Everyone,
I have a 2008 Scion xD manual trans with 150000 miles. I keep pulling code P03052 cylinder 2 misfire. I was replacing the coil pack every 6 months roughly.
In the last 2 days I have replaced 2 coil packs and a spark plug and I still keep getting the rough engine and the P0302 code. Any help here on what to look at next.

Thanks.

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Have you done a compression check?

 

Hey sorry for the late response I did a compression check and I am getting 65 psi across the board. Which seems really low to me there is 151000 miles on the car.

 

OK, if you trust your compression tester, the only other thing that I can think of that will drop your compression more than 50% across all cylinders is valve timing. Is there any sort of rattle on the end where the timing chain is? I'm betting the chain has jumped, or possibly one of the VVTI adjusters on a camshaft has stuck or failed.

 

thanks there is a slight rattle when i start but it goes away. I am still actively driving the car to and from work everyday and it tops out at 60 mph no matter what . and it will shutter and act like it does not want to go even when the gas pedal is all the way to the floor. usually when I am into 5th gear it drives find just can pass 60 mph however when i start from a complete stop it is hell for a few minutes.

 

OK, you are working on less than 1/2 compression on all 4 cylinders, so you need to figure out why. If the rings are extremely worn, you would be blowing clouds of blue oil smoke out your tailpipe. If, OTOH, your valve timing is terribly off, it would be either:

a) The timing chain has jumped timing, from either a broken chain guide, or a bad tensioner, or

b) The VVTI valve timing unit on one or both camshafts is malfunctioning. This may be because it's 'gunked op', broken, or maybe just a wire or plug is not connected.

From what you've told me, it sounds like you are just on the verge of bending valves from piston interference. I would assume that a malfunctioning VVTI unit wouldn't allow your pistons to hit your valves, so if that's it, I'd think you are safe for now. If, OTOH, your timing chain has jumped, your engine is a time-bomb.

Either way, I would think that your fuel economy is crap, either that or the engine is running so lean that you are in danger of burning a piston. This engine needs attention immediately.

 

Thanks for the info I dont know to much about cars so your help is much appreciated. I got another compression test set and i am gonna try that out and see what happens.

 

Well, if you "don't know much about cars", then the time to take it to a mechanic was probably several months ago!

 

I am mechanically inclined however having a mechanic do the same troubleshooting for a bunch of money is just not a an option right now.

So anyways, I have pop 4 new codes I redid the compression test and have gotten the same results.

The codes are as follows PO353, P0352, P0354, P0351 which are all ignition coil primary /secondary circuit, and I have also a number 2 misfire.

I have been led to believe that this may be an electrical ground issue.

Any Thoughts?

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If it's a "ground issue", the ONLY possible thing that it could be from is a malfunctioning VVTI unit. Ignition issues don't reduce your compression by more than 50% EVER. I assume you have checked EVERY engine fuse?

Face it, you are over your head, and you are causing damage to your engine every time you drive it like this.

 

so whats the result what happened?