john.rogers

A diagnostic of my CEL indicates an OBD code of PO410. This is code for a "secondary air injection system malfunction". Anyone experience this code?

I was told the cause could be anything from a lose connections to a fuse, or more... (didn't sound that serious, however).

I was also told that the purpose of the secondary air injection system is for emission control on startup and that it runs only for a short while. The "malfunction" should not effect performance or damage the engine and is not related to carbon build-up.

Anyone experience this code? What was the fix? Cost, etc. etc.?

Advice.

Randy M '96 Silver 993

I too have the P0410 and I cleared it about 1300 miles ago. The previous one was 800 miles before that. I was told that this is the dreaded Carbon build up code, but who knows.

Check the archives for more (MUCH MORE) information.

ecobb993

Welcome to the club.

Jeremy Cottrell

Anybody had any success with this code lately

Joe L

Got this code recently. Promptly went out and performed an "Italian Tune-up" (drove for a while on the local highway system keeping the revs above 5k). Had to reset the CEL light manually, however the problem has not come back (knocking on wood furiously)...

Phil

p0410 = cyl 1-3 sec. air injection system blockage
p1441 = cyl 4-6 sec. air injection system blockage

I know a little about this today.

Randy M '96 Silver 993

6500 miles and counting since my last CEL. The port flush worked wonders!! Check the archives as this has been discussed recently.

hawk993

You might want to invest in a OBD II scanner for about $100 and you can reset the codes yourself. I got the CEL and those codes when I first picked up the car, reset codes, paid money for the reset, drove for a short while, got CEL again, AutoZone reset the codes after reading them for FREE, my Porsche shop's computer was on the road with their race cars, put my car in the shop once their computer was back, car sat there for a couple of days, cost me time from work to drop off and get the car, nothing done to the car other than diagnose everything again which was not cheap, I was told to drive it and bring it back when and if I get the codes again. I promptly went out and bought the OBD II scanner. I was also told by my Porsche shop that this is nothing to worry about, wont hurt the car... just my wallet from bringing the car back and forth and letting the shop reset the codes...

becker - 97'C4S

There has been a lot of talk regarding that ,(the dreaded P0410 code) if it's carbon build up there's not much u can do but open it up and clean it but the car runs fine. If u do a search you'll find that there was even a bypass
little DIY circuit posted.

It has to with the check up at warm up where the OBD2 does some checks and the carbon build up triggers it, those checks were not carried out in OBD1 systems so a pre-96 could have the same issue but the OBD just doesn't catch it. Try minor stuff some other users managed but if it's the Carbon thingie wait until you need some other intrusive work on the engine.

Cheers

Lorenfb

For more info on what really has occurred with the secondary air injection
system when it fills with carbon, check out this link:

www.systemsc.com/pictures.htm

You'll see how small the air passages are and the bends they make, resulting
in a very difficult cleaning effort without a partial engine disassembly and a
valve job to prevent reoccurrence of the problem.

john.rogers

As a follow-up to my original post on this topic ... over the winter I had the "dreaded carbon problem" fixed. About $5K. The carbon buildup looked like the pictures in the link in the last post.
I am sure you can "clean" the carbon out but it is a temporary solution at best. You have only moved the problem to the future or to the next owner. The fix is to replace the valve stem guides.
While the car is apart - the engine comes out for this fix - have the lightweight flywheel and clutch installed - about $1K to $2K. It is well worth it.
Just for info - my car is a 97 Cab with 50K miles on it.
Porsche quality?? Ya right!

993944S2

Is secondary air injection directly related to emissions? If yes, and the car will fail state inspection due to emissions problems, should not Porsche fix this under warrantee? Just a thought as come October 1st, a CEL will fail New York State Inspection...

Don

Dave Crellin

Sorry to hear about your CEL.

As suggested above by Randy, do a thorough search here - "SAI", "carbon-build up" etc. Learn as much as you can, and you'll see many comments and tips.

My personal view is that sooner or later you'll have to get it fixed. You can try the short-cut methods like MotorVac, and the "flush", but you may still be looking at a top end job down the line.

I had this, and bit the bullet to have the engine dropped and have new valves and guides. I still think Porsche should have paid given that the car was under emmissions warranty, but they won't.

Italian tuning, Chevron gas, and NO engine-lugging are the way to go to prevent it, once it's properly fixed.

finally, my view is that a problem here is that the ODBII systems required by law were beyond what the manufacturers could provide at the time. this was exaggerated with Porsche as they had to really push the envelope with the aircooled engine to meet emmissions levels, and then given the ODBII challenges..... This is one of the reasons why they switched to water-cooled.

The one real quality issue that i really think should have been changed is that the valve guides are made of a material that wears permaturely at the higher heats necessary for the emmissions levels. There is much about this issue in the archives.

slapshot

Hello John and others.

New member here. I'm in the early stages of getting my own 96-98 993 and have done a lot of background searching on the carbon problems and the CEL. From the gist of your post I take it your experience is that the full engine drop and valve redo is inevitable and that the flushes and other fixes are temporary at best. I have spoken with owners of MY 95's who are pleased as the ODB I does not cause the light, etc. However, from my study of this, it seems the 95s have similar SAI's that do in fact get the carbon build up too. Further, it is my understanding that on the 96-98s it is the CEL light being on (the computer read) that knocks one out of a "pass" for California emissions testing, not the actual emissions. Further the excess carbon does not measurably impact the car's health or performance. Thus the elaborate and DIY moneysaving resets, unplug battery, tape over CEL light, etc. tactics.

Is this a correct assessment of the situation for California standards? To get a nice car which checks out via a good PPI only to have the light temporarily fixed (DIY) by the PO (or just timing as cars I am looking for are in the 30-45k mileage range)and then have to dump 5k into a relatively perfect car for this basic sensor design screw up at some point shortly after purchase is very disconcerting. A real "bummer" to use a So. Cal. colloquialism. Any thoughts would be most appreciated. John? Phil?

hawk993

get the OBD II scanner and reset the code, it resets the CEL too(turns it off)...it will not hurt your car according to Master Porsche Mechanics that work on 993s all day long for a living.