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1996 Dodge Neon Backfiring and power loss* Solution Found!

Back in February I posted up the question below and got several responses. Unfortunately, the topic is now closed so I thought I would repost it after finding the solution.

I replaced the crank shaft position sensor and it fixed everything.

According to the Hanes Manual, the crank shaft position sensor is responsible for many things including timing etc. But one thing that caught my eye was that the car would run for a while, then stop completely and not run for a few hours or few days.

All seems good now.
Hope that helps anyone with similar problems below!

From the title post above, you can see that I have multiple issues with the car, or just maybe one causing all the symptoms.
First, I am an American living in Norway and getting anything done around here costs an arm, a leg, and an extra pinky so I am going at this the maker way and trouble shooting my problems with the car.
The initial problem is this.
When the car starts, it starts up fine and has normal power. After driving for a few minutes, the car starts exhibiting the following symptoms.

  1. If I step on the gas pedal hard and hold it, it sounds as if the car is drowning, the car loses power, then may back fire, then instantly, it regains power and accelerates. This is by keeping the pedal down.
  2. If I feather the pedal, it doesn’t lose power and accelerates decently but as soon as I begin to go up hill, it bogs down and does the drowning noise again.
  3. I created a video showing this issue for my friend Ken who typically helps with these things.
    Here is the link
    http://www.youtube.com/watch?v=Ba6B3ZdAt0w

In the video, the car is idling fine but when I throttle it, it begins to drown, then just picks up right away for no apparent reason.
4. Just two days ago, the car will not start after it’s been running for a while. If I let it sit, it starts up again.

Ideas of what it could be.

  1. Could my catalytic converter be bad and therefore it somehow creates back pressure after the car warms up?
  2. Would it be a fuel injection problem? I put fuel injection cleaner in the tank and it seemed to run a little better.

Any help is appreciated.
Thank you!
Miguel

Here’s the original post and responses!

Update!
Okay, so I finally got some parts from the US and so I wanted to share with you the results.
First of all, I had a suspicion it was the EGR valve based on the Car Talk discussion comments, the Haynes manual and my dad.
Can’t afford to buy a new EGR valve so I took the existing one out and cleaned it.
Talk about a bear of a task. Getting the EGR valve off requires removing four screws. Three of course were easy, the 4th one, under a small exhaust port, was difficult to reach due to my hands aren’t the size of my daughters and my extension was a bit too long and the battery holder was getting in the way.
So I removed it, cleaned it out with carburator cleaner. To clean it out I didn’t have one of those nifty suction guns but I did have a one way valve from an aquarium ($1.99) so I stuck that onto the hose and sucked on it (not inhaling) which then opened the valve and kept it open. I then sprayed carb fluid in that and cleaned it.
Result: Car didn’t hesitate or backfire when going uphill or with loads. Car still had low power though.
Next change: Spark Plugs. Simply replaced the sparkplugs which increased power.
Last change: Changed the fuel filter (thank God it was an external one). Based on my blow test, the old original fuel filter was rather clogged. New fuel filter rocked. Acceleration problem solved.
This is also a bear getting into the bolt that holds the thing.

Final results: Still slight hesitation so I need to probably replace the EGR valve with a new one but car now runs smoother.
More power probably due to new sparkplugs.
Better acceleration and no ‘drowning’ probably due to both EGR valve and new fuel filter.

So it was the EGR? I’m very surprised it didn’t throw a code. But congratulations on your clever solution. We always like to hear a happy conclusion.

I don’t have. code reader and the check enhine light turns on after the battery is dead but then goes away. I got a new problem but will repost on a different topic.