Hi, been a longtime ford truck lover but just recently got an Expedition. Its a 1997 and we have been driving it for several months. It has had the check engine light on for quite awhile with no signs of a real problem till yesterday. We were coming home and it started shaking and running really rough almost like the transmission was slipping too, but I was still able to accelerate, the check engine light started flashing... it did this for quite aways but before I got home (I was an hour away from home when it started) it stopped running rough and the check engine light stopped blinking and went back to being on permenantly. Any ideas of what is going on? Would love to fix myself but don't want to drive it until I have an idea of what I am dealing with. Thanks for any help!

 

Helloooooooooooo!!!! The CEL being on is a sign of a 'real' problem.

A flashing CEL means one or more of the cylinders is misfiring enough to damage your catalytic converters. Since you drove an hour that way, you might end up replacing all of the catalytic converters in addition to fixing the misfires. Oh and you might want to get the codes read. The CEL being on might have been the PCM trying to warn you of the impending misfire issue along with which cylinder(s) the problem is at.

 

So I am guessing I shouldn't drive much further on it? Do you have an idea of what that will cost to replace the catalytic converters? I appreciate the help very much. Trying to save money as much as possible so it is nice to have an idea of what is wrong.

 

It's about $800 to replace all of the CCs. As far as driving it goes, if the CEL isn't flashing you can chance it, but if it's flashing I wouldn't drive it.

 

I had this happen to me after a tune up on mine. Check to see if one of the plug wires is not snapped down on the coil. That fixed my problem

 

I know this is a old post but I'm having this problem also, I've got a code for a bad EGR valve, could this be the culprit also??????????? Any new info would be greatly appreciated.

HalfBreed

 

A bad EGR will cause stalling, lack of power, and rough idling. It doesn't really cause misfires. You could have a misfire and an EGR issue.

 

Yeah, take your CEL seriously. A flashing one is an indication that you should not drive it until it's fixed. I took a chance with it, and I damaged one of my two CCs. If I lived in a country where it would fail emissions then it would cost a serious amount to get it fixed, but here nobody cares if you decat so I might be doing that with a stainless exhaust, though I am thinking of designing it so I can drop in a CC on each side in the future, and just run a "test pipe" for now.

 

I have a 2006 navigator and I was half way to work about 40min out n the touch started running rough. So I pull to the side of the road to access the situation n I noticed the CEL on. It went off n I drove to work the light has not come back on nor is it running rough. But when I sit with the truck on in park it shims a little. Don't have much money but I don't want this to become a bigger issue can someone Please HELP??!!

 

You have a misfire. The next time the CEL comes on don't turn it off until it's been scanned for codes. Autozone will scan it for free. The code will tell you which cylinder is the problem. Once you know which cylinder we can help you diagnose it further.

 

2006 Ford E250 Cargo Van. I have had similar problems to above. My CEL light came on and started to run roughly so I took it to get a tune up which read for faults for- PO302, PO316.
They gave me some Foam Soap to put in my gas to clean the fuel tank and the light was turned off and it was running fine.
2000km later (driving to Alaska) the light started to flash and the car was shaking but we were in the middle of no where so had to continue to the next town (for aroind 2 hours). The light eventually stopped flashing and stayed on permanently (occasionally turning off).
We are wanting to fix this cheaply and as soon as possible as we still need to travel all the way back down to Canada.

Please HELP !!

 

Sounds like a misfire. The only way to know which cylinder is to have it scanned and get the code(s). Many auto parts stores will scan it for free, but leave it running when you get there until it's scanned because some information can go away when the key is turned off.

 

it should save those codes as history codes... if the CEL is flashing yes shut it off!!!! the best way to catch the misfire is to do a diagnostic with the scan tool connected and looking at the misfire counts from each cylinder