Just Do It Yourself

Okay, I'll admit it. I'm a do-it-yourselfer. I enjoy troubleshooting a problem, finding a solution and implementing a fix. I like the of fixing things, and I find joy in the outcome. In fact, it's kind of therapeutic for me to fix things when I'm stressed.

Over the last few weeks... maybe months... I've noticed that the engine in my truck has been surging. It started with just a little bit of fluctuation at idle. Over time, the fluctuation grew, and it started happening while driving down the road. It wasn't unsafe in and of itself, but after a while the truck started shifting into overdrive while highway driving on the smallest of inclines, and quite frankly, the ride became rough and annoying.

Today, I did a little bit of self-therapy and fixed the problem. It was a simple, inexpensive fix that just about anyone can do in their own garage. The rest of this post is going to be dedicated to helping other do-it-yourselfers. If you don't fit into this category, you may as well stop reading.

And of course, since we are a land full of lawsuit-happy attorneys and money-grubbers, I will throw in this disclaimer: What I'm doing here is simply telling you about my experience. If you ended up here because you were researching the problem I will discuss below, feel free to use my experience, but do so at your own risk. I'm not your mechanic, and I make no guarantees about your specific outcome if you try what I did.

Anyway, here's the scoop... I have a 2002 Dodge Dakota with a 4.7L V8. As I mentioned above, I've been having problems with engine surge. Research told me that there were a few things to try. And since they were all closely related, I took an and-all approach and did three different things at the same time.

1) I cleaned the Throttle Body
2)I replaced the Throttle Position Sensor (TPS)
3)I reset the Powertrain Control Module (PCM)

I'll give a brief overview of how this is done. Again, this is a guideline, not a step-by-step tutorial.

-In order to clean the throttle body, I needed to remove the black plastic shroud in front of the throttle body. This is VERY easy. There is a hose between the air cleaner shroud and the throttle body shroud. (These are my terms, not necessarily the manufacturer's.) At each end of the hose, there is a hose clamp. Loosen the hose clamps and remove the hose connecting the shrouds.

-Loosen the hose clamp on the back end of the throttle body shroud.

-Remove the two screws that hold the throttle body shroud to the intake, and gently remove the throttle body shroud.

-Inspect and clean the throttle body with throttle body cleaner. (For those of you familiar with carburetors, the throttle body looks like a giant one-barrel carb, and throttle body cleaner is similar to carb cleaner.) Caution: throttle body cleaner will damage plastic and paint. Follow their directions. (In my case the throttle body was surprisingly clean, but I cleaned it anyway.)

-Remove and replace the TPS. On the right side of the throttle body, there were two sensors. The TPS is the upper sensor. Pay attention to the reinstallation of the sensor. You need to line up the tines on the sensor with the mechanical end of the throttle body. (This sounds a bit convoluted now, but it will make sense when you do the replacement.)

-Reset the PCM. Unplug the negative battery terminal. Put your key into the ignition, and pretend like you're starting the truck for about 30 seconds. This will reset the PCM. This is necessary when you repair or replace electronic devices in the vehicle.

In my case, I am fairly certain that the TPS was the trick. But like I said, since I had the shroud off, I went ahead and cleaned the throttle body, and resetting the PCM was necessary following the replacement of the TPS.

After doing this work, I took the truck on a quick test drive - about 20 miles, both in-town and highway driving, and the problem appears to be 100% fixed.

I hope this helps someone else.