2000 V10 Ex 135k and this problem is getting slightly worse. When idling it's very smooth and only standing outside hood up and on the passenger side listening to engine and exhaust is this faint popping sound. On easy acceleration can feel the intermittent popping until easing up on the throttle. Though maybe bad gas but using same high volume gas station. I have been using regular gas for sometime with no problems till now, I tried an octain booster with no change. Any suggestions please.

 

You may have an exhaust leak. Check for missing bolts on the manifold.

You may also want to check if all your spark plugs are torqued properly before you run it again just in case you have a loose plug.

 

Funny you should mention exhaust bolts, I had 4 broken off on the drivers side and just had them replaced, a three day job. I checked the spark plugs and all nice and tight. Thanks...

 

I know this is an older post but you could also check for carbon build up in your throttle body. It can cause the butterfly to snag some.

 

Hi, Thanks, Do you mean the butterfly sticks? It's more of a problem under constant slow acceleration, it just misses. I'm thinking that it might be one of those high voltage modules that sit on top of the plugs, I heard they can be a problem. I suppose a question is; if I took the vehicle to the dealer will their computer be able to tell which modules are at fault? I took the Ex to Auto Zone and they wouldn't look at it due yo no fault light showing. Thanks very much for this...

 

You mean the coils? (COPs)

 

Go buy your own code scanner, they are priceless.

 

You've had this problem for almost a year and a half and haven't fixed it yet.

Sounds like you have a bad coil. Get it scanned and see what codes you have.

 

Well, thank you Jay ....coil (COP) sorry.

As far as buy my own scanner, two other shops put there scanners on even with having no trouble light and didn't show a fault. I had asked if the dealers scanner would show the individual cylinders, I'm sure they have something more elaborate than a hand scanner but the minute they hook it up your paying the big bucks. Phoning them, they just want the vehicle then your checkbook.

Has it been a year and a half ......it doesn't hesitate all the time, mostly driving the vet over the summer. Gotta be a COP and it would be so nice to know which one before I start climbing around this huge engine.

Many thanks.

 

Just out of curiosity, maybe your rubber boots for the plugs have a crack and causing a misfire. Change them all out and see. They're only about $5 a piece.

 

Unplug one at a time. If you unplug a good one, the truck will obviously run worse... if you unplug the bad one it shouldn't change much. Although you said it idles smoothly so I don't know if that'll work. A decent scanner should tell you though...

 

I'm thinking probably a coil too, but I'd check your plugs and replace them if necessary, as well as clean up the intake. Probably can't hurt to get some mass air flow sensor cleaner and give that a good spray down. Probably couldn't hurt to take the whole intake tube off and make sure the butterfly valve is clean too.

 

You can't unplug one at a time to tell but you can sure replace one and drive it to see if that fixed it. If it still does it, just swap that good coil to the next cylinder. I did this when mine had the same symptoms and got lucky and replaced the bad coil first try!

 

I found the bad one on my dad's Focus and the 2 bad ones on my old Crown Vic using that method... probably isn't the best way though...

 

Thanks guys, good advice. Think I'm going to buy a set of rubber boots and the goop that goes with it and a COP and probably start changing one, driving it and going to the next one. It's a bear of an engine to work on so it's going to be a work in progress. Watch it will be the last one...... I've removed and cleaned the air flow sensor so that's off my list. I still really haven't been told if the dealer has a scanner that will point to the faulty plug, it doesn't show an engine fault light so most say the scanner wont show anything, is this correct? Many thanks to you all for your input ....Dave