Ok here’s the situation and I’ll try to keep it short. I have a 1997 Dakota that up until a few days ago has run fine. Suddenly the other day the check engine light came on and the truck started running rough. Right after that I notice that my gas mileage is worst then ever (I get less then 10 miles per gallon compared to about 15 before). Any ideas on what the problem might will be appreciated.

 

I would check your codes, and it might be your O2 sensors

 

when did Dodge go to OBD II?

it is possible a plug or plug wire is bad?
If it is OBD II, it would pick it up and set the code for that sensor.....

However, checking codes is something you should do first...unless you know the trick how to short out cylinders which could save you a trip to get a scanner

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...Try the key on key off cycle to bring up the codes... For more info on this, use the search function. Once you get a code you'll have somethin to go from.

 

how long since a fulltune up?

 

I am going pull the codes today. As far as a tune up I bought the truck with 57,000 miles and put on another 10,000 and haven't gave her a tune up yet.

 

OK Even though I have a 1997 and the thread states for 1999 and above I pulled the code and the number 12 was all it read. I can't find anything more on that. Does 12 mean anything?