So for the past couple of weeks, I noticed my truck would sputter and break up a little when you give it heavy throttle. At first, I thought it was my Magnaflow 16616, but I had it checked for leaks...and that wasn't it. SOOOOOO....I take it to the dealer this morning to have it looked at. The service director goes for a ride with me and STARTS to give me the "its normal or it may be the exhaust" Then he and tech go out and they hooked it up to some computer through the OBD port and there was a slight miss in cylinder #2. You could see the line on the screen point down while the other lines stayed pretty straight. They swapped the coil....that didn't fix it, so they said they were gonna swap the spark plug After reading all of the horror stories about the plugs in these things....guess what happened! The plug broke in the head. The service guy say its down for the count for today probably. So I'm rockin' an Escape until its fixed!

What do you guys think would cause a miss/hesitation under heavy throttle? It doesn't do it until its warmed up, but when its warmed up its noticeable. Then only thing done to the truck is exhaust.

 

Fuel filter possibly?

 

Not saying it couldn't be, but I seriosly doubt it's the plug. I can't believe they broke it. Not too sure about your dealer. How many miles on it and how long since a fuel filter change?

 

I have almost 32K on it.
I don't think its the fuel filter because they hooked it up a computer where you can see EVERYTHING diagnostically while its running. You could see #2 start to spike down when you give it gas. If the fuel filter was bad why would #2 just drop?

 

I don't know. But if they broke off a plug, I doubt they know either. Has the filter ever been changed? If it hasn't, I guarantee you it needs it.

 

Maybe an injector is partially clogged.

 

Look something like this:



If it's an early build 2006, I'd suspect injectors before anything else.

 

My thoughts exactly. - Og

 

I dont think it would be the filter unless you run junk gas all the time. my buddy just changed his for the first time and its an 04 and it was running just fine before the change.

 

He was lucky. There have been cases on here where they were clogged at 20,000. You should see what comes out of some of them at 30,000 miles or so.

 

I think Quintin hit the nail.

FWIW, I still haven't changed my fuel filter, and I've never changed a fuel filter prior to 100,000 km's. I have a new Ford fuel filter sitting in my garage too. The truck has 72k km's on it now. No sense in wasting money on parts when the one's still in operation are fine. The filters I have changed at 100k still looked fine as well.

 

Like that....
When it was at idle, the lines were pretty straight. When he reved the motor, they went up, but #2 looked spiked down while the others went up. I called them and asked them about the fuel filter and they said that they are gonna get the plug out....put in a new one and see if that is it. If it isn't, they are going to injectors and fuel related possibilities. He said they'll probably change the fuel filter 1st if the spark plug isn't the problem.

....we will see!

 

They got the plug out...put a new one in and that wasn't it. Now they are moving on to the injectors/fuel system.

If thats not it...WTF could it be?

 

I'd bet it is the injector

 

On my Pontiac Grand Prix my misfire was caused by a partially clogged injector with the same symptoms you are complaining of. They ran a fuel system cleaner directly into the fuel line and never had a problem again.