Firing order off-misfire-and much, much more!

Birddog85

Registered User
Well, here we go..
I picked up an 89 SC last weekend and it's not quite right (much like myself).
The drive home was really fun, all types of smoke followed me, it was so bad at one point that a School Bus had to stop till it cleared..:eek:
Turns out the dipstick tube had come dislodged and oil was spewing all over the place.

The other issues are a heavy misfire at idle and under load, no cel, my firing order seems to have changed and she is running pig rich.

Firing order first. My searches say it should be as follows.
1-2-3
4-6-5
The only way I can get it to run is.
1-2-3
5-6-4
And it misses like crazy under load, idles like a Pro Stock and the exhaust is so rich you can't stand behind the car. Oddly in neutral it'll rev like mad but it will shroud you in a fog of fuel.

I've pulled the Cam sensor plug with no change. Ive pulled the spout with a slight idle change.
I had the DIS tested at 3 different Parts stores, two stores passed it and one failed it which is odd.

A compression test, plugs and wires will be a project for this coming weekend.
What's bugging me is the firing order.

(The car does have a few mods that I didn't know about until I dug in. I've found aftermarket exhaust with high flow cats and DynoMax turbo mufflers, overdrive pulleys, a BBK/Eddy 70mm throttle body and the MAF body looks to be aftermarket as well. I haven't checked the ECM yet.)

Yes I did buy this a little hastily. Here in the Midwest it's a bit rare to find these with their sheet metal intact at a reasonable price.

I'll stop rambling now.

EDIT: There is quite a bit of "blow by" on the mill. At idle you can see a quick chug from the dipstick tube. Im starting to think Detonation has taken its toll.
 
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Some of the third party repair manuals have it wrong.

This is the correct order:
PlugandWireLayout.jpg


Have you run the codes yet?

Know how to check fuel pressure?

Checked for vacuum leaks?
 
123564 is correct then passenger side 123 driver 456 front to back misfire and stumble under load mostly bad wires be exposed or loose on plug. As far as rich either coil or o2 could be bad especially if they have over 100k or had antifreeze pass by them.
 
Some of the third party repair manuals have it wrong.

This is the correct order:
PlugandWireLayout.jpg


Have you run the codes yet?

Know how to check fuel pressure?

Checked for vacuum leaks?


Crap, the firing is right. I haven't checked for vac leaks yet. She can pull 20" at about 1000 rpm, at shaky idle it's 10".

I'm starting to think Detonation has popped a piston.
 
Some of the third party repair manuals have it wrong.

This is the correct order:
PlugandWireLayout.jpg


Have you run the codes yet?

Know how to check fuel pressure?

Checked for vacuum leaks?


I haven't gone for Vacuum leaks yet. I do have blow by issues. I'm thinking a compression/leak down test should be in order.
 
If blowby blew out the dipstick, yes, I'd be interested in what a compression test showed.

I guess you already checked for water in the oil - good luck and keep us posted.
 
If blowby blew out the dipstick, yes, I'd be interested in what a compression test showed.

I guess you already checked for water in the oil - good luck and keep us posted.

Yes, no oil in the water and vise-verse. The guy I got her from was pretty clueless. I'm thinking he filled up with 87 and ratatatated her to death.
 
Do plugs and wires. Even if they seem OK, it is amazing on these cars the strange and unpleasant things a bad wire or plug will cause. Next is the vacume leaks, same as above, and as has been stressed on the site MANY times, a smoke test is really the only way to go here, the spray it with "stuff" and listen for the change in RPM won't work on these rigs. The comp reacts to "fix" it too fast to hear unless it is a MASSIVE leak

Adam
 
Live close to davenport. I have some manuals and some extra parts let me know maybe l could help.
 
I think you are right to cover the basics with compression and leak down tests. While you are there check the wires and plugs thoroughly. Bad plugs and wire will really make these things run badly. I have grown to also like my infrared thermometer. A cool exhaust port will ID a weak cylinder right now especially if it is ignition related.
 
Live close to davenport. I have some manuals and some extra parts let me know maybe l could help.

Right on! Someone local.
This car has been for sale in the area at least 3 times before. Maybe you've seen it. I think the PO got her from someone near Byron.
 
I think you are right to cover the basics with compression and leak down tests. While you are there check the wires and plugs thoroughly. Bad plugs and wire will really make these things run badly. I have grown to also like my infrared thermometer. A cool exhaust port will ID a weak cylinder right now especially if it is ignition related.

I'm going one step at a time. The blow by concerns me a bit but she should run better than this. The plug wires are broken down cheapies but someone spent money on Motocraft Platinum?

If it were any other car It'd have been stripped and scrapped (The PO was close to doing that too).
She's just so damn good looking.
 
I have some software we can put on an 89 and see what's going on. I am over near Des Moines, but a weekend trip isnt likely as it's harvest season. Any chance you can trailer it over here? More then happy to help, just swamped with work right now.

Personally until it's figured out I would go back to a stock MAF, TB and everything else just to make sure a tune isn't needed. I have several Mafs and TBs that are stock for the 89 you are more then welcome to use them just ask for them back when you are done. If you dont have it fixed by March I will be able to help.
 
I have some software we can put on an 89 and see what's going on. I am over near Des Moines, but a weekend trip isnt likely as it's harvest season. Any chance you can trailer it over here? More then happy to help, just swamped with work right now.

Personally until it's figured out I would go back to a stock MAF, TB and everything else just to make sure a tune isn't needed. I have several Mafs and TBs that are stock for the 89 you are more then welcome to use them just ask for them back when you are done. If you dont have it fixed by March I will be able to help.

That's above and beyond! Thanks!
Like I posted in the other thread, I think I'm looking at an injector issue.
I've been wrong before though.
 
I'm laying off the injectors. Once the rail was up I found no leakage with the system pressurized.

I'm also finding that everything I touch has been touched before.
Every bolt ive pulled (including the fuel rail bolts) has had anti seize on them. The EGR delete and Teflon charge pipe seals should have been a tip off.
Tomorrow mostly everything goes back together with new plugs and wires.
Start from the beginning.

One problem, the P.O. cranked hard on the collet for the upper charge pipe and split it..
 
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