I got an engine noise going uphill which starts at 2800RPM. If I hold my foot in it for a few seconds the noise starts. Engine otherwise seems to run fine.

Here is what I have done in the past few days:

A) Changed my spark plugs, spark plug wires, cap & rotor. Marked improvement, but still have motor noise with a load on at 2800RPM. If I keep my foot in it, it hesitates, the check engine light comes on and the engine wants to die out. I let off just enough for it to start running normal again and everything is fine.

B) I changed out my Oxygen Sensor yesterday evening, but have not been able to fully test it on the highway due to the traffic. The truck does make the same noise to some extent, but the, "Check Engine Light" doesn't come on. I think it still will because I could not hold it due to traffic.

Notes:

- Oil is black. I change my oil at 3,000 miles. The last 3 times I used 1 Qt DuraLube to the 4 Qts 10W30 Castro High Mileage Brand. I still have a little more than 1000 miles to go before the next oil change. Seems kinda soon for the oil to be that black. Oil level is right up to the mark on the top side of the Safe Zone.

I am kinda concerned I may need a valve adjustment/job. I hope not. I just got an over the phone estimate for a valve job @ $830.00.... Don't need that kinda expense unless it is the problem. Hope not.

Could these be some of the avenues to approach? Which one/s should I do next?

- Motor Flush and change oil to 10W40, Brand Name Synthetic Oil.
- Clean and or replace fuel injectors. I assume this truck has it.
- Mass Air Flow Sensor replace. I assume this truck has it.
- Fuel injector treatment in the fuel tank.
- Possible change transmission fluid and modulator/transmission filter.

What should I do?? I am getting frustrated. Don't want to see the mechanic If I can help it.

 

check your plenum gasket, it'll rob power and mpg and cause your motor to run rough... do a search on it and there is a link to a tsb that tells you how to test it to see if it's leaking...

 

Yes definately, my plenum is bad, breather is pulling 15lbs of vacuum. rough idle, spark knock, and the plug on back of motor, pass. side stays covered in oil.

 

I am still troubleshooting my engine noise @ 2800RPM on my 1999 Dodge Ram, 5.9L Pickup Truck.

I understand that the plenum gasket is probably the problem. I haven't looked down the throttle-body yet for oil. That is my next step.

I did some further investigating. I went to the libarary and looked up in the Chilton's to get more detailed information.

You mentioned the plenum gasket was located on the intake manifold, which me made wonder how hard it was to get at and If I had the ability to replace it myself.

It looks like I could probably do the job but I was not satisfied with the lack of detail that Chilton's presented in their manual. Haynes Service Manuals are worse concerning lack of detail.

I could probably do the job with the Chilton's Manual but sure would appreciate a better detailed book.

I was hoping to get a book specific to the year, make & model of my truck which has specifications, torques & trouble shooting guides & special tools needed for the job included.

The first place I looked was Dodge. Couldn't get a manual where I looked. Guess they like to sell them but not assist the owner in how to fix them.

Do you know where I could go to get what I want/need.

 

heres a helpful link... plenum gasket repair

and the TSB on it as well... both have repair steps...

 

oh yeah, you needed a manual... here you go... download it from a link on this thread... service manual