Hi guys,
I've spent the last few days looking for answers for my problems on my 2000 1500 van with a 3.9L and 3-speed auto. with 230 000 km on the clock (sorry for the long post)

First, I bought the van back in April with the check engine light already on. It ran good except for a slight whistling from the intake (can't tell exactly where it comes from), so I left it as is and focused on the front end that needed some serious work. I use it to take me and my girlfriend's dirt bikes to the track, once or twice a week. Well, last week end, the engine got louder. I had to go up and down a few big hills, and I noticed that it was clicking and knocking quite a lot when I put a load on the engine. It also lost quite a bit of power and sputters when I have to go up a hill from a dead start.

This week I found an exhaust leak (a broken flange plate) and fixed it, changed the plugs to NGKs (the old ones looked good) and checked the connections at both ends of the plug wires. I wanted to check the cap and rotor, but one of the torx bolts was seized so I left it alone. I also cleaned the IAC as instructed in one of the posts here. I unplugged the battery for about an hour and cleaned the terminals and all the grounds I could find. I then checked the code on the odometer after letting the engine run and it read P0505 (IAC). This afternoon during a test drive with the dog house off I noticed that the engine smells like burnt oil once it's warm.

I can go through a dirt bike engine easily, 2stroke or 4, but this is my first attempt at diagnosing a car engine and I'm kind of overwhelmed with all the sensors, multiple cylinders, electricals, limited space, etc.

The knocking and power loss are bugging me and I'd like to find the source of the problem before it leads to something worse. The engine starts easy, it runs perfect at idle, hot or cold (except a little clicking noise when warm). The noise seems worse when the engine is warm. It burns a little bit of oil, but not much. Fuel consumption was good before this problem arose, I got 16.5 MPG on my last trip with the cargo area fully loaded with riding and camping equipement.

If anyone could help me diagnose the problem it would be very appreciated. Also, would it be safe to keep using it and live with the problem until it is solved?

Thanks!

 

Kind of sounds like the infamous intake manifold plenum gasket, but I'm not familiar with magnum engines.

 

Here is the TSB for the plenum gasket leak.
http://dodgeram.info/tsb/2000/09-05-00.htm

 

Thanks guys, this is what I was fearing. Is there a way of checking that this is the problem without taking it off? Also, could it be the source of my air leak?

 

The diagnostic procedure is in the TSB article.

 

Oops, I missed that part. Sorry!

 

Alright guys, here's a little report on how things are going.

I did the testing procedure for the plenum gasket leak. The crankcase is building pressure so I guess the gasket is fine. Still I found a light film of oily soot in the manifold when I looked inside with the throttle body off. Maybe it's been changed but they didn't bother cleaning inside? if not, where could the oil be coming from?

There's one thing I noticed that I'd like some feedback on: when the engine is warm, the idle is kind of erratic, rather high and inconsistent. When I remove the PCV valve from its hose, the idle goes up (seems logical to me), and if I plug the end of the hose, the idle goes down to a low, consistent idle. Does it say something about the PCV valve, or anything else?

I'm still confused about the loud clacking sounds I'm hearing, and the whistling during acceleration is getting louder, so I'm guessing it could be caused by an intake leak. I suppose it could be caused by a leaky intake gasket?

I took my $5 spy cam and tried to record the engine at idle and at speed (about 45mph). Picture quality isn't good but it's the sound that matters.

http://www.youtube.com/watch?v=bXeddAeEetg
http://www.youtube.com/watch?v=xBH0vnROpiQ (5 seconds into the video)

Anyone has a suggestion to make as to what could be the problem?

Thanks again for the help!

 

Have you seen if the crankcase breather valve is clogged?


It is commonly overlooked and can cause sludge build up if clogged.

Have you checked for stored computer codes?

I cannot tell much of anything from your videos, and I even put on my headphones.

 

You also might want to change that PCV valve because it could be the source of the oil getting into the intake.

Have you done the IAC valve cleaning procedure yet?

 

Yes, that's the first thing I did.

I will take a look at it.

I only checked with the key dance and P0505 came out, nothing else. I have an OBDII cable on order from China, should get it next week.

I have to admit that it doesn't come out very good in the videos. It's kind of a tapping sound, which can be heard best from 4-7 seconds in the second video. Happens mostly when the engine is warm and under load. Completely unnoticable when it is cold.