Everytime I change the oil on my car, it throws a code 34. I have to reset the ECM, and it will 100% go away until I do another oil change. Basic oil change, I don't do anything wierd.

The only difference between a start after an oil change, and a normal start, is that it takes a few seconds to build oil pressure after an oil change. But that shouldn't effect it.

Its not a big deal, like I said, unplug the battery for 20 minutes, and i'll never see another code 34 until next years oil change. But somethings not right about that...

Any suggestions would be greatly appreciated.

 

Try filling the oil filter while changing it. Just a thought.

 

You get a lot of these weird electrical problems. Change the oil and get a code for the MAF sensor That's so wierd. Are all your electrical connections good, because a lot of the problems you have always come down to defective parts, poor electrical connections or the ECM.

 

Stop changing the oil.

Your "problem" will eventually go away.

 

 

LOL, good one.........

 

So, just exactly what are you doing when changing the oil, besides the typical "drain the pan, remove the filter, install a new filter, fill with oil" routine?

 

This is exactly what I did. Jack up the car, remove drain plug, lower car, let it all drain out. Jack the car back up, put drain plug back in, remove oil filter. Fill the new filter with oil, screw it back on. Lower the car, pop the hood, poored the oil in, put the oil cap back on, and fired her up. I am 100% sure I didn't touch/mess with anything wierd. It is driving me NUTZ. Maybe you're right, I'm just going to put in Mobil 1 15,000 miles. And i'll change my oil every 7 years.

iroczracer07, the largest problem I ever had with my car was leaking injectors. The only code my car threw the 5 years of owning it was 34, after every oil change. I did find the source of a couple problems (stripped neg cable bolt) that kept coming loose. Anyone know how to remove the negative cable bolt that screws in the battery?

The only ecm problems I ever had was it dieing everytime I tried to datalog, which Craig Moates and I fixed by him sending me a new datalog cable.

 

I'd say something is shifting with the jacking up of the car. For the Neg. batt. cable, just replace the whole cable and have done. That way you can also clean the connections well while replacing it.

Try reproducing the problem without changing the oil by just jacking it up a couple times before stratup. :shrug:

 

Yea, this is one hell of a problem to chase. I've took it to the race track, whipped around autocross a bit, and it was fine. So it's not like something is really loose or shifting easily.

 

Off topic, but even synthetic should be changed every 6 months...not yearly. Its not just miles but time as well that deteriorates oil. Anyway, back on topic, after trying the jack deal, maybe try disconnecting the coil wire and build pressure first. Then plug it back in and fire it up and see if the code still pops. Maybe something in the ECM is off and is throwing a code when it sees low oil pressure. I don't know, sounds like a gremlin to me...try moth *****...

 

Thats what I was thinking. Besides this, my car is 100% fine and drives perfect. Electrically too.


Edit:

I never reset the ECM this time, just went out and started it now, fired right up no codes. Got a new Neg terminal too! :