miss

veritas · 12-30-2007, 11:14 AM

I have a 1997 ford expedition just got it.

the truck has 240,000 miles.

My check engine light came on and the code showed a miss in the third cylinder.

I checked the coil pack with some type of tool where you lay a flipper on the pack and if a red and green light dont light up the pack is bad.

The pack read bad. I replaced it with one from autozone duralast I believe.

Then the truck ran great again. Another day later and the truck is running foul. When at idle the truck seems to miss and then when the truck is near shift around 30 mph I would guess the truck starts to miss and stutter. It is almost identical to the problem as it started before I replaced the pack. I imagine I should have replaced the plug as well. But I didn't

Where to go now? The engine light isnt back on yet. I

Thanks for any information.

jonmark1985 · 12-30-2007, 11:58 AM

Im with you 100%, pull the plug.

veritas · 01-01-2008, 01:20 PM

Well check engine light never came on but hooked up snap on diagnostic to find a miss in the second cylinder...

I am going to do a complete tune up.

so heres what I am planning.

plugs.

maybe new sleeves for the coils? Can you get these separate is it a good idea?

PCV valve.

Fuel filter.

Anything else I should consider on my tune up?

kailor · 01-15-2008, 09:26 AM

It's good to always begin troubleshooting a "miss" by checking the vacuum lines.

veritas · 01-16-2008, 01:07 PM

thanks will do!

TBIRD430 · 01-22-2008, 02:41 PM

I would check the large vaccum hose from the PVC valve for leaks as well. I also recommend running 2 cans of Sea Foam brand fuel treatment through ur SUV. 1 can in the gas tank and 1 can sucked through the power brake booster line (with truck running). Do this outside b/c there will be a SMOKE show and a foul oder from ur tailpipe!!!

veritas · 01-25-2008, 07:54 AM

I have heard a lot about sea foam I think its time I tried it.

Whats the best system for checking these vacum lines? I was told by a friend I could spray some carb cleaner in the engine compartment and see if I got a response out of the motor indicating a vacum leak other than that he said I would have to get a hold of someone with a system to put some thing into the the vacum lines and visualy look for a leak. I have no experience with vacum lines and leaks.

Thanks again for all the info when I will try all these thing for now Im rolling in my Lincoln.

TBIRD430 · 01-25-2008, 10:34 AM

Usually with the truck running, u can move the PCV vaccum line around and know pretty quickly if u have a leak there (usually the elbow ends). Other than that line, there are only a few more that I know of to check. On our 1999 4.6L there is a vaccum connector coming out of the right side of the upper intake manifold, which splices out into 3 more vaccum lines. These 3 lines run to the EGR valve, fuel pressure regulator, DPFE senor, EGR purge solenoid, and some switch/object by the power brake booster (on the left firewall). I think spraying the carb cleaner around CAREFULLY on a cold engine is a good way to check these vacum lines. And u can always go back with regular vaccum hose if u need to replace any of those damaged OE plastic vaccum lines/tubes....

Keep us posted bro.

veritas · 02-05-2008, 12:45 PM

Well did the easy part and added the seafoam through the brake booster line it made a lot of smoke and seems that the truck runs a little smoother but still the miss.. I'm just waiting for a friend to get me some garage time since I live in WI its way to cold to be messing around outside. I looked at the pvc line and it seems to be fine I will check it closer once indoors. Thanks again for the advice and I will let you know as things progress!

TBIRD430 · 02-06-2008, 09:46 AM

Sounds good. U did drive the SUV after the smoke show correct?