Engine Stuttering / Acceleration Vibration

[Snapshot]

Hello guys, I'm having some issues with my Expedition. I have a 2000 Expedition XLT 5.4L V8 with about 153,000 miles on it. Starting today, it has started to have some very noticeable vibration. This vibration occurs whenever it idles or whenever I accelerate. It started about 30 minutes of driving today; I got some gas and drove to another city to pick something up. When I was driving up a hill on my way back, the service engine soon light started flashing; there was no sound that accompanied this nor was there anything that I had ran over. Once I got off of the exit, I noticed the vehicle was vibrating and I could hear a stuttering. I got home and turned the vehicle off and back on and the light went off and stayed off but the stuttering and vibration is still there when it is driven.

I have tried a few things already. I tried some fuel treatment in-case to see if I had bad gas, but it did not make any difference. I unplugged the mass air flow sensor to see if there would be any change while the vehicle was on and there was a slight improvement, but it's not enough to stop it. I have noticed that area around the front of the vehicle smells odd whenever the engine is running and whenever I drive at faster speeds and higher RPM, there is this burning smell. I also noticed that when I let off of the accelerator, the vibration stops whenever the vehicle is moving and when idling, pressing the accelerator calms the stuttering sound. Whenever I accelerate from a stop, it vibrates like something god awful. As a whole, it will smooth out some whenever I travel at speeds 30+, but it is still there.

Other than that, there is nothing remarkable to tell. I have been having some issues with what sounds like the exhaust rattling from underneath the vehicle and I have noticed the system as a whole vibrating a lot whenever the vehicle is stopped and running. I have been driving around some to try to get that engine light to come on so my mechanic can run diagnostics, but there has been no luck there

Any help will be greatly appreciated, I hope I can make this vehicle last until February when I will be buying a newer Expedition!

 

[stamp11127]

Take it up to Advanced or Autozone and ask them to read the codes. You should have some stored in memory, might get lucky and have active codes when you get there.

When was the last time it had a tuneup?

Unless it is a rust bucket, at 150,000+ miles it still should have some life left in it. I don't buy cars/trucks unless they have at least 100,000 miles on them.

 

[Go4Life]

Mine was shuttering and vibrating as I drove it. It did it most when I was around 40 MPH or 1500 RPM. I changed the Coil Packs on it and it now runs nice and smooth. That's my experience, but try to get the codes checked and see what it is exactly.

 

[1997SCEBFEX]

plugs, coil-pack(s), ...general tune up as mentioned above.
can't go forward without the codes.

PanHandler.

 

[Snapshot]

Good news guys, the service engine light has popped back up on the dash. My mechanic doesn't open for another 3 hours, so it'll have to wait until then. Fortunately, his shop will run any diagnostics free since I've been with them for several years. I had a tune-up when I hit the 150,000 mark, which was about a month ago. I'll keep you guys posted on what I have

Edit: I took the vehicle to Advance and someone there ran their scan tool. The diagnostics said that the engine light came from the MAF sensor, disconnecting the battery removed the code for it. The guy who checked it said that it has a dead miss in the engine. My normal mechanic is still not in yet, but his scan tool is much more powerful than what they used; is should be able to count the misfires if that's actually what the issue is. Other than that, I'm shooting in the dark.

 

[metaldrgn]

The flashing light means there is a potential for engine damage if you keep driving it that way. I've had a misfire without codes for a bad connection on the cop #4. Had to change it out and splice in a new connector. It had the infamous coolant leak. Don't know if your year is effected by it too. If you are getting a maf fault make sure the connections are good. Was that the only fault?

 

[Snapshot]

I got the issue you fixed, I finally got the light to come on with what was wrong. The MAF was caused by me tinkering around to figure out what was wrong before the real code was thrown. It was a cylinder 6 misfire and turned out to be a bad cop. It took two days of driving to get the engine light to kick on to get a scan done.

After I fixed that issue, I noticed some occasional stuttering and the engine light popped on again. I got it checked and I had a P0401 code that was thrown. I looked at my DPFE hoses and they had dry-rotted and broken so I replaced them. I don't have anymore stuttering, but the light is still on before I start the vehicle (which it has never shown up before) and goes off once I start the vehicle. I unplugged the wires running to the sensor with the vehicle running to see if it would throw the code with engine running and nothing happened. I think I'm going to replace the DPFE, but I'm not sure yet.

 

[metaldrgn]

The check engine light is supposed to come on before you start the vehicle and goes out after it's started if everything is working right...

 

[hannibal]

I have the same problem, but when I went to the shop they told me my cylinder 6 was at 75% that's why I was misfiring should I get a second opinion? my codes were po303,po306 po171,74 Then he said I needed a new engine

 

[bedrck46]

303 is cyl 3 misfire 306 is cyl 6 misfire 171 is bank 1 to lean 174 is bank 2 to lean Take care of the misfire problem new plugs and or COP or both. also could be the connector between the cop and plug fixing the misfiring problem may solve the lean conditions. do you have the 5.4 or 4.6 engine