Really Bad Skip

foxbodymike87

Active Member
Jul 12, 2011
739
35
39
I recently bought a 93 2.3 mustang with 89k on it. Has a huge skip. I checked the entire ignition system and its all good. Im going to check vacuum lines then after that idk where to look. Do these engines have this kind of problem?? It sounds and shakes like its running on 2 cylinders and can barely make it up small hills from the lack of power.
 
  • Sponsors (?)


I would also check out both coil packs, and the ICM. Also check the wiring going to the coil packs. It almost sounds like one of the packs is dead, as there are two main sparks, and two waste sparks coming out of each pack. The waste spark fires after TDC so that would almost act like a two cylinder miss. Just a thought.
 
You need to have spark, fuel, and compression. If you have double checked that the ignition system is working properly, then check compression. Compression should be pretty even all across.

Can you narrow down which cylinders are not firing? That would be helpful. If you have low compression on two adjacent cylinders then I would lean towards a blown head gasket.

If the compression is good, then I would check the fuel injectors.
 
Being that this is a dual plug head, are both cylinder 2 plugs in the same condition? Can you verify that those plugs are sparking? I would definitely put at least a fresh plug in the drivers side and see if it clears up the running problem. However...

The anti-freeze smell is very concerning, and very typical with a blown head gasket. Read this for some information...

http://easyautodiagnostics.com/ford/head_gasket/2.3L/head_gasket_test_1.php

I am still leaning towards a blown head gasket, but there is the (remote IMO) possibility that you actually could have a bad intake gasket. It could explain some of the symptoms that you are describing. The good news is that on the way down to doing the head, you pull off the intake anyway. If the gasket looks like a problem, then you might decide to put a new one on and see what happens. If not, then continue on down to the head gasket.

My main point here is that if you have a plug that smells like antifreeze, there is only three ways for that to happen. First, coolant leaking into the combustion chamber from the headgasket. Second, coolant introduced into the combustion chamber from a water passage from the intake, due to either a cracked intake or failed intake gasket. Third, you dipped the plug in anti-freeze before you put it in the engine :)

The oil soaking is most likely the result of the plug being fouled by the anti-freeze and no longer firing, leading to it then being covered in oil.
 
Did headgasket. Put everything together and now wont start. I triple checked everything and it wont go. It cranks and starts to sound like it wants to go but it wont. Help?
 
Are you sure you have it timed right?

Do you have fuel? Do you have spark?

When you did the head gasket, could you see that it was blown? You can usually see the tearing or missing section of the gasket.

If you have fuel and spark, and you are sure it is in time, then it could be an electrical issue. I don't want to start just guessing at it, we need data. You could have a bad fuel pump, crank sensor, plugged fuel filter, etc.
 
Head gasket was fine..new infact. But there wad no intake manifold gasket so thats why it ran like crap. I have compression fuel and spark and just replaced icm to see if it was that. When i spray ether down the intake it back fires threw the intake.
 
It really sounds like the timing is off. Backfiring out the intake and sounding like it wants to go is classic timing symptoms. This is an ignition problem in my opinion...

Double check that you have the firing order correct.
firingorder2.jpg



From Jrichker (for the 5.0L but the principle is the same)

Backfiring out the intake is either a valve stuck open or a lean mixture or spark plug wire(s) connected to the wrong cylinder(s). Check compression on all cylinders and then look for vacuum hoses loose, cracked, or misconnected. Check the line for the vapor recirculation system – it is easy to knock loose and not see it when you connect the air pump plumbing. If the vacuum line for the EGR valve and the air pump are cross connected, some very strange things can happen. Check the mass air flow electrical connection and see that it is tight, the same goes for the fuel injection wiring harness connectors.


Does your tach register while cranking? Does it act strangely?

Can you pull any codes at all?
 

Attachments

  • firingorder2.jpg
    firingorder2.jpg
    22.8 KB · Views: 131