2ndof2

If replumbing the system like we saw at the beginning of this thread showed effectiveness in blowing air on the cats (that IS what this whole SAI issue is about no?) then I don't see how that can be a violation of anything. The computer will say things are aok. The little black box method does not remedy the air to cats issue so that would have to qualify as an "off-road" use in my book. With my car having been pre-owned, if ever questioned, I'd just blame everything on a previous owner so long as there isn't any sticker or something on any of the parts showing when the tubing or computer was manufactured!

vjd3

Laws will vary by state. In Massachusetts, "temporary" repairs which do not change the basic functioning of the system are okay. So, here, re-routing the air plumbing would be permissible.

Fooling the computer, however, would be a no-no. Seems like both systems are comparable in terms of cost; why not do the "right" thing that still allows the system to function as Porsche engineered it, i.e., getting fresh air into the exhaust to heat up the cats?

I had my guides done at 60k miles, and they needed it, they were pretty much shot. The car now has not used a drop of oil in 4500 miles, runs better and no longer throws codes. $3500 well spent, I think.

jimbo3

[QUOTE=jrb964;4458767]
We used 1/4" OD aluminum tubing. Fitting were fabricated to to the SAI valve and on the tubing in the injector ports. I'll get pictures of the valve this week.
QUOTE]

Are you able to get any pictures of the valve and fabricated fitting? How is the bypass working out since your last post?

Thanks for a great write-up. Might have to get John to put it in the DIY forum.

-Jim

Rick Lee

Subscribing.

BTW, I'm no lawyer, but I don't know how the EPA could come after the Turbowerx gizmo. It doesn't affect emissions, right? There are plenty of quick fixes to get an OBDII car to pass emissions, which are undetectable but make the computer tell the tester all is well. And there are plenty of chemicals available at any car parts store that are supposed to help you get through emissions. Seems to me emissions tests on OBDII cars, if mesasuring emissions is really the goal, are severley flawed. You can fail for a CEL that has nothing to do with emissions. And you can pass if your readiness codes are reset and stay that way for just a few minutes, though you could really have emissions issues. When I went through this a few weeks ago, my emissions test report had "N/A" stamped in all the boxes for PPM readings, but "PASSED" stamped in the boxes for this or that code being set to ready status. That's ridiculous. Typical gov't. bs. My car could be getting gallons per mile instead of miles per gallon, burning as dirty as a Trabant, but darn it, if those readiness codes are reset and I get to the station at the right time, I pass.

jimbo3

JRB- Any update on this? How many miles are on it and how is it working? Any problems? Is it working on other vehicles?

Thanks-

Jim

jrb964

Just an update on my SAI problem.

A number have asked for pictures of the top. Attached is a picture of the top side plumbing.

My CEL light came on after 2,000 miles. On review of the situation it was determined that it is the “fix” is still good (plenty of pressure). The problem, with 78K on the car, appears to be the O2 sensors. We did not replace the O2 sensors yet, reset the code and will wait until it happens again and then replace the O2 sensor on the right bank.

Will keep you posted.

Deadeye

Thanks for the photos! Looks like a fairly straightforward job, but I'm curious about the CEL that you got after 2000 miles. What was the code number that came up on the OBD2? Was it a SAI code or an O2 sensor?

Dennis
___________________
96 C2 cab

jrb964

Dennis, The code only showed one bank. My mechanic did not remember what the number was, but did feel it was a "weak" O2 sensor.

Deadeye

jrb, if it happens again get the code(s) from the tech and post if you can. Valuable contribution to the SAI saga. Your fix may be the most economical and permanent.

KMASS993

Hey Guys,

New to the board but interested in the external plumbing solution. Quick question, is there any way to just put in a small airpump with similar pressure, that would turn on when the regular pump turns on (and off), leaving the original system intact (hoses etc), and just connecting the the pump to two steel braided hoses that attach as shown in the first picture sent by JRB? I am more interested in a quick removable solution that can help kill the codes. I can live with the light on, but not the car in the driveway for continutious emissions failures!

Thanks and good luck to all with this awful problem!

Kevin M

Mike J

This would work but it would fail any visual inspection unless the pump can be hidden. Its not hard to tap off the output of the pump since its a rubber hose that connects the pump to the distribution housing/valve.

I was thinking of fabbing one up for fun but have not had the time.

Cheers,

Mike

KMASS993

So are you saying just to use the current pump set up? Tapping the output from the pump and rerouting it around with the tubing as I spoke about above? As JRB did but not worrying about the checkvalve (requires a lot of work). My only worries would be leaving the existing system open in someway. Thanks!

Kevin

jimbo3

If the existing system is already plugged up with gunk, it's doubtful that leaving it open at either end is going to adversely affect it. I would think that one could simply cap off the SAI check valve, then run a single tube from the pump to the rear of the engine and split it to go to each of the two exhaust pipes. Haven't looked, but there is probably a way to run the lines where it would be hidden from a visual inspection, or at least appear "stock".

I agree that modifying the check valve and running two tubes from it looks overly-complicated and may not be needed.

-Jim

KMASS993

I agree, I must say I am not too experienced in this department but facing a $500 bill for a check valve sucks, especially when I have a clutch replacement coming up in the spring might push me to get involved. I figure if I can get something going to keep over to then and get the sticker, I can replace the valve when they pull the engine for the clutch replacement (hence the temporary factor involved). I am going to try to attempt this on Sunday. How hard is it to access the air output on the pump? Thanks for the help.

Regards,

Garth S

There is merit to having a check valve downstream of the air pump.
A major component of exhaust gas is water (vapour), and exhaust will backflow into the supply lines once the air pump shuts down ..... which is >99% of running time.
The water drops out as condensate, for the now stagnant lines act as air cooled condensers ( get the irony ) - and potentially corrodes the crap out of the SAI pump. Those pumps are worth a few $$, and no great fun to get at.

This is a primary failure mechanism of the SAI system on the 1.8Turbo engines on Passats/Audi A4's - when the vacuum actuated 'Kombi' valve fails to adequately close the SAI air inlet to the back of the head .... another evil system