Stemmer

Today my '99 RX suddenly began riding roughly and a flashing check engine came on. I checked it twice and it came up a single code: P0305. Unless I'm mistaken the problem is typically a failing ignition coil for spark plug #5, but could also be the plug itself - a failing plug seems unlikely as I have under 100k on the last set of plugs and since this code with the RX seems to largely be the ignition coil.

I'm not handy but would like to fix this cheaply. I have a grease monkey style indy mechanic who is not big on diagnostics but if you bring him the part and tell him the labor, he does it right and cheap.

1. Can I just buy the ignition coil or is there too much of a possibility of another cause?
2. Also, if I can just buy the part, can anyone help me with the correct part number for an Amazon purchase? It seems they are Denso parts but I'm getting many options when I enter "ignition coil" for a '99 RX on Amazon.

Thanks.

salimshah

#5 is closest to the driver, so not so easy to get to. I would make sure what is failing .. the plug or the coil. In either case dont buy OES and stick with OEM.

Salim

rosen71

1-3-5 is the sequence from left to right, standing in front of the car. It is easy to be changed. But first thing you should do is to change the coils of 3 and 5 and do a test again. If it is the coil, another error code will come up.

salimshah

hmmmm!
Salim

rosen71

Maybe I was wrong.
The 2-4-6 are in front.
But anyway, finding the problem is the same.


The coil on 5th is the hardest to reach and change.