Need Help!!! I've had a slight rough idle and what seems like a miss for awhile. The miss seems to be at around 50 MPH. The truck has power and runs o.k, but I only notice it when I'm out on the interstate giving it gas and when it hits 50 mph there is a miss and sluggish pull, but once I hit 60 it's gone and all is fine. It's a 2004 3.7 4x4. I've replaced the plugs, pcv valve, air filter, cleaned out throttle body and ran sea foam through it. Nothing has worked so far. Also there are no codes showing up. ANY HELP would be greatly appreciated. It has had all regular maint kept up, fluid changes and such.

 

Sound like a bad TPS. You can test the resistance with a volt meter:
-Remove the plug on the TPS
-Set the volt meter to 20k ohms
-Place one probe on the middle contact of the sensor
-Place the other probe on either of the two other contacts
- Open the throttle slowly and watch the meter. The numbers should gradually increase (or decrease depending on which contact you choose). If there is a bad section, the numbers on the meter will quickly fluctuate out of sequence.
If you need a visual, there are multiple vids on youtube.

 

that reall sounds like a blown plenium gasket. my truck is doin the same thing and its very commont on the 5.2 and 3.7 with the kegger intakes. if you go to the 2nd gen dodge ram site and look at the top were it says end all be all plenimum gasket it will tell you every thing you need to know hope this helps ya man

 

Thanks to both of you! I'll check out both and see what happens.

 

I've been told that you can pull the oil dipstick out while the truck is running and put your finger over the tube and if you feel vaccum it's for sure leaking. Is this a viable test as well as looking inside the throttle body. Also, if I need to change it how hard is it to change on the 3.7 and what all will I need? How long am I looking at to do the job? I've read posts on the 3.9 and bigger engines, but wasn't sure if they were all the same to change them out or if there were any tricks to doing it.

 

im not to sure about what kinda intake you have. is it the kegger? my 5.2 intake is leakin and i havent had time to fix it yet. i have worked on a lot of motors and im not to worried about the job.

 

I went ahead and changed the TPS sensor and it did not fix the problem. This is my first Dodge since I was a kid so I'm not sure if I have Kegger intakes. I tried to look down the throttle body for oil and it looks like there is some there. Will this Plenum gasket leak actually cause an engine to miss and run rough and cause fluctuations in the rpm's and stumbling / loss of power when driving? I've also read it could be two different problems, torque converter kicking in and out and a bad plug wire or something. I don't know except I want it fixed without spending an arm and a leg on it.

 

i know it will cause the missin and run rough. mine hasnt really lost power tho. but if you can see oil down the bottom of the intake that would be my guess. i changed my oil one time and used syn oil and it got really bad. the synthetic oil was to thin with that gasket the way it was. so i changed it and ran 10w40 castrol. with a half a bottle of lucas oil addative. the truck ran a lot better with the thicker oil and it isnt consumin it as much now. hope this helps