Hi,
I have a 2001 dodge ram conversion van with a 3.9l engine and a 3 speed trans. It has @70,000 miles on it and had always been good to me until recently. About 3 weeks ago it began to sputter and run rough upon heavier acceleration, this problem was only intermittent and didnt bother me much, but as time went by it slowly became more often and upon lighter acceleration. Now it is running rough as soon as you start it and doesnt come out of it and today the check engine light came on. It still runs and hasnt stalled on me yet and gets me to work but im thinking not for much longer. The timing of this could not be worse as i just relocated to a new area and have very little money until my new jobs paychecks start rolling in and I can start to catch up so I cant afford to try several things to get an answer and im really not in a position to pay dealer labor rates at this time. Any help would be appreciated.
Thank you

 

I guess that's a V6... I don't know, but I think all the V8s and V6's of that time period (97-03?) had a problem with the plenum gasket coming disconnected from the intake manifold causing vacuum leaks and high oil consumption. At least they gave instructions on the V6 replacement on the All Data website under the TSB. I have not re-subscribed yet, so I can't see it now.

But have you done the "easy" stuff first such as new rotor / cap and new plugs? Also at least be sure the plug wires are tght in there loom holders or even replace them, too.

Cheers,
Lee

PS: Other symptoms of plenum probs: Oil Consumption, High/Rough Idle, Inscessant Knocking (even with premiuim fuel).

 

milehigh7,

I got a 2000 3.9L V6 conversion with 3-speed.

Since the check-engine-light came on, you can do the on-off-on-off-on with the key without starting the van. Then look at the mile odemeter and read the codes that will flash in the display. Write these codes down and report them back here to us.

You can search for the codes on the internet via google or read them in the Haynes Auto Repair manual for Dodge Ram Vans 1971-2003, book number 30065 at your local autostore.

Other than the "tune-up" of cap/rotor/plugs/wires/coil, you could have clogged fuel injectors. That's the first thing that ran through my mind when you stated, "... it began to sputter and run rough upon heavier acceleration, this problem was only intermittent ..." You'll need to dump STP or Wal*Mart's TECH concentrated gas/injector cleaner into a 1/4 filled gas tank. These to brands do NOT have harmful alcohols in them. You may need to run mid-grade or super in the van for about two fill ups too. O-U-C-H since gas prices are up there, but it sure beats the cost of replacing the injectors!

Before you look at the BiG job of plenum problems, take a flashlight and look down the throttle-body (TB) while the butter-fly valves are opened. If you see oil in there, then that's the cue the plenum has gone bad. [:-]

Post your codes here too! There are some really good people here in the forums that can help when the codes are known. [&:]

 

Hi,
I want to thank you guys for the suggestions and I wanted to let you know that the day after my post my van began to run perfectly again. The problems just went away although the check engine light is still on so I fear the problems may come back but its been almost a week. I dont know, maybe it was the large amount of rain and humidity we had here for a while and the fault code can be cleared? or maybe the problem will come back but I wanted to report the fault code on here for anyone thats interested. The fault code is P 0304 and I am reading that to be a cylander #4 misfire. Do you think this problem can just go away? or is there anything I can do to insure it will not happen again? any suggestions would be appreciated. Thanks again for your concern!!

 

milehigh7,

If you just have a misfire, you may need to run a tank or two of fuel from another gas station.

Another inexpesive tip is to run a bottle or two of injector cleaner to a 1/2-tank of gas before replacing parts.

How's the cap-n-rotor, plugs, and coil?

Another item to look at is the "knock sensor". If you had the plugs changed and the new plugs went bad shortly down the road, then the knock-sensor usually has gone bad.

Have you had the IAC cleaned as well? Usually that's a typical item to clean after 60k of miles. Here's the basics to clean that ...

How to Clean the IAC Solenoid:
This is recommended at every Tune-Up to prevent excess carbon buildup on the IAC plunger. In some cases, you'll notice a slightly erratic idle quality. This is the first step in taking care of that problem. IAC = Intake Air Control (Solenoid).
• Remove the Air Hat from the Throttle Body
• Disconnect the sensor harness from the IAC Solenoid (Rear of Throttle Body)
• Remove the two Torx-25 Screws
• Remove the IAC Solenoid (Be careful not to lose the rubber O-Ring)
• Spray some Carb/TB Cleaner in the IAC port on the Throttle Body and let it sit
• Spray some Carb/TB Cleaner on the tip of the IAC Solenoid and wipe clean (Do NOT forcefully twist or push the plunger - You will damage the Solenoid. Wipe very gently. Do NOT let the pluger travel more than a 1/4" either. (That's what my Haynes Repair Manual states #30065))
• Spray a little bit more Carb/TB Cleaner in the IAC port on the Throttle Body and wipe clean with a thin/lint-free rag
• Reinstall the IAC Solenoid (Make sure you don't lose the rubber gasket on the solenoid)
• Reinstall the sensor connector and airhat
• Start the engine and let idle for about 1 minute.


Since the engine seems to be running fine again, the compression in #4 could be caused by other factors mention in this posting. If the problem didn't go away, a more detailed study of #4 would have been needed.

Hope this helps some!

 

Sorry to highjack this topic, but I was wondering, should the interior of the manifold be completely dry? I just took a look at mine with the TB off and noticed there was a thin layer of oil on the walls and pan, but not much. Should I look at replacing the plenum gasket?

 

Yep. It should be dry in the plenum.