[Bahnburner]

Hey all. My 2002 3.8 (111k mi) was idling rough, so I searched and looked for the usual suspects: plug wires (ok), plugs (replaced with 4-electrode plats), removed and totally cleaned throttle body, checked for vacuum leaks (ok), pcv valve (good). Same idle. Yaaarrrrggg!!!! Any other idears?

 

[shipo]

Hey all. My 2002 3.8 (111k mi) was idling rough, so I searched and looked for the usual suspects: plug wires (ok), plugs (replaced with 4-electrode plats), removed and totally cleaned throttle body, checked for vacuum leaks (ok), pcv valve (good). Same idle. Yaaarrrrggg!!!! Any other idears?

I'd start by losing the four electrode platinum plugs, most folks here (if not all) that have switched to them have switched back to the OEM/Champion single electrode/dual-platinum plugs.

Question, how do you know that your plug wires are good?

 

[underthehood]

He put his tongue on them and had someone crank the engine. Why? How do you do it? :blink:

 

[2002CaravanSE]

I used the Bosch +4 once in another car,they ran worse than the stock non platinum plugs.Lots of stuttering and uneven idle.Tried Bosch in an old Beetle,they didnt work there either.No more Bosch for me.

 

[shipo]

He put his tongue on them and had someone crank the engine. Why? How do you do it? :blink:

Just like that.

 

[V8Pacer]

Not engines can handle Plat. plugs. Switch back to OEM parts if possible.You maybe doing more damage than good. Check your wires, I have one once were the wire looked good and clean on both ends but the connection just inside the boot broke.

 

[Hokiefyd]

The stock plugs in these engines are Champion dual platinum plugs. Platinum works fine...as long as you stick with the stock spec.

But your point is good that all engines don't seem to fancy them. The engines in Dakotas, for example, just don't do well with platinum plugs. Even the platinum versions of the factory plugs. The Autolite 5224 works just fine in those engines. The AP5224 and APP5224 (single and dual platinum, respectively) just don't run well, even though it's otherwise the same plug with the same part number.

 

[2002CaravanSE]

In theory the fine wire of the platinum center electrode should take less voltage to light off.I guess just in theory...

 

[Jeepman]

Hey all. My 2002 3.8 (111k mi) was idling rough, so I searched and looked for the usual suspects: plug wires (ok), plugs (replaced with 4-electrode plats), removed and totally cleaned throttle body, checked for vacuum leaks (ok), pcv valve (good). Same idle. Yaaarrrrggg!!!! Any other idears?

Switching back to the OEM plugs might make a difference or atleast remove a variable. You didn't mention EGR valve. Do you have one?

 

[n8ech]

BB:

After 100k+ and 7 years, your OEM wires (if they are) are due for a replacement.

Does it only run rough at idle, or does it miss under load as well? Are you getting a CE light??

If the miss or roughness is present at all times, could be a failing coil pack.

Don

 

[Jeepman]

BB:

After 100k+ and 7 years, your OEM wires (if they are) are due for a replacement.

Does it only run rough at idle, or does it miss under load as well? Are you getting a CE light??

If the miss or roughness is present at all times, could be a failing coil pack.

Don

Good points n8ech.
Missing under load would also be an indicator of poor wires. I have experienced that with a 1995 Caravan 3.3L in the past. Replaced the wires and all was well again on the highway.