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Fox Hotter spark???

  • Thread starter Thread starter BeaverMeat
  • Start date Start date Oct 31, 2021
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BeaverMeat

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Oct 31, 2021
#1
  • Oct 31, 2021
  • #1
The car smells like unburnt fuel and most noticeable in open loop. It's not horrible, it just stinks. The cats/pump have been removed and have read this is a normal symptom with the 5.0. The engine is stock except for short headers, BBK 70mm TB, and custom intake. New Motortcraft fuel pressure regulator and refurbished injectors were done. No codes except for 67 (clutch) and 95 (fuel pump secondary circuit)... which will eventually be fixed with some wiring when I get around to it.

Wondering if changing to a hotter spark plug or different gap will help burn the unburnt fuel.

Currently running Autolite 25s.

Would it be ok to switch to 26s?

Any input?
 

General karthief

wonder how much it would cost to ship you a pair
5 Year Member
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Oct 31, 2021
#2
  • Oct 31, 2021
  • #2
My opinion would be the missing cats.
Have you pulled a plug to see if it's dark?
 
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7991LXnSHO

wanna catch the space herp
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#3
  • Oct 31, 2021
  • #3
If the car is running rich, hotter plugs might stay cleaner longer. But it will not clean up the extra fuel.
After carefully going through the surging idle checklist (including cleaning and tightening the salt and pepper shakers, having the computer serviced, fixing vac lines, adding the other smog parts and the air pump back etc.), my 5.0 did not smell of fuel any more than my pre-cat cars. Before that, It stank at idle.
I suggest following the list carefully to make sure your car is running its best. The list is like a full health checkup for your car.

(I did add a high flow catted x pipe back after it was running well to quiet it down some more.)
 
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BeaverMeat

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Nov 2, 2021
#4
  • Nov 2, 2021
  • #4
Cant put the cats back in, per se... Its a 5.0 swapped Volvo and there isn't enough room for cats on the custom exhaust currently. The plan is to redo the exhaust eventually.

I'll have to take a close look at the vacuum system. I do hear a "whine" that starts when come to a stop.
 
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BeaverMeat

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Nov 4, 2021
#5
  • Nov 4, 2021
  • #5
Dumbass question… how should the vacuum hoses be routed into the EVR (EGR vacuum control)? I think I had it hooked up backwards.

The vacuum system has been simplified after the smog pump removal so I don’t have the tree or the reservoir. It’s just manifold to FPR and manifold to EVR/EGR.

The vacuum source line from the manifold should connect to which EVR connector stud? The long or short one?
 

mikestang63

SN Certified Technician
Aug 27, 2012
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Nov 4, 2021
#6
  • Nov 4, 2021
  • #6
@jrichker for the EGR vacuum routing please

The rich smell is because of the removed cats. Either live with it or put newer style cats in that dont require an air pump.
 
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BeaverMeat

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#7
  • Nov 4, 2021
  • #7
mikestang63 said:
@jrichker for the EGR vacuum routing please

The rich smell is because of the removed cats. Either live with it or put newer style cats in that dont require an air pump.
Click to expand...

I’m aware if that… it’s a bit stinkier than usual and my mileage sucks.

When I was cleaning up the engine bay I did notice I installed the vapour purge solenoid backwards because I flipped it over. Doh! So that got me thinking that I also crossed the EVR hoses.

I’ve stared at diagrams already and they don’t specify which connector goes where.

The vacuum block is removed along with the nylon lines.
 

7991LXnSHO

wanna catch the space herp
10 Year Member
Sep 1, 2010
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Nov 4, 2021
#8
  • Nov 4, 2021
  • #8
If your mileage sucks, it might not just be because of missing cats. Is it eye watering, don’t smoke in the garage rich? That’s not just the cats. Do the checklist top to bottom.
 
Last edited: Nov 4, 2021
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BeaverMeat

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#9
  • Nov 4, 2021
  • #9
7991LXnSHO said:
If your mileage sucks, it might not just be because of missing cats. Is eye watering, don’t smoke in the garage rich? That’s not just the cats. Do the checklist top to bottom.
Click to expand...

Working my way through it… at the vac line stage. Nylon tubes were shot and lines replaced.

Just got to figure out this VGR thing…
 
W

waxman

20+ Year Stangneter
Aug 6, 2004
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central il
Nov 4, 2021
#10
  • Nov 4, 2021
  • #10
i had a simular deal,but on a 2.3. put new computer temp sensors and air temp sensor,mpg went up 6 mpg
 

General karthief

wonder how much it would cost to ship you a pair
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#11
  • Nov 5, 2021
  • #11
http://www.veryuseful.com/mustang/tech/engine/images/88Stang5.0Vacuum.gif
 
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BeaverMeat

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#12
  • Nov 5, 2021
  • #12
General karthief said:
http://www.veryuseful.com/mustang/tech/engine/images/88Stang5.0Vacuum.gif
Click to expand...

That one wasn’t helpful. I used the one I attached. I guess the longer connector stud goes to the manifold and the short connector stud goes to the EGR.

Replacing the vacuum lines and rotating the purge solenoid to the correct orientation fixed the problem. Now there is only a slight fuel smell. I’d say the majority of the smell was coming from that fuel tank… now the fumes are getting sucked into the engine as designed.
 

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mattys91gt

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Feb 3, 2022
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Jul 11, 2022
#13
  • Jul 11, 2022
  • #13
BeaverMeat said:
That one wasn’t helpful. I used the one I attached. I guess the longer connector stud goes to the manifold and the short connector stud goes to the EGR.

Replacing the vacuum lines and rotating the purge solenoid to the correct orientation fixed the problem. Now there is only a slight fuel smell. I’d say the majority of the smell was coming from that fuel tank… now the fumes are getting sucked into the engine as designed.
Click to expand...
did you figure the vacuum lines out I still can't figure out what to do with a few lines since I took the EGR off till I can get a new one it snapped where the bolt goes anyone got a cheap one to sell or can tell me how the go
 
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