DTC P0303

1997 DODGE RAM

138,000 MILES • V8 • 4WD • AUTOMATIC

IYAOYAS_AO

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i keep getting this code and it erases easy. this is what i have doe to the truck

i have changed the spark plugs, wires, distributor cap, distributor.

what i have seen, when i tow a trailer the light goes away, when i clean the fuel injection (stp) the goes away for about a day.

the engine does not shack or the act like it is missing a cylinder when on.

any ideals?

Jun 10, 2009 at 11:02 PM

KASEKENNY

CERTIFIED EXPERT
18,907 POSTS

More than likely you have a leaking injector. We can confirm this by checking the o2 sensor voltage and seeing if it is rich on that bank but based on what you are seeing I would go ahead and replace that injector.

Here are a couple guides that talk about this issue and give more detail on possible causes:

https://www.2carpros.com/articles/engine-misfires-or-runs-rough

https://www.2carpros.com/articles/how-to-test-a-fuel-injector

However, due to what you are seeing with the fuel cleaner and added load the misfire goes away, that is pointing directly to an injector issue.

Here is a guide that will help with replacing it:

https://www.2carpros.com/articles/how-to-replace-a-fuel-injector

Below is the process from the manual on how to replace the injectors. Please let us know if you have other questions. Thanks

Images (Click to enlarge)

Jul 14, 2021 at 6:30 PM