Hello,
I've asked a question on multiple forums a few times, so let me make this the best post out of all of them...
Recently, I bought a 1994 Dodge Dakota 3.9l v6 with 78,000 miles on it. About every ~60 miles, it seems to lose power while I'm driving. I'm not exactly sure what the correct term is here, but I'll give a better explanation:

• This happens when the truck is either cold or warm.
• Could happen 3 miles after the last time it happened... or 150 miles after.
• It idles fine while this is happening.
• When I try to put more power into the throttle, the less power I have.
• When trying to put more power into the throttle, I can hear a popping sound every few seconds, which is presumably a backfire.
• If I put the truck in neutral while driving (if this happens on a highway or something), and turn it off and restart it, it's fine for another 60 miles.

Now, I'll tell you what I've replaced:

• Throttle Position Sensor
• Crankshaft Position Sensor
• Camshaft Position Sensor (Pickup Coil)
• Ignition Coil
• Spark Plugs
• Catalytic Converter
• Distributor Rotor/Cap
• Idle Air Control Valve
• I'm probably forgetting something, but I think that I covered most of what I've done.

- I have an ECU on order to see if that'll help any of my issues, but that comes in a day or two.

If it's worth mentioning, the truck idles a little rough and I can feel a slight bounce when at a stoplight or similar. The tachometer shows only 400 when idling, but when I plugged in my scan tool, it is idling at 670-700, but jumping around. Also, the stock radio sometimes has an issue where it won't work for the first two clicks of the volume, but will then get super loud on the third click, and it will be super staticky.

Thanks for your time!
Parker

 

Have you tried monitoring fuel pressure when it acts up?

 

Stop throwing parts at it OK the sensors are old so you can justify that on age alone.
Other ideas to check, not throw parts at until you know, intake manifold gasket leak, CAT plugged, intermittent transmission problem. exhaust manifold leak.
Intake- look down the throttle body for wet oil
CAT- there is a temperature test. I forget if the front or back should be hotter at full temp.You need a laser temp gauge
Trans- ?? Find a trustworthy shop?
Exhaust- Mine made ticking sounds I thought were the tappets when I went uphill and was the most gutless then.The studs had broken.

 

Hi, I have a 93 that was giving me the same issues. I cleaned my fuel injectors and it solved my problem maybe it will do the same for you. Add some Lucas fuel injector cleaner every other time you fill up

 

Did you find a solution to this problem?

 

Wouldn't a manifold gasket leak throw a code for the IAT?

 

No. And they built them w/o exhaust manifold gaskets! I did put one in when I fixed the broken studs.
intake manifold plenum gasket leak is internal to the motor and allows oil to seep into the intake.
The sticky FAQ page explains the symptoms.