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  • 1965 - 1973 Classic Mustangs -General/Talk-
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5.0 almost running..few questions though

  • Thread starter Thread starter garycroix
  • Start date Start date Dec 18, 2006
G

garycroix

New Member
Sep 16, 2005
39
0
0
GA, wish it was NC
Dec 18, 2006
#1
  • Dec 18, 2006
  • #1
Finally got the fuel pump to run. I used a 1990's starter solenoid on my 66. When I attempted to start the car for the first time, the starter wouldn't stop turning...had to remove the (+) battery cable to stop the engine from turning over. Looked around this morning, I find that the starter side of the starter solenoid has power, even with key in the 'off' position. This means my solenoid is screwed up, doesn't it? Can I replace it with the 1966 style solenoid?
Also, when key is turned to 'on,' I have no power at the coil. Shouldn't I? I appreciate all the help I can get.

Gary in GA
 

spirockp

5 Year Member
Mar 26, 2004
465
12
39
NJ
Dec 18, 2006
#2
  • Dec 18, 2006
  • #2
Key ON = Power to coil.
 
G

garycroix

New Member
Sep 16, 2005
39
0
0
GA, wish it was NC
Dec 18, 2006
#3
  • Dec 18, 2006
  • #3
Okay, I fixed the coil problem. Trying to start it, I have fuel pressure, and I have spark (used timing light to test). Spark seems intermittent, not steady. What can I look at now, as to why it won't start up? Any codes I should look for?

Thanks in advance.
 

68keyblr

20+ Year Stangneter
Mar 17, 2003
946
20
49
Arizona
Dec 18, 2006
#4
  • Dec 18, 2006
  • #4
Are you running the EEC-IV computer? What codes does it throw?
 
G

garycroix

New Member
Sep 16, 2005
39
0
0
GA, wish it was NC
Dec 18, 2006
#5
  • Dec 18, 2006
  • #5
I got no codes...used a volt meter and an Actron tester. No codes. I am using a Ford Racing EEC-IV computer. What's throwing me the most is the intermittent spark.
 
B

bsedwebt70-5.0

New Member
Jul 1, 2004
320
0
0
Charlottesville, VA
Dec 19, 2006
#6
  • Dec 19, 2006
  • #6
I have a 5.0FI in my 1970 - I had to use the 1993 solenoid to make it all work right - There is a difference in the smaller "mini" starters used in 1992 and 1993 vs. the larger starters used in 1991 and older 5.0's -- you have to run the wires just right or the starter will turn over but seem to hang for 3 seconds after the car starts - if you have that problem search for this in 5.0 tech or under my prior postings - I can't remember at this moment where the big and little starter side wires go on the solenoid - I would have to get to my car and look.
 
B

bsedwebt70-5.0

New Member
Jul 1, 2004
320
0
0
Charlottesville, VA
Dec 19, 2006
#7
  • Dec 19, 2006
  • #7
Oh - if you got it turning over now and it is almost running - those distributors on the 5.0's have a bolt on ignition module that almost always give you trouble - I have a few spares laying around and keep an extra in the car since they go bad so often. Use dielectric grease when installing it to avoid future problems. I have had the same problem with intermittant spark due to this module AND because the hall effect unit inside the dizzy went bad - it took too much effort to try taking it apart so I went to the local AutoZone and got a rebuilt one for $75 or so - problem solved permanantly. Make sure you get one with the right drive gear - steel vs. cast iron - if mismatched then you will have gear wear very quickly. Another thing - make sure when you stab the dizzy into the engine you know where #1 firing is so the dizzy will have the ignition module pointing about 1.5 inches to the right (facing the engine) from the water neck. There is a "lamp shade" with 1 different sized opening that is used to time the injector firing and this is the right place for it when set at 15 degrees advanced (usually the best overall timing setting for power using 91 or better octane) with the spout out. The spout is a 3/4 inch small gray plug that can be removed from the pigtail wire coming off by the distributor. If you do not remove the spout you will not be able to set the base timing as it will jump around. Once you have set the base timing and with the spout back in and checking timing while running you will see the timing jump all over the place - that is supposed to happen - the computer is taking over timing for best power, economy, emmissions, etc... Also - you probably know this but just to be sure - the firing order is different on the HO 5.0 than the old 302 or non HO 5.0. Also - from experience - if the headers glow red in a few minutes after running you are way too retarded on the timing probably because the dizzy needs to be re-stabbed to get the ignition module in that sweet spot 1.5 inches or so near the water neck. Good luck
 

yeloxr7

Member
Apr 18, 2005
429
0
16
Dec 20, 2006
#8
  • Dec 20, 2006
  • #8
Make sure all the grounds are good.

The most important thing I discovered when I did a 5.0 EFI conversion in a 79 Mustang is to make sure that all the wires in the "main" plug are pressed onto their repective pins on the EEC computer. There should be a plastic cover that locks onto the processor box that will accomplish this. you can also use zip ties to hold the cover against the box as well. If the connection is not positive you will have all kinds of intermittent problems.
 
B

bsedwebt70-5.0

New Member
Jul 1, 2004
320
0
0
Charlottesville, VA
Dec 20, 2006
#9
  • Dec 20, 2006
  • #9
you are right - the salt and pepper shakers (10 pin connectors) cause tons of problems - make sure they are clean and tight
 
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