,5,3. Second round is 6,5,3,1, and 7. Third round is 8,7,6,5,4,3,2, and 1. I used a Ron Francis wiring kit. I bought all new sensors, a reman AL9 ecm, and I’m running a factory fpr. The motor itself has 27,000 miles on it. I bought it remanned from Surefire 4 years ago. It had a 3 year warranty and waited until the warranty was out because I wanted to change heads. It’s an early model 302, and I couldn’t afford to change heads, but I did have to swap the cam out to get the right firing order. It has a 351W flat tappet RV cam. I’ve got a video of it running if that would help anyone. I’m at a loss and desperately need help. Thank you.
 

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General karthief

wonder how much it would cost to ship you a pair
20+ Year Stangneter
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Apr 18, 2022
#2
  • Apr 18, 2022
  • #2
Give is a pic of the engine compartment
 
T

TheCaptainAwesome

Member
Apr 18, 2022
5
5
13
Imboden Ar.
Apr 18, 2022
#3
  • Apr 18, 2022
  • #3
I’ll have to take an updated one when I get to work tomorrow. I redid the air intake and built a cold air box although I don’t have it on atm. The only pic I got is from before I had the compressor on and it was running.
 
T

TheCaptainAwesome

Member
Apr 18, 2022
5
5
13
Imboden Ar.
Apr 18, 2022
#4
  • Apr 18, 2022
  • #4
Nothing is loading for me right now. I do have a video of it running I took today. It won’t upload here, but I could probably email it to you.
 

General karthief

wonder how much it would cost to ship you a pair
20+ Year Stangneter
Aug 25, 2016
27,914
10,562
203
polk county florida
Apr 19, 2022
#5
  • Apr 19, 2022
  • #5
Did you verify that fuel is exiting the tail pipes?
I doubt there is that much condensation in them pipes. Don't run the engine at all and change that oil out asap, squirt some clean motor oil into the cylinders. Now on to the problem.
Oh, and change them plugs!!!!!
What is the static fuel pressure? How is the fuel system setup? In tank pump? Return line? Timing? Injectors firing at the right time?
I'm unfamiliar with the Ron Frances harness.
Does the fuel pump run constantly?
I left this in the fox mustang tech to get some members in on the action.
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,249
17,934
224
Massachusetts
Apr 19, 2022
#6
  • Apr 19, 2022
  • #6
Looks like you have multiple misfires all around. That's why the numbers keep changing. Every cylinder is misfiring for some reason.

So many possible reasons though. Can you tell us about the engine?
 

manicmechanic007

5 Year Member
Sep 26, 2017
2,532
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Roy, Utah
Apr 19, 2022
#7
  • Apr 19, 2022
  • #7
If it does not hold fuel pressure that is where to start
Test each injector individually using a spare rail
Make sure the fuel pressure regulator diaphragm holds vacuum
IMO you have a leaking injector or two
 
T

TheCaptainAwesome

Member
Apr 18, 2022
5
5
13
Imboden Ar.
Apr 19, 2022
#8
  • Apr 19, 2022
  • #8
Test each injector individually using a spare rail
manicmechanic007 said:
Make sure the fuel pressure regulator diaphragm holds vacuum
Click to expand...
I don’t have a spare rail. I do know the fpr is holding vacuum.

General
I installed a tank from a Bronco 2 in the frame and I’m running a stock pump from the bronco 2. Fuel lines from a short bed f150 with a single rear tank and the fuel rail off of a truck. I did that so the fuel lines go out the back and I could use all factory ford parts. Timing is set to 12 degrees with the spout disconnected. Fuel pressure is 40psi and the injectors are firing at the right time. The Ron Francis harness is a little more expensive way of doing this conversion, but it makes it all plug and play. Plug everything into your sensors, hook up 3 wires (hot, key on, and ground), and your good to go. Fuel pump runs long enough to prime then shuts off until it is started.

The engine is a stock early model 302. I purchased it about 4 years ago and it had a 3 year warranty on it. I haven’t done any mods to it other than this fuel injection conversion. I did have to swap the cam out to change to the HO firing order. I wish I could have afforded to swap to a roller cam setup, but I couldn’t squeeze it into the budget. So I’m running a flat tappet RV cam for a 351w, and of course buying stock in a Zinc additive . I’m building this for a daily driver. Because of suspension and wiring upgrades there actually hadn’t been enough miles put on the motor to even wear off all the protective coating on the original cam. I of course did put new lifters in also.

I was going to snap a current pic of the engine today, but my wife got admitted to the hospital last night so I’m not at work today, which is where the truck is. I do have a pic with the plenum off this was mid build. With this pic you can see the fuel rail setup. I’m also putting a reference pic of the truck itself. Just because, well why not? I sure do appreciate all your help.
 
Reactions: Potomus Pete, 2Blue2, 90sickfox and 1 other person

manicmechanic007

5 Year Member
Sep 26, 2017
2,532
713
143
Roy, Utah
Apr 19, 2022
#9
  • Apr 19, 2022
  • #9
Pretty hard to test those injectors without a spare rail
Not one like yours (too hard to plug the fuel ports you are not using)
I use one off a 2.3 Mustang or Ranger
You can shoot fuel injector cleaner thru them and watch the spray pattern
You will not get that far on some of yours because you will have cleaner all over if they leak or drizzle
While at the wrecking yard grab several injectors the same color as yours
 

manicmechanic007

5 Year Member
Sep 26, 2017
2,532
713
143
Roy, Utah
Apr 19, 2022
#10
  • Apr 19, 2022
  • #10
I use fuel (gas) or cleaner to check them
Safer to use injector cleaner (not as volatile)
 

General karthief

wonder how much it would cost to ship you a pair
20+ Year Stangneter
Aug 25, 2016
27,914
10,562
203
polk county florida
Apr 19, 2022
#11
  • Apr 19, 2022
  • #11
TheCaptainAwesome said:
Test each injector individually using a spare rail

I don’t have a spare rail. I do know the fpr is holding vacuum.

General
I installed a tank from a Bronco 2 in the frame and I’m running a stock pump from the bronco 2. Fuel lines from a short bed f150 with a single rear tank and the fuel rail off of a truck. I did that so the fuel lines go out the back and I could use all factory ford parts. Timing is set to 12 degrees with the spout disconnected. Fuel pressure is 40psi and the injectors are firing at the right time. The Ron Francis harness is a little more expensive way of doing this conversion, but it makes it all plug and play. Plug everything into your sensors, hook up 3 wires (hot, key on, and ground), and your good to go. Fuel pump runs long enough to prime then shuts off until it is started.

The engine is a stock early model 302. I purchased it about 4 years ago and it had a 3 year warranty on it. I haven’t done any mods to it other than this fuel injection conversion. I did have to swap the cam out to change to the HO firing order. I wish I could have afforded to swap to a roller cam setup, but I couldn’t squeeze it into the budget. So I’m running a flat tappet RV cam for a 351w, and of course buying stock in a Zinc additive . I’m building this for a daily driver. Because of suspension and wiring upgrades there actually hadn’t been enough miles put on the motor to even wear off all the protective coating on the original cam. I of course did put new lifters in also.

I was going to snap a current pic of the engine today, but my wife got admitted to the hospital last night so I’m not at work today, which is where the truck is. I do have a pic with the plenum off this was mid build. With this pic you can see the fuel rail setup. I’m also putting a reference pic of the truck itself. Just because, well why not? I sure do appreciate all your help.
Click to expand...
Sounds like your are using all the right stuff, fuel system sounds good.
Are the injectors new?
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,249
17,934
224
Massachusetts
Apr 19, 2022
#12
  • Apr 19, 2022
  • #12
What is that fuel rail off of? That's not a typical 86+ Mustang rail.

I don't think it has anything to do with your issue but just trying to understand what parts you used to put this together.
 

General karthief

wonder how much it would cost to ship you a pair
20+ Year Stangneter
Aug 25, 2016
27,914
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203
polk county florida
Apr 19, 2022
#13
  • Apr 19, 2022
  • #13
Looks like an explorer or maybe a rail off a truck engine.
 

manicmechanic007

5 Year Member
Sep 26, 2017
2,532
713
143
Roy, Utah
Apr 19, 2022
#14
  • Apr 19, 2022
  • #14
Yes truck engine rail that sandwiched between intakes
2 gasket beetches
 
M

Monkeybutt2000

Mustang Master
Aug 11, 2019
1,387
849
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Lafayette,IN
Apr 19, 2022
#15
  • Apr 19, 2022
  • #15
Hope those aren't eBay injectors.
 

General karthief

wonder how much it would cost to ship you a pair
20+ Year Stangneter
Aug 25, 2016
27,914
10,562
203
polk county florida
Apr 19, 2022
#16
  • Apr 19, 2022
  • #16
Monkeybutt2000 said:
Hope those aren't eBay injectors.
Click to expand...
I agree, I'd run junk I found on the floor before ebay injectors
 
T

TheCaptainAwesome

Member
Apr 18, 2022
5
5
13
Imboden Ar.
Apr 20, 2022
#17
  • Apr 20, 2022
  • #17
Nope they aren’t eBay injectors, but I’m not sure if they are any better. Rockauto. Oh well. If I get a chance between my daughters t ball then I will try to check that this weekend. I sure appreciate y’all. Here is those current pics I told you I would get. I have a box built that goes around the air filter and seals to the hood. I have it off right now cause it’s kind of in the way when working on it.
 
Reactions: 90sickfox
M

Monkeybutt2000

Mustang Master
Aug 11, 2019
1,387
849
133
Lafayette,IN
Apr 20, 2022
#18
  • Apr 20, 2022
  • #18
Sooo what did these injectors cost?
 

General karthief

wonder how much it would cost to ship you a pair
20+ Year Stangneter
Aug 25, 2016
27,914
10,562
203
polk county florida
Apr 20, 2022
#19
  • Apr 20, 2022
  • #19
Do you remember what brand those squirters were?
looks like a nice swap you got going on there.
 

manicmechanic007

5 Year Member
Sep 26, 2017
2,532
713
143
Roy, Utah
Apr 21, 2022
#20
  • Apr 21, 2022
  • #20
I sell Motocraft and Ford parts online (spoils of war) on ebay
ebay is not bad itself other than the 10 percent they charge to sell
 
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