Symptoms
Thumping noise once a week it knocks about 4 times for a total of 2-3 seconds then stops not very loud and is coming from the passenger side. This has been going on for about a month . It is like a thumping noise and happens when I am doing about 20-35 mph.

THE ENGINE LIGHT CAME ON TODAY 1 MONTH LATER

I took it to Auto Zone today and hooked it up to the diagnostic machine and it came back a couple of things ..

I had the oil changed.

I did get gasoline today so I added fuel injector cleaner as well.

Any thoughts or suggestions... VB ROCKS !!

Thank you everyone
Vicki

 

What were the codes they gave u
as for a noise not much any one can help with that over the internet.

 

It says troubleshooting P3400.

I assume this is what the code is I am looking at a print out .

 

find out if U cant find it and the light is still on take it to a parts store and let them scan it for free and get the numbers.

 

Auto Zone scanned it for free the code is P3400

 

P3400-MDS RATIONALITY BANK 1

Possible Causes
INSUFFICIENT OIL PRESSURE ACTING ON THE LIFTER LOCKING PINS
OIL PASSAGES RESTRICTED
LIFTER
MDS SOLENOID


what engine size do u have ??

 

Trying to give back a bit....
I recalled this being discussed in another forum on the Hemi with MDS. I was able to find the link, which is here - has the troubleshooting steps. The MDS activation makes sense given the speed you were going. This article says you have to use 5w20 if you have MDS - also has info about a TSB and a "hard shift". I also recall there were reported issues when after market exhausts were installed on MDS systems.