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Overheating Very Quickly

  • Thread starter Thread starter m3x1c0
  • Start date Start date May 29, 2015
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stang89bidges

Advanced Member
Mar 14, 2014
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Fort Worth Texas
Aug 2, 2015
#101
  • Aug 2, 2015
  • #101
I subscribe to LMR YouTube channel. This just posted recently. Very interesting. Never seen this method performed before.

View: https://youtu.be/5MjAxnGeGKw
 
Reactions: Noobz347

m3x1c0

Member
Oct 24, 2013
76
2
9
Aug 4, 2015
#102
  • Aug 4, 2015
  • #102
Alright Got everything back together and it fired right up! unfortunately I have a pretty steady backfire/ pop out of the exhaust while its idling. It just goes pop pop pop for a few minutes and then stops as soon as I rev it. IT also gets less frequent as it idles. A few things I have to check: I'm pretty sure I have the distributor turned just slightly too far clockwise so I'll pull that back a bit. Second: I'm not positive I have all the plug wires in the correct place, i'll have to check them. Finally, one vacuum line in particular may not be in the correct place. Plus I'll have to go through and make sure all my sensors are hooked up. I wish I knew how this thing was tuned. It has some sort of custom ecu with a knob for different performance levels in the glovebox. There is no wideband hooked up but it was tuned with a program called Tweecer and I was told not to worry as long as the o2 sensors were hooked up. By the way there are 3 o2 sensors. Cleaning up the wiring and getting it tuned up with a wideband will be my next step once I get the thing to run without overheating.

Oh and one more thing! The header gaskets I reused were marginal at best and one of them is definitely not sealing right. So I put the headers on without about half of the required screws until I can get new gaskets today. Could that be the cause of the pop? Esp. since it goes away with revs.
 
Last edited: Aug 4, 2015

squeak93

15 Year Member
Jun 2, 2005
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Joplin, Missouri
Aug 4, 2015
#103
  • Aug 4, 2015
  • #103
Hard to say if the exhaust leak is bad enough to pop or if you have a timing issue. Do you happen to have the dizzy one tooth off?
 

m3x1c0

Member
Oct 24, 2013
76
2
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Aug 4, 2015
#104
  • Aug 4, 2015
  • #104
squeak93 said:
Hard to say if the exhaust leak is bad enough to pop or if you have a timing issue. Do you happen to have the dizzy one tooth off?
Click to expand...

Not according to the (now very faded) marks I made. I could always step it back and see if it goes away.
 

stang89bidges

Advanced Member
Mar 14, 2014
727
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Fort Worth Texas
Aug 4, 2015
#105
  • Aug 4, 2015
  • #105
That's great to see you have everything back together and she fired right up!

Yep get all those things checked first and I'm guessing you will find the culprit.

Watching your video it sounds like it's building pressure somewhere and the backfire is the release. Like those loose headers are not able to hold the pressure too long. But start by making sure your dizzy is dropped in correctly at TDC and work your way down the list.

 

m3x1c0

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Oct 24, 2013
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Aug 4, 2015
#106
  • Aug 4, 2015
  • #106
I looked at a few diagrams like that and have come to the conclusion that the po had no idea what he is doing. There are number markings on the plugs and on the cap. The cap has number 1 down
 

stang89bidges

Advanced Member
Mar 14, 2014
727
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Aug 4, 2015
#107
  • Aug 4, 2015
  • #107
Unfortunately you find PO's like that. Get those wires and dizzy correct fo sho! Then before you know it you be like
 

m3x1c0

Member
Oct 24, 2013
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Aug 4, 2015
#108
  • Aug 4, 2015
  • #108
I looked at a few diagrams like that and have come to the conclusion that the po had no idea what he is doing. There are number markings on the plugs and on the cap. The cap has number 1 down near the front of the motor:

The. Going counter-clockwise the order written on the cap is 12346785... Wtf?!

Not to worry the wires aren't corresponding to the cap numbers in fact they are hooked up where the number 1 is in the correct position according to that diagram near the driver side valve cover

I looked up a few diagrams and noticed that there is a difference between the standard and HO firing order. Standard is 1-5-4-2-6-3-7-8. The HO order goes 1-3-7-2-6-5-4-8. So which one do I use? Either way my firing order as indicated on the plug wires is 1-4-7-2-... I stopped in frustration and confusion from there.

I decided to try and just do it myself so I put my finger on cylinder 1 while turning the crank to feel for the compression stroke, then I made sure the crank was at 0 degrees. Looked at the rotor to see which plug terminal would be number one and it appears to be in between two terminals:


Is the distributor not stabbed in correctly? Is my engine a standard or HO firing order?
 

stang89bidges

Advanced Member
Mar 14, 2014
727
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Aug 4, 2015
#109
  • Aug 4, 2015
  • #109
jrichker said:
This doesn’t prove that the block is HO. Some trucks evidently use a HO firing order
with a low lift cam. However, it will definitely prove that a block can’t be HO because the firing order is wrong.


Remove the #1 & #3 spark plugs. Put your finger in #1 spark plug hole. Crank the engine over until you feel compression on #1 cylinder. Slowly turn the engine until the TDC mark and the timing pointer line up. Mark TDC on the balancer with chalk or paint. Put your finger in #3 spark plug hole and crank the engine 90 degrees. You should feel pressure trying to blow past your finger. If you do not feel pressure, repeat the process again. If you feel pressure, it is a HO engine.

No pressure the second time, remove spark plug #5. Put your finger in #1 spark plug hole. Crank the engine over until you feel compression on #1 cylinder. Put your finger in #5 spark plug hole and crank the engine 90 degrees. If you feel pressure now, the engine is not a HO model, no matter what it says on the engine.

Using a small carpenter or machinist square to mark the harmonic balancer off into 90 degree sections may be helpful here.

A 15/16 deep socket & breaker bar or ratchet may be used to turn the engine.

The HO firing order is 1-3-7-2-6-5-4-8.
Non HO firing order is 1-5-4-2-6-3-7-8
Click to expand...
 

stang89bidges

Advanced Member
Mar 14, 2014
727
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74
Fort Worth Texas
Aug 4, 2015
#110
  • Aug 4, 2015
  • #110
That last post should help. I doubt the car would run that good, or at all, if you weren't close with dizzy and wires.

When you stab dizzy correctly at TDC compression stroke, not exhaust stroke, the rotor should point directly at number 1 spark plug on cap.
 

m3x1c0

Member
Oct 24, 2013
76
2
9
Aug 5, 2015
#111
  • Aug 5, 2015
  • #111
So I must have screwed up the stab since the rotor isnt pointing at anything?
 

m3x1c0

Member
Oct 24, 2013
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Aug 5, 2015
#112
  • Aug 5, 2015
  • #112
Wait since the crank is at TDC and I verified the piston was on the compression stroke (blew my thumb right off the hole.) Couldnt I just turn the housing until one of the plugs is right over the rotor? Then from there I would label that plug #1 and then label the rest counter-clockwise going in the firing order?
 

90sickfox

Wasn't a pretty sight...and I've got big hands
SN Certified Technician
Mar 2, 2015
6,945
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Aug 5, 2015
#113
  • Aug 5, 2015
  • #113
Correct....and your car should have the ho firing order...all mustangs do.
 

m3x1c0

Member
Oct 24, 2013
76
2
9
Aug 5, 2015
#114
  • Aug 5, 2015
  • #114
90sickfox said:
Correct....and your car should have the ho firing order...all mustangs do.
Click to expand...
Thanks! I'm just going to ignore the po's markings and do this and it should be done right
 

stang89bidges

Advanced Member
Mar 14, 2014
727
144
74
Fort Worth Texas
Aug 5, 2015
#115
  • Aug 5, 2015
  • #115
If your redoing everything that should work lol. Never thought about it that way...

Firing order will be your necessary constant.

And watch the 2 dist cap brackets and TFI module. You want those free of any obstacles so you can spin the dizzy comfortably during timing the engine.
 

m3x1c0

Member
Oct 24, 2013
76
2
9
Aug 5, 2015
#116
  • Aug 5, 2015
  • #116
stang89bidges said:
If your redoing everything that should work lol. Never thought about it that way...

Firing order will be your necessary constant.

And watch the 2 dist cap brackets and TFI module. You want those free of any obstacles so you can spin the dizzy comfortably during timing the engine.
Click to expand...

I have to time it? Im not restabbing the dist. Just twisting the cap.
 

m3x1c0

Member
Oct 24, 2013
76
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Aug 5, 2015
#117
  • Aug 5, 2015
  • #117
Wouldn't I just have to set initial timing? so like set the rotor to number one at 11 degrees After TDC?
 

stang89bidges

Advanced Member
Mar 14, 2014
727
144
74
Fort Worth Texas
Aug 5, 2015
#118
  • Aug 5, 2015
  • #118
Um, yes. I'm assuming you don't have a light? If not I dont know if you can get it correct enough to drive much. You can get it close I'm sure but you really need to time it properly before you run any kind of RPM's out of her.
 

stang89bidges

Advanced Member
Mar 14, 2014
727
144
74
Fort Worth Texas
Aug 5, 2015
#119
  • Aug 5, 2015
  • #119
I know the TFI and ECU will adjust as necessary but honestly I don't know how well it will do. I think you can still damage your engine if ran hard, etc.
 

m3x1c0

Member
Oct 24, 2013
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Aug 5, 2015
#120
  • Aug 5, 2015
  • #120
Ok My plan is to line up the rotor at 10 degrees Before TDC like in this vid: View: https://www.youtube.com/watch?v=FHX1yXVyIMg
. I just want to get it close enough to run it around town and make sure everything works. Ill set timing with a light before running it at all. Im nervous that it will still leak coolant since I couldnt find a real reason for it happening. Is 10 degrees BTDC correct for our engines?
 
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