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Another head gasket thread

I just searched for "rough idle" and clicked on first one...he said he gapped his plugs to .054....I put mine at .044 which is what my book says. When I pulled the plugs out, they were WAY wider than .044......

Just realized something....the driver's ex man burned off the oil from my hands which tells me those three are firing......didn't have NEAR the smoke from the passenger side.....I'm gonna swap plugs driver's to passenger.
 



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The thing is, spark plugs HAVE to fire in pairs or they don't fire at all.

Take a look at this:
FiringOrder6a.gif


The firing order is 1, 4, 2, 5, 3, 6. Plugs 1 & 5 fire at the same time, then 4 & 3, then 2 & 6, then 5 & 1, then 3 & 4, then 6 & 2.

The coil isn't grounded so it needs a loop. That loop goes through the #1 spark plug wire, into the #1 spark plug, through the engine block, reverse firing to #5 spark plug then into the #5 spark plug wire back to the coil. That's one of the reasons Ford specc'd double platinum plugs for some of these motors. One bank fires from the center electrode tip to the ground and the other bank does the opposite. This causes different wear patterns on the plugs. Double platinum prevents odd wearing that would occur in single platinum plugs.

ANYWAY, if one side of the engine is 'running' then the coil pack, wires & plugs should be perfectly fine. As far as I know, the only difference between the engine sides is the injectors. You have a 93? I'm not sure if those are sequential or batch fire. If they're batch fire, the injectors on each side of the engine fire all at the same time. You could just have a fuel injector harness/plug issue.


*EDIT*
Saw your new post. I'd double-check #3 & 4. 2 & 6 not causing a change makes sense, could be a wire or plug on either one causing both to die. Run a test on your coil pack just in case:
CoilPackTest.gif

Then check your plug wires for resistance, you should be near or under 10k ohms on all (my heavily used ones ranged from 4-10, they should be less).

Course, I could be barking up the wrong tree but it's good to get thoughts flowing.
 






Swapped plugs and opened gap to .054. No change. Bit the bullet and pulled a wire at a time. 1, 4, & 5 made the idle change. 2, 3, & 6 no change. All six arced.
 






The thing is, spark plugs HAVE to fire in pairs or they don't fire at all.

Take a look at this:
FiringOrder6a.gif


*edit* whoops, not done posting :D

That's the same pic as in my manual and I checked em while I was swapping plugs.
 






Swapped plugs and opened gap to .054. No change. Bit the bullet and pulled a wire at a time. 1, 4, & 5 made the idle change. 2, 3, & 6 no change.

I would say get some new plugs..arc just means the coils and wires are good....you can get cheap ass NGK TR55 plugs for like $6..thats the plug I run in my stock motor and "think"I gap to .055
 






That's the same pic as in my manual and I checked em while I was swapping plugs.

Check my post above, I edited it. I'm talking more about firing order and how the coil pack works.

*EDIT*
Also, what jd4242 said got me thinking... if the plugs are wet from not firing, that will further cause you headaches. Replace the plugs for ***** and giggles but let the cylinders dry out. Leave the plugs out for a while and maybe turn it over a couple times just for good measure.
 






Her current rig is a '93, the one I'm working on is a '92. Not that it matters, but the engine in the '93 uses '92 belts and pulleys...does that make it a '92 engine? I mean, if there is that kind of difference between '92 and '93 (batch vs seq), not sure if I can actually pull injection/ignition/fuel parts from the '93 to test the '92........
 












Check my post above, I edited it. I'm talking more about firing order and how the coil pack works.

*EDIT*
Also, what jd4242 said got me thinking... if the plugs are wet from not firing, that will further cause you headaches. Replace the plugs for ***** and giggles but let the cylinders dry out. Leave the plugs out for a while and maybe turn it over a couple times just for good measure.

Funny you said that. I wanna say a couple of the plugs seemed a bit wet and smelled of fuel, but not soaked.

How do I kill the fuel pump so the injectors don't squirt when I spin this over to evac the cylinders? I'm at my $0 point, but I can pull the plugs from the '93. I'm gonna go pull the plugs now so she can dry out over night.

I'm so mad that this thing runs like this. Murphy is a dick. This rig ran SSSOOOOO nice before I did the heads....just makes this whole issue piss me off even more...I'm not giving up, not by a long shot. Everything is telling me it's something stupid.
 






Funny you said that. I wanna say a couple of the plugs seemed a bit wet and smelled of fuel, but not soaked.

How do I kill the fuel pump so the injectors don't squirt when I spin this over to evac the cylinders? I'm at my $0 point, but I can pull the plugs from the '93. I'm gonna go pull the plugs now so she can dry out over night.

If you pull the plugs with the motor still warm the cylinder will pretty much be dry by time you reinstall them ;)
 






True, but it's dark here and I'm under a carport. I'm done for tonight. But I know where I'm starting tomorrow after work. Thanks for all the input guys. Please, keep it coming.

Oh yeah. While draining the oil, I saw something funky with the calipers, so no test drive till I look at that.

I'm really glad you guys are thinking ignition....that one push-rod gives me nightmares....
 






Don't give up MindBender. You can spin the engine over by shorting the small post on the solenoid (remove the capped wire first) with the post that's furthest forward. This will kick the starter on but the computer and everything else will be off. This is where you would hook a remote start switch.

If the engine is still warm, follow jd4242's advice.

I had similar issues when I swapped out injectors on mine. Ran like crap, shaked, almost died when put into gear. A few cylinders weren't firing. All I could figure was that a couple of the injectors I put in were either frozen closed or leaking or dirty or something. Popped the old ones back in and all was great. It very well could be just a harness issue. Did all the injector plugs snap in fully? Do you have a stethoscope so you can hear them clicking?

Did you ever check your compression after installing heads? I hate to sound like a pessimist but maybe there isn't enough compression in a cylinder or two. If all is well there then it has to be spark or fuel, both of which are simple systems in these first gens.


*EDIT*
Which pushrod was it? It's possible that if a valve isn't opening, that could kill a cylinder and with excessive fuel in that cylinder, sparking is more difficult and it could kill it's twin cylinder on the coil pack, leaving you with 4. I doubt that though. Excessive gap in the valvetrain is just annoyingly noisy, not detrimental is most cases.
 






Don't give up MindBender. You can spin the engine over by shorting the small post on the solenoid (remove the capped wire first) with the post that's furthest forward. This will kick the starter on but the computer and everything else will be off. This is where you would hook a remote start switch.

If the engine is still warm, follow jd4242's advice.

I had similar issues when I swapped out injectors on mine. Ran like crap, shaked, almost died when put into gear. A few cylinders weren't firing. All I could figure was that a couple of the injectors I put in were either frozen closed or leaking or dirty or something. Popped the old ones back in and all was great. It very well could be just a harness issue. Did all the injector plugs snap in fully? Do you have a stethoscope so you can hear them clicking?

Did you ever check your compression after installing heads? I hate to sound like a pessimist but maybe there isn't enough compression in a cylinder or two. If all is well there then it has to be spark or fuel, both of which are simple systems in these first gens.


*EDIT*
Which pushrod was it? It's possible that if a valve isn't opening, that could kill a cylinder and with excessive fuel in that cylinder, sparking is more difficult and it could kill it's twin cylinder on the coil pack, leaving you with 4. I doubt that though. Excessive gap in the valvetrain is just annoyingly noisy, not detrimental is most cases.

Thanks for the solenoid trick!!!

My wife isn't going anywhere tomorrow, so I KNOW those ones will be dry and good. I'm not even gonna mess with the gap.

As for the injectors, before I even started to swap o-rings, I did an ohm test on all six (had to do the same check on the '93 last winter). All six checked out good. As for the injector plugs...one clip on every plug is broke off, sssoooo....nothing felt like it went together 'loose'.

The lifter in question is intake cyl #3 . With your theory, that should also kill #4 . #4 is live. Wait...INTAKE on #3 . IF that push-rod had issues, their'd be NO fuel in that cyl and #4 live. If that push-rod had issues preventing the intake valve from opening, well, I definitely wouldn't be running the RPM's to 2K, so we can THANKFULLY rule out valve-train. Annoyingly noisy agreed!!! I love the knowledge in here!!!

As for compression, I can't do the test (no $ for tools, but it's on my list!!!). Only going off the look of the cylinders, tiny ridge, cross hatch...how well it ran three weeks ago...either a catastrophic ring or head gasket failure in three cylinders at the same time....at this point, I'm hoping the odds are in my favor....

Please don't take anything I type wrong. I think as I type.

I'm at the point that if I knew 100% that I could pull all the parts I'd need off the '93 to make this work, I will.

Hell....for that matter, if you guys were in my place and have access to a running '93, in interest of getting to end result sooner.....open table....
 






You can't really rule out injectors based on an ohm test. The ones I put in passed the ohm test just fine. The test is just for the coil internally. Just because the coil works, doesn't mean the pintle is actually moving and even if the pintle is moving, doesn't mean that fuel flow isn't clogged/impeded.

However, it ran fine before so I would kind of doubt the injectors are bad. Then again, how long did they sit without fuel? I don't know how long it would take but they might have dried up inside and become stuck. Again, I doubt it but... I know many injector rebuild shops rebuild them when you order them and state that you have to install them within a few days or risk them sticking/drying up. They do oil them but that only lasts so long.

In my opinion, ignore injectors until you've ruled everything else out.

Try swapping the plugs around again and then pull the wires to see which ones don't affect idle. If it's the same ones then maybe it is time to think about injectors, either the connection or the whole unit.
 






Haven't swapped plugs yet. Fired up the 92 and pulled wires. 1, 2, 3, &4 are dead. It's running on two cylinders. Now I'm gonna pull the ones outta the 93. Wires too.


Plugs 1-4 wet. 5 & 6 burning. That tells me at least all 6 injectors are letting fuel in...
 






Wires and plugs swapped. New wires all measured 2.0k other than the longest two. They were 2.5 and 3.0. Still runs the same. Swapping coil. Just for giggles, I pulled the vacuum line off the fuel pressure regulator and nothing changed....normal?
 






This was SUPPOSED to be a simple effing head job. Murphy can blow me. Coil, wires, and plugs swapped. Still runs like crap. This time when I pulled wires, nothing made any REAL change. If any, just for a second and that was only when I put the wire back on. So, I'm thinking either my injectors are stuck open, or the pressure reg is letting too much through. If I'd have dorfed something up with the heads/valves/push rods, I'd hear it somehow wouldn't I??? I mean for cripes sake, this thing 'seems' like it's running on two cylinders!!! I now know, for a fact, the wires are in the right order. I pulled one at a time (wire and plug) from the '93, checked resitance of each wire, and put them in the '92. One...by...one. She took the '93 grocery shopping yesterday which entails 1.5 hours at freeway speeds. If it was running like this, she wouldn't have left the driveway, so I know the wires/plugs/coil are good.
 






Check vacuum lines then..have you scoped the injectors to make sure they are all opening and closing.
 






Check vacuum lines then..have you scoped the injectors to make sure they are all opening and closing.

When I pull vacuum lines, it runs better, but still like crap. I don't have a stethoscope to listen to the injectors. The LIM did sit out in the open air for about three weeks while waiting for parts. I still have one LIM gasket left...might just swap injectors. The ones in the '93 were replaced not even a year ago...

What you think about what I said about pulling the vacuum line off the reg with no change?
 



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When I pull vacuum lines, it runs better, but still like crap. I don't have a stethoscope to listen to the injectors. The LIM did sit out in the open air for about three weeks while waiting for parts. I still have one LIM gasket left...might just swap injectors. The ones in the '93 were replaced not even a year ago...

Use a long extension or screwdriver or piece of wood..spare nipples are capped on the vacuum tree? Vacuum line on the tb??

Last check..look at the wiring on the injectors all on one side.each should have a independent hot wire BUT all the grounds should connect all on one side(batch fire)..its possible the wiring harness is from a cali model, which could be SEFI..but if so it should have had a cam sensor and egr..also I believe regular 93 do have a cam sensor but not SEFI or egr..your 92 should have batch but no cam sensor, the wiring for the injectors ""should"" be same for regular 93 and 92.

Hope any of that makes sense
 






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