Damsel in distress, Please Help!! P2009, P0421

So I've had a few codes for a little while maybe 6 months and recently have been trying to fix it myself by reading this forum mainly. I've tried taking it to my mechanic but he doesn't understand what I'm talking about and jumps to replacing the pre-cat. If it comes down to it I'm fine replacing the cat if that is actually what needs to be done. I really Love my p5 so Please help if you can, I really don't know that much about cars but I am trying!

Also I'll mention that my car seems to be running fine. It idles fine, accelerates fine, no weird smells, my mpg seems fine.

This is what I've done so far.

When I first checked the CEL I got three codes, P2009, P0421, and P0660

I started with the P2009. I read that switching the VICS and VTCS plugs (White and Green) can sometimes get rid of the code telling you if the plugs are bad. I did that and also added some stuff to my gas tank that was supposed to help clean the 02 sensors and whatever else. I wish I could remember the name of it, I got it at autozone.

I disconnected the battery for a while and the CEL light went off. I then drove my car for about 5 minutes and the light came back on.

I got it checked again but this time only the P2009 was on.

I switched the wires back and disconnected the battery again. I drove a lot further this time, maybe 40 miles and the light came back on. This time it was only P0421. The P0660 has magically disappeared.

I tried some sea foam that I read about here, just a lot of smoke and when I drove afterwards my CEL was blinking until I disconnected the battery again. The code still came up after.

I have tried switching the two plugs one more time just for fun I guess with the same results. With the correct placement with the White plug on the right I get P0421. With them switched and the White on the left I get P2009.

My assumption is that one of the plugs, I don't know how to tell which one, needs to be replaced. If the P0421 goes away when switched the P2009 might be coming up because they are switched and one is bad. But what do I know...

Please help! I know there are a lot of threads on these topics, I've read pretty much all of them. I just need some new advice. Thanks!!

Blinking CEL means you have a misfire.

White plug electrodes are fine.

Whichever one is black is fouled and is the cylinder thats misfiring. Replace plugs and check again, if same issue replace coils.

How do you replace the plugs? Is it something I can do or should I take it to the mechanic?

Very easy, no need for a mechanic.

Do you have a spark plug socket and a ratcheting wrench? They usually come in socket sets.

You will also need a 10mm socket to remove 4 bolts that hold the coils down. Same socket as the one you us to remove battery terminals.



The red circles are the bolts you will need to remove.

The blue arrows point at the coils and boots that you need to pull out (Don't pull at the wire!!), if it is not coming out easy, twist it around at the boot as you pull. Do 1 at a time so you do not forget where each coil or wire goes.

Once you pull out the coil or wire, you need to stick a spark plug socket with an extension down and use your ratchet to turn counter clockwise until you can pull it out.

When you have it out, look at the tip of the plug electrode, what colour is it and how is the gap between the electrodes? Take a picture if you are unsure and post it here.

When putting the plug back in, tighten it by hand (extension), it should go in easy, if it doesn't pull it out and retry, otherwise you can get in trouble if you force it in there.

Let us know how it goes.

Your code reader gave a sort of "generic" code number for that 2009 code,... P2009 Intake Manifold Runner Ctrl Circ Low Bank1


Our car throws code P1569 for the same issue,.. P1569 Solenoid Valve Circuit Low Input,...
It sounds like you have a bad connection or broken wire on on of your connectors,... check this thread,..

http://www.mazdas247.com/forum/showthread.php?123839609-Could-use-some-help-with-check-engine-codes!

pcb said:

Your code reader gave a sort of "generic" code number for that 2009 code,... P2009 Intake Manifold Runner Ctrl Circ Low Bank1


Our car throws code P1569 for the same issue,.. P1569 Solenoid Valve Circuit Low Input,...
It sounds like you have a bad connection or broken wire on on of your connectors,... check this thread,..

http://www.mazdas247.com/forum/showthread.php?123839609-Could-use-some-help-with-check-engine-codes!

Click to expand...

These are the plugs that I switched. With the White on the right I get P0421 with the White on the left I get P2009. Not sure if I should replace one or both of these or if I should be looking elsewhere.

The_big_dill said:

Very easy, no need for a mechanic.

Do you have a spark plug socket and a ratcheting wrench? They usually come in socket sets.

You will also need a 10mm socket to remove 4 bolts that hold the coils down. Same socket as the one you us to remove battery terminals.

View attachment 207002

The red circles are the bolts you will need to remove.

The blue arrows point at the coils and boots that you need to pull out (Don't pull at the wire!!), if it is not coming out easy, twist it around at the boot as you pull. Do 1 at a time so you do not forget where each coil or wire goes.

Once you pull out the coil or wire, you need to stick a spark plug socket with an extension down and use your ratchet to turn counter clockwise until you can pull it out.

When you have it out, look at the tip of the plug electrode, what colour is it and how is the gap between the electrodes? Take a picture if you are unsure and post it here.

When putting the plug back in, tighten it by hand (extension), it should go in easy, if it doesn't pull it out and retry, otherwise you can get in trouble if you force it in there.

Let us know how it goes.

Click to expand...

Are you referring to the spark plugs? I was talking about the VICS and VTCS plugs. I think it was misfiring because I had just used the seafoam and it was still clearing from the system. I haven't had problems with my car misfiring before or since but if changing the spark plugs can help with the p0421 code I'll do it.

Here's a diagram of the solenoids,...



You had codes for both of the solenoids,... perhaps they both had poor connections that fixed themselves when you took them on and off.
Try the battery trick from the other thread to see if your solenoids are operating,...

Your P0421 code is probably correct,...

When certain codes are thrown, the ECU goes in to limp mode and floods the engine with extra gas. If you run your car like that for long periods, you could potentially fry your pre-cat.

You could do the non-fouler trick to clear that P0421 code ($10) or put in a new pre-cat.

You should leave your connectors properly connected and see if you get any solenoid codes again,... it take two drive cycles for those codes to throw and you may not have driven long enough for the ECU to register them yet,...

There's no big rush now cause your pre-cat is probably already dead.



PS,... 6 days is a long time for having a code (I can't imagine waiting 6 months,... code readers that broadcast to your phone are $10),.. a flashing CEL can wreck a pre-cat in less than 2 minutes,...

Br3sk1 said:

Are you referring to the spark plugs? I was talking about the VICS and VTCS plugs. I think it was misfiring because I had just used the seafoam and it was still clearing from the system. I haven't had problems with my car misfiring before or since but if changing the spark plugs can help with the p0421 code I'll do it.

Click to expand...

Yes I am, you mentioned your CEL was blinking, indicating a misfire.

Br3sk1 said:

These are the plugs that I switched. With the White on the right I get P0421 with the White on the left I get P2009. Not sure if I should replace one or both of these or if I should be looking elsewhere.

Click to expand...

After seeing how the white plug is connected to that sensor you should definitely replace it

That's my picture,... it's from a parts car I just bought. I think he deleted his VTCS and stuck on a breather to not throw any codes,...

How many miles are on the car?
I had a clogged pre-cat that I replaced around the 170,000+ mile mark.