Engine Sputtering

[BigDave!!!]

On the way home from an off road trip in the desert i noticed my car sputtering while acceleration and a also a little bit while cruising, i got home and took apart the intake to clean out the filter and noticed a small amount of dust that coated the inside of the intake. i cleaned it out and thought that was the problem but apparently it isnt.

ive done a search and cant find anything conclusive but the symptoms are that it sputters and surges when accellerating and when it is in idle i can hear a popping noise every couple seconds from the muffler. when i rev up the engine in idle it is fine only when i am driving it sputters. any ideas as to what it could be?

 

[boominXplorer]

fuel filter, egr valve or maf would be my guess.

 

[BigDave!!!]

i was thinking along those same lines but didnt know why those would cause that poping noise in the exhaust

 

[boominXplorer]

its a misfire thats why

 

[section525]

Check all your wire connections. Maybe something came loose during this:

 

[Katmandu]

ive done a search and cant find anything conclusive but the symptoms are that it sputters and surges when accellerating and when it is in idle i can hear a popping noise every couple seconds from the muffler. when i rev up the engine in idle it is fine only when i am driving it sputters. any ideas as to what it could be?

Mine just started doing the SAME damn thing.

Mine started right after I ran Seafoam through it strangley enough ??

My MPG has dropped 6-7 MPGs.

NO CEL or anything obvious like loose connections etc... The plugs are fairly new as well.

Anyone have more suggestions for Big Dave and myself ??

 

[dogfriend]

its a misfire thats why

I think he may be right. Check your plugs and plug wires. Also test the resistance of the coils in the coil pack. I had to replace my coil pack because it would miss every once in a while at freeway speed, especially going uphill.

 

[96limitedX]

check that MAF caused the same problems in my moms '94..caused alot more work because we never thought it could be the prob.

 

[BigDave!!!]

yeah i think you guys are right with the misfire, ill check everything in the morning. thanks guys and if you have any more suggestions keep em coming

 

[Katmandu]

yeah i think you guys are right with the misfire, ill check everything in the morning. thanks guys and if you have any more suggestions keep em coming

Mine is definately a misfire.

Aldive suggests getting an OBD-II Scanner on it. (**NOTE** Not a OBD-II "reader"). A scanner will read the MIL and sensors during real time. Now I need find someone who can do this CHEAP!

BTW, my EX is missing/stumbling at idle and below 1500 RPMs. It runs like a raped ape at WOT!

What would cause a low RPM misfire ??

 

[dogfriend]

What would cause a low RPM misfire ??

A vacuum leak. Because it causes the mixture to go lean, which makes it harder to fire.

At WOT, the vacuum leak will have little effect because the vacuum is low anyway.

 

[BigDave!!!]

yep you guys were right with the misfire, i plugged my new obd reader into it and pulled PO301, or a misfire in cylinder one. didnt have time tonight but i plan on checking the coil, plug and wires for any defects. looks like you nailed it on this one dogfriend. Anything else i should check while im at it that would cause this problem?

 

[BigDave!!!]

figured i would post an update for anyone else who might have symptoms like this. Went by pep boys and picked up a new set of 8mm plug wires and a replacement platinum plug.
pulled out the old plug and it actually looked pretty good, just a small amount of glazing. then swapped out the old plug wire with the new one and disconected the battery. took it for a drive for a few mins and no check engine light and no misfire. I guess since i bought a whole new set of borg warner 8mm performance wires ill wire up the rest. anyway, theres the update and i hope this might help someone out in the future

 

[Katmandu]

yep you guys were right with the misfire, i plugged my new obd reader into it and pulled PO301, or a misfire in cylinder one.

My Ex didn't throw ANY codes.

I'm still searching for a vacuum leak somewhere ??

Anyone have tips to trace vacuum leaks ??

 

[dogfriend]

Anyone have tips to trace vacuum leaks ??

An old trick is to get a propane torch (e.g. Benz-o-matic). DON'T LIGHT IT! Turn it on and pass the UNLIT nozzle around the areas where you suspect a vacuum leak while the engine is idling. If the propane is sucked into the intake manifold, it will raise the idle speed momentarily.

 

[Packin]

Engine Sputter

I went on a road trip this past weekend and noticed something going on with my 2001 Limited 5.0L V8. It happens when I'm cruising along highway speeds about 70, low rpm's and when I start to go uphill the engine somewhat sputters and kind of jerks you a little bit. If I increase acceleration it clears it up and doesn't do it, but as soon as I go back to low rpm's it will do it again.

The truck has 125k miles, runs fine all other times and the check engine light is NOT on. It has a MAC Air Intake and has been well taken care of. Synthetics throughout and premium fuel.

Now that we are back home in flat Texas it is running fine, but this does tell me something is wrong and I need to address it before anymore highway trips.

Thanks in advance for any advice!

 

[dogfriend]

I would check the condition of the plug wires and check the resistance of the coil pack.