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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • Fox 5.0 Mustang Tech

new engine - runs HORRIBLE

  • Thread starter Thread starter JMD Engineering
  • Start date Start date Aug 12, 2006
J

JMD Engineering

New Member
Dec 8, 2004
102
0
0
Northern VA
Aug 12, 2006
#1
  • Aug 12, 2006
  • #1
im chasing my tail. installed RNH 347. had to work out some firing issues (dizzy 180 out/firing order/messed up MSD box). after doing so, the car ran OK. it missed and would hold idle sometimes - but it ran. I figured it was because the valves need to adjusted.

trackheat heads, stock (new) lifters, 1.7 scorpion roller rockers.

lone behold, i tested via exhaust/paper.. that one or more exhuast valves were staying open. so - i go to adjust. i use FTI's adjusting techniques - 0 lash, .5 turn on adjuster nut, tighten locking nut. fire it up - its surges and then dies.. and when i try to give it gas it dies and back fires.

I originally thought i mixed up some wires, so i double checked. nothing. checked all electrical connections and nothing is apparent.

where do i start now ? i just want it to run
 

86mustang5.oh

New Member
Apr 5, 2005
125
0
0
battle creek mi.
Aug 13, 2006
#2
  • Aug 13, 2006
  • #2
map sensor
 

ExplodingGopher

New Member
Jun 11, 2004
517
0
0
The mistake on the lake (Ohio)
Aug 13, 2006
#3
  • Aug 13, 2006
  • #3
dumb question, did you adjust that and all the valves on the compression stroke? I know when i adjust my 460 theres a certain sequence i have to adjust in then turn the crank by hand 90* after each valve is set. The general rule is 1/2-3/4 of a turn past zero lash.
 
J

JMD Engineering

New Member
Dec 8, 2004
102
0
0
Northern VA
Aug 13, 2006
#4
  • Aug 13, 2006
  • #4
ExplodingGopher said:
dumb question, did you adjust that and all the valves on the compression stroke? I know when i adjust my 460 theres a certain sequence i have to adjust in then turn the crank by hand 90* after each valve is set. The general rule is 1/2-3/4 of a turn past zero lash.
Click to expand...

I adjusted according to FTI's website - wait for exhaust to open, adjust intake / wait for intake to almost close, adjust exhaust.
 

91lxttrim

New Member
Mar 7, 2006
194
0
0
AZ
Aug 27, 2006
#5
  • Aug 27, 2006
  • #5
JMD Engineering said:
I adjusted according to FTI's website - wait for exhaust to open, adjust intake / wait for intake to almost close, adjust exhaust.
Click to expand...

I just did mine the same way (TF 1.6 roller rockers), but did you do them in the firing order sequence? I just did mine 1,2,3,4,5,6,7,8. Beginning to think I should have done it in firing order. Does it matter if it's on compression stroke or not?

When I'm at low rpm it stumbles but if I hit half throttle it smoothes out. Also does yours smell like it's running rich?
 

whtpny

New Member
Dec 8, 2002
338
0
0
Spokane WA.
Aug 27, 2006
#6
  • Aug 27, 2006
  • #6
Yes, do it in firing order. You may just want to loosen it all up and start over.
 

91lxttrim

New Member
Mar 7, 2006
194
0
0
AZ
Aug 27, 2006
#7
  • Aug 27, 2006
  • #7
@#$%!!!!!
 

91lxttrim

New Member
Mar 7, 2006
194
0
0
AZ
Aug 27, 2006
#8
  • Aug 27, 2006
  • #8
JMD Engineering said:
I adjusted according to FTI's website - wait for exhaust to open, adjust intake / wait for intake to almost close, adjust exhaust.
Click to expand...

Who's FTI? What's their website?
 

gcwh02

New Member
Jun 20, 2005
515
0
0
pottstown, PA
Aug 27, 2006
#9
  • Aug 27, 2006
  • #9
sounds like it could be a TPS problem
 
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