jvanbrecht

Okay, so I have been trying to fix a CEL issue related to the secondary air injection

Typically it was P0810 and P0814 which are constant, and p0410, p0420 and p0745 show up periodically.

I have already replace the emissions hard line tubing which was cracking.

The pump works, and I know the air is making it into the engine as on cold start (or random test run of the Secondary Air Injection system), the engine idles at around 1k for 30 seconds before dropping back down to normal idle.

I did replace the check valve as well to be safe, although I suspect that was not it, but it was covered in crud and the intake filter was blocked.

I started with the cheapest parts and am working my way up, as the diverter valves are $250+ each.

That leaves the O2 sensors which are not exactly cheap either. At 96k they are probably due for replacement since Bosch recommends they be replaced at 100k miles.

But I want to make sure that I am reading the sensors right, the ones after the cats should be steady in voltage at idle once the engine is warmed up, the ones in front should constantly be changing between 0.1 and 0.9V correct?

I have a snapshot of mine over a few min period, the 2 prior to cats fluctuate with similar values, the ones after the cats, the left side is static (or mostly static) in voltage, the right one fluctuates wildly, similar to the precat ones.

I'm guessin the right post cat one is the one failing, and needs to be replaced in the interim to get rid of the problem..

Or could it be something else.

jvanbrecht

Bump..

Anyone...

shades

I'd say your on the right path...the rear o2 that is fluctuating is reading like the front, there's something going on there. usually when the rear acts like the front, means the the front o2 is done....im not sure why it's reading that way. as for the 410 and 420 codes...they are misfires on the cylinders. Could be coils or time for a tune up. Easiest way to check is to take a coil from, let's say 5th or 6th cylinder and swap them around. If that cylinder fires a code, you'll know it's the coil.

shaun.barnard

Sorry for waking the dead but did you find a solution to this, I got a cel today with P0410 Secondary air injection system, P0810 Clutch position control error and P0814 transmission range display circuit. After some research it looks like all these faults are related to the secondary air injection system. I had this issue before then deleted faults and cel went off till today again. The last time I spoke to the local shop the guy told me the secondary air pump is not really needed in our climate as it is always warm her in SA? And also apparently an expensive part so would not want to buy something not needed but that still leaves me with a lit up cel and also I'm the type that wants everything right as well so yeah...........Also read that it could be a faulty relay or damaged vacuum pipes but mine still look good "from above". So where do I start?

shaun.barnard

Fixed the problem. What a quickfix.

Jasonoff

You ask for help, end up not needing it, then don't even share the solution?

Nice one

shaun.barnard

The tease worked

Well it was a problem before that I had fixed but seemed the fix did not work long enough. It is a shaft that comes from a vacuum pump "thingy" to a ball that is connected to a valve inside the intake that has got something to do with vacuum and air. The ball connected to the valve on the front of the intake is worn and the shaft comes off. Last time i fixed it with cable ties and it was fine till now but it probably stopped working properly as the cable ties must've created more friction for the shaft to move less freely. So I loosened the vacuum thingy and squeezed the ball clip with pliers to make it smaller therefore to clip on tighter. Deleted the faulted codes and started her up and she's fine again. Don't think this is going to last long either but I will just look for the part number and order a new vacuum thingy with a shaft that clips on securely. If its the ball that is worn I am going to drill a hole through both and put a shaft through with circlips on either side. Not removing the whole intake just for that.



The ball with the ball clip shaft attached.



The vacuum thingy.

Tlnt60

There is another thread about this somewhere I read. I thought it had something to do with adjusting the runner length depending on load and RPM.

brettysetgo

Hey Shaun.barnard -
Did you get that part #? My C300 is throwing these same codes at me. Hopefully I can have a fix as easy as you said - I'd rather just replace the whole part if possible. I've been fighting this thing for years, bringing it to multiple shops who can't figure it out - if it's this simple, I'll be blown away!

shaun.barnard

Hi, I never replaced a part. I just removed the shaft and squeezed it slightly with pliers so that it has more clip if you will to stay on the ball. By removing that ball looks like you need to take the intake off to replace but it has held. If it did it again my next step would be just to wrap a layer or two of electrical insulation tape around the ball and spray it with and oil lubricant then clip the shaft back on so it can clip on tighter but still be able to move back and forth freely. Try it and let me know.

brettysetgo

Really appreciate the quick response! I'll tinker with it and get back with you.

Robert L

Hi there, I have code P0814 after I removed and repaired my intake manifold triangle lever. Put everything back together and this code has shown up? Do you think it's related to the tumble flap and swirl flap inside the manifold? I have ordered a brand new manifold as the long runners on bank 1 are still stuck closed and a new intake is only $200 now. This code was not there until I fixed this broken part so I am scratching my head now. The code was p2006 intake runner stuck closed which is still there even after I replaced the metal triangle. None of the vacuum lines or hoses have perished, everything holds vacuum.