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Really need help here...

  • Thread starter Thread starter stang1986GT
  • Start date Start date Aug 4, 2008

stang1986GT

Member
Mar 30, 2005
143
0
17
Charleston, WV area
Aug 4, 2008
#1
  • Aug 4, 2008
  • #1
I replaced head gaskets on my 86 5.0. Screwed up and put the distributor in wrong, but I have all that fixed. I have the pointer sitting on "0" and the rotor button is pointing to the #1 spark plug wire perfectly. It's on the compression stroke...double checked that last night.

The car absolutely will not run! It's running very very rich and missing terribly. It wont even idle. What is the deal! I don't see any vacuum leaks, at least nothing that would make it run THIS bad. EGR valve seems to be working. I'm not sure what else to do!

I'm going to do a compression test to make sure I didn't somehow screw up the head gasket install. Other than that, maybe check to see if I accidentally left a rocker loose. If this was the problem, would it still be running rich?

Kind of at the end of my rope here.

Thanks!
 

stang1986GT

Member
Mar 30, 2005
143
0
17
Charleston, WV area
Aug 26, 2008
#2
  • Aug 26, 2008
  • #2
Still can't figure this out. Anyone have any ideas?
 

jrichker

StangNet's favorite TOOL
In Remembrance. Thank you for your contributions
Mar 10, 2000
27,512
2,811
234
Dublin GA
Aug 26, 2008
#3
  • Aug 26, 2008
  • #3
Make sure you have manifold vacuum connected to the MAP sensor. The MAP sensor is mounted on the firewall just above and behind the upper intake manifold.


Diagram courtesy of Tmoss & Stang&2birds


See the following website for some help from Tmoss (diagram designer) & Stang&2Birds (website host) for help on 88-95 wiring Mustang FAQ - Engine Information Everyone should bookmark this site.

Ignition switch wiring
http://www.veryuseful.com/mustang/tech/engine/images/IgnitionSwitchWiring.gif

Fuel, alternator, A/C and ignition wiring
http://www.veryuseful.com/mustang/tech/engine/images/fuel-alt-links-ign-ac.gif

Complete computer, actuator & sensor wiring diagram for 88-91 Mass Air Mustangs
http://www.veryuseful.com/mustang/tech/engine/images/88-91_5.0_EEC_Wiring_Diagram.gif

Vacuum diagram 89-93 Mustangs
http://www.veryuseful.com/mustang/tech/engine/images/mustangFoxFordVacuumDiagram.jpg

HVAC vacuum diagram
http://www.veryuseful.com/mustang/tech/engine/images/Mustang_AC_heat_vacuum_controls.gif

TFI module differences & pinout
http://www.veryuseful.com/mustang/tech/engine/images/TFI_5.0_comparison.gif

Fuse box layout
http://www.veryuseful.com/mustang/tech/engine/images/MustangFuseBox.gif
 

87coupe50

Member
Feb 10, 2008
105
1
16
WAYNESBORO, PA
Aug 26, 2008
#4
  • Aug 26, 2008
  • #4
turn the distributor about a 1/2 - 3/4 inch clockwise to get the timing closer to 10* before TDC and see how it does
 

93 LX

Founding Member
Jun 2, 2000
3,081
3
0
Norwalk, CA.
Aug 26, 2008
#5
  • Aug 26, 2008
  • #5
Recheck TDC, I did something like this and I was 180 out. Remember the crank turns 2 times for one of the cam.
 

SQUEEZE&STROKE

New Member
Jun 24, 2005
0
0
0
SOUTHERN CA
Aug 26, 2008
#6
  • Aug 26, 2008
  • #6
Do you have the firing order correct?
 

skunk21

Active Member
May 22, 2007
1,203
3
36
Taxachusetts
Aug 26, 2008
#7
  • Aug 26, 2008
  • #7
SQUEEZE&STROKE said:
Do you have the firing order correct?
Click to expand...

+1 I was thinking this myself, it could be something as simple has this. you could be 180 like the others stated. take your time and go over every inch if vacuum line, wires and connectors first before you tear it down again, then check and recheck. I missed little stupid stuff on my top end job. reckeck your tdc like 93 LX stated even let it go by a few times to make sure if needed.
 

stang1986GT

Member
Mar 30, 2005
143
0
17
Charleston, WV area
Sep 26, 2008
#8
  • Sep 26, 2008
  • #8
greensvt21 said:
+1 I was thinking this myself, it could be something as simple has this. you could be 180 like the others stated. take your time and go over every inch if vacuum line, wires and connectors first before you tear it down again, then check and recheck. I missed little stupid stuff on my top end job. reckeck your tdc like 93 LX stated even let it go by a few times to make sure if needed.
Click to expand...

I figured out the problem. Stupid stupid mistake. When I tightened down the rocker arms, I did some of them in the wrong sequence, thus getting the wrong torque reading.

I took the valve covers off, and two exhaust on one side, and three exhaust valves on the other side were WAY loose. Lucky the push rod didn't get bent or anything. I readjusted everything, and it runs great. I still need to dial in the timing a little better, but I'm struggling with a nasty exhaust leak now.

Thanks for your help!
 
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