Running rough after tuneup
 

I have a 2000 Ram 1500 conversion van with 5.2L engine. It currently has 61K miles and ran OK, but I decided to do a full and complete tune up since I am planning on doing a few trips with my family before year end. Also, the van has a new ECM as of 3 weeks ago.

Today, I replace the:
plugs
wires
distributor cap
rotor
air filter
PCV valve
breather cleaner
TPS
MAP sensor
IAC motor
removed and cleaned the throttle body

Tomorrow, I will replace both O2 sensors and change the oil and oil filter.

After replacing all the parts, I took it for a test drive and it had a slightly rough idle. When I get to 20-30 MPH, it starts to run a little rough and begins to shutter. Also, the exhaust fumes smell like it is now running rich (strong gas smell). Am I missing a step in the tune up process?

Check you wire routing from cap to plugs. There is a TSB for that. Search this forum and you should find it - I don't recall where it is right now. Also, make sure all your wires are pushed down all the way to the bottom of the sockets.

I'd bet 2 of your spark plug wires are swapped.

Thanks. I'll double check the wire routing and make sure I pushed them down tight. Also make sure all vacuum lines are good. If it's still running rough, I'll swap out the new TPS, MAP & IAC and reinstall the old ones to see if the new ones were faulty.

I'll keep you guys updated.

This was my first thought as well.

Also perhaps one wire is not properly seated on the spark plug as it is not always easy to get them fully on the plug and sometimes they pull back out of the distributor cap.

But do make sure they are not touching each other and are not going to touch any grounded metal with the doghouse re installed

Well you guys were right...I accidentally swapped the #6 & #8 plug wires. Ugh...so stupid! I also did the TSB on the wire routing. The van runs so smooth now!

Also did both the upstream and downstream O2 sensors today and tomorrow will be new Monroe Gas Magnums all the way around.

Thanks again. This site is great!!

Glad we could help you, and thanks for the update.