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Backfiring after head swap...........

  • Thread starter Thread starter mbsprinks281
  • Start date Start date May 4, 2005

mbsprinks281

Member
Apr 19, 2005
58
2
9
Lockport, IL
May 4, 2005
#1
  • May 4, 2005
  • #1
Cant even get it started. The timing has to be off, right?
 

jaymac

New Member
Feb 18, 2004
995
0
0
Northern Mass
May 4, 2005
#2
  • May 4, 2005
  • #2
sounds like the problem.
Have you checked it?
You have fuel pressure?
It won't start, but it will backfire trying?
Have you checked/adjusted the timing w/ a light?
 

mustangramair

Member
Feb 24, 2004
326
0
17
Iowa
May 4, 2005
#3
  • May 4, 2005
  • #3
I just had the same exact problem. Mine was out of time, got it timed and it still acted this way. Then i talked to trick flow and i had the wrong rocker arms, made it run better but still not well. Came to find out a vaccum fitting on the underside of the explorer intake was hitting my valve covers so i had a 1/4 of an inch gap between the upper and lower intake and now it runs great. But yeah i would check your timing and see if it is correct.
 

mbsprinks281

Member
Apr 19, 2005
58
2
9
Lockport, IL
May 4, 2005
#4
  • May 4, 2005
  • #4
Have fuel pressure, have spark. When I try and turn it over it backfire through the intake, and wont start. I guess Ill have to crank her manually back to top dead center and drop the dizzy back in again.....
 

04sleeper

Founding Member
Jun 22, 2002
2,674
14
89
Dallas, TX
May 4, 2005
#5
  • May 4, 2005
  • #5
mbsprinks281 said:
Have fuel pressure, have spark. When I try and turn it over it backfire through the intake, and wont start. I guess Ill have to crank her manually back to top dead center and drop the dizzy back in again.....
Click to expand...
Thats what I would try first.
 
S

Scorcher2005

Member
Apr 17, 2004
883
0
16
South Carolina
May 4, 2005
#6
  • May 4, 2005
  • #6
have the right firing order?
 

5spd GT

"the 5.0 owns all"
Founding Member
Aug 7, 2002
9,516
6
99
Arkansas
May 4, 2005
#7
  • May 4, 2005
  • #7
Yep, check your firing order to make sure it is correct. If that is correct try spinning your distributor clockwise a little bit at a time to see if it will hold idle.

mustangramair- I had a similar occurance for mine except I tightened just enough to break an ear off my upper intake because the pcv two way valve was sitting on top of the valve cover when I went to tighten it down...unneeded stress to say the least
 
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