First off this is my first post. This will be a series of firsts in this post. I'm a diesel guy. This is my first gas pickup. I recently bought a 97 dakota v8 mag 5.2L with 102k miles and needed some work. Among other things like ball joints and tie rod ends, I have changed the Trans filter and pan seal, oil filter and oil, changef plugs from Champion (436) RC12LC4 to NGK(4219) ZFR6F-11. I did use seafoam (dumb move on my part) prior to plug change in a full tank of fuel. So here's the issue. Prior to new plugs, I fueled up with new gas after running seafoam treated tank to empty, added a little cheveron injector cleaner to new gas after reading about seafoam cleaning so well it can plug up other stuff from the gunk breaking loose. speed was up to where it was prior to seafoam treatment. Changed plugs drove to work acted sluggish but not terrible. It's sat at work for 3 days while I worked out of town. Drove it home today and pedal mashed down 63mph max at 3000rpm if I recall. Did I loosen up to much gunk and plug stuff up? Did I mess up my cat or o2 sensors? Is there a Trans or axel sensor that could be coincidently bad? Carb/throttle body clogged up with stuff?? Fuel pump or filter messed up from the treatments? Please help me with my ignorant mistakes. Thank you for any help or Insight . Austin.

 

I haven't personally ever had issues with seafoam. Honestly you aren't going to have that much gunk in the fuel system. Unlike diesel injectors the holes are much larger and don't get plugged as easy. There aren't fuel filters on these. Just a pickup screen on the pump. Get a fuel pressure gauge and check for 50 PSI. Rev the engine while doing so. Also check the throttle cable for too much slack. Check the air filter/housing as well. Does it idle fine? No stalling?

 

Air filter is fine. Also new. Starts a tad rough but after 10 seconds or so it idles fine. 2 times with the seafoam treated gas it started up then bogged down then took off again which prompted me to change plugs after the next fuel up.

 

Check the fuel pressure. Sounds like a failed fuel pump to me. If you start it then let it smooth out and then try again does it start fine? The check valves on dodge pumps are almost always a failure point.

 

I will do that. Thank you.

 

Really one of the best spark plugs for those motors are the req. Champions. They are easy enough to change out as needed. As is a good quality dist. cap.
I would guess your O2/exhaust senors got a dose of whatever you are trying to burn through there.
Check for oil in the bottom of your intake ( flashlight straight down the open throttle body )
I guess that may throw a code/light ?

 

Today i tried to test the pump presure but theres a odd press on elbow where the port should be on the fuel rail. With out the proper equipment handy we tried a few other things, plugged in a code reader and got zero codes but the throttle position sensor is reading 13.4% at idle. Though this % is in the realm of normal, after reading up on the TPS the other symptoms are in line with a failing TPS and a idle air control valve could also be messed up. Will post a update tomorrow.

 

The TPS failing usually forces limp mode after a bit of driving with it. 5-6 miles or so. IAC usually just makes the vehicle not stay running after starting it so I doubt that is your issue.

 

What supadoom said. 13% is about right for closed throttle, around 88% for full throttle. if IAC was acting up, it wouldn't idle...has no affect on general throttle. And yes, the 97's don't have a fuel pressure test port. As the first year of OBD-2, alot of basic OBD2 diagnostic "tools" weren't developed or applied to the manufacturing line until the 1998 model year. Your issue sounds more like a MAP sensor issue, honestly. You might check for vacuum leaks (unlikely since it idles mostly fine) and check the 1/16" elbow that is under the MAP sensor. Those plugs might also be upsetting something in the spark process itself. I run the NGK BRK7E (#4644 I believe) plugs in mine.

 

Got the proper parts to build a test port hose adapter. Fuel pressure 10-11psi on turning ignition on. 22psi at idle. Lost 5 psi after shutting motor off after 20min. Ordered a pump assembly. Will see if that is my only issue. Thanks for the help