64 replies to this topic

[Volvo5.0]

This is based on Lucky's SAS delete thread http://volvospeed.co..._1#entry1765975, so obviously he deserves credit. It's only been tested for a few days so I'm not ready to claim victory, but so far it looks good.

I'll preface this the way Lucky did....*THIS IS FOR TRACK CARS OR DEDICATED NON ROAD GOING VEHICLES, ANY TAMPERING WITH FACTORY EMISSIONS SYSTEMS IS A VIOLATION OF FEDERAL AND STATE LAWS*

There were mixed reviews on the "diode" fix, but I decided to try it anyway. I installed the 1N4003 diode between the A32 and B38 terminals and still got a CEL. I have a Volvo System Tester (VST) so I'm able to run a test of the SAS system any time using the VST....





Using a breakout box I was able to install the diode easily....




As the test was running I could see that the diode caused an immediate drop in voltage from the front O2 sensor when the air pump started. Still the SAS test failed and I got a CEL. I tested a different car with a good working air pump system and found that when the air pump turns on there is a delay before the voltage from the O2 sensor drops. I think with the diode setup, the voltage drop happens immediately, which the ecu interprets as a fault. I think the series of events in the test are... 1) air pump starts 2) solenoid valve opens 3) THEN the voltage drops from the front O2 sensor

The immediate voltage drop after the air pump starts indicates that the solenoid valve may be stuck open and sets a code for flow malfunction.

The answer would be to delay the voltage drop through the diode. According to Vadis the SAS test needs to run within 6 seconds. I'm sure Lucky could throw together a Time Delay Relay (TDR) easily, but I looked around and found this http://www.wolstente...edelayrelay.php

Hooked it up to the breakout box and set the delay to about 5 seconds....




Success!!! I ran the test with the VST and it passed. Nice thing about the breakout box is I could test it on different cars easily. Tested it on 6 different cars (turbo and non) and all were successful. The relay and diode have been installed on my S70 for 3 days. I've driven a couple of hundred miles and so far it's good. I know sometimes it takes awhile for the CEL for the air pump to resurface so right now I've got my fingers crossed.

Edited by Volvo5.0, 08 October 2010 - 03:02 AM.

[rj240]

Nice!

[RZT5]

looks like i might have to do this

[jdlc]

Thanks - I was about to reinstall my SAS system because of impending smog test on my JOYDT5M.

Now, hoping this is the SAS bomb, all I have to worry about is the cat before the test : )

[nocturnal7x]

Thanks - I was about to reinstall my SAS system because of impending smog test on my JOYDT5M.

Now, hoping this is the SAS bomb, all I have to worry about is the cat before the test : )

try to pass without a cat. I miss not having a stupid cat.

[flaco]

Can you try to run the diode alone, but instead of using the pump terminal B38 use the solenoid terminal A37?

This might still work without requiring the delay box...

[lookforjoe]

Nice Work!

I wish I had that breakout box, would make life much easier for testing all kinds of adaptations!!

[fischmama]

+1 !!!!!

[cheapwagon]

Would this be the same for 97's with SAS?

[Volvo5.0]

Would this be the same for 97's with SAS?

Motronic 4.4.....Yes

Can you try to run the diode alone, but instead of using the pump terminal B38 use the solenoid terminal A37?

This might still work without requiring the delay box...

I looked at the schematic and that actually may work! The air pump is not what needs to trigger the voltage drop from the O2 sensor. The solenoid valve when it opens would probably be the best trigger. I have a couple of cars here today that I could use as guinea pigs. I see if it works.

[cheapwagon]

Motronic 4.4.....Yes

Great I will give it a shot. Now if only I could do this with the damn EVAP P0455 code.

[Volvo5.0]

Great I will give it a shot. Now if only I could do this with the damn EVAP P0455 code.

Double check if you have 4.4... I know '97 was a transition year, some had 4.3 and some had 4.4

[cheapwagon]

Double check if you have 4.4... I know '97 was a transition year, some had 4.3 and some had 4.4

I don't think there is anyway to tell. I am just going what others have said and I swear I read that SAS is a part of 4.4 in V@dis somewhere.

[flaco]

I looked at the schematic and that actually may work! The air pump is not what needs to trigger the voltage drop from the O2 sensor. The solenoid valve when it opens would probably be the best trigger. I have a couple of cars here today that I could use as guinea pigs. I see if it works.

Any news on this?

[Volvo5.0]

Can you try to run the diode alone, but instead of using the pump terminal B38 use the solenoid terminal A37?

This might still work without requiring the delay box...

I tried running the diode alone (without the delay relay) between terminals A32 and A37. Oddly when I ran the SAS test with the VST it failed. Tried it on 2 different cars and failed on both. I really thought that might work.

Good news is my original setup, diode with delay relay, is still working fine (although its only been a week). I check it daily and have used the VST to run the SAS test several times. With addition of the relay I don't think it would be possible to do the work inside the ecu. It was easy enough to pull the ecu and remove the plastic computer housing and do the wiring in the harness directly below the ecu. Fingers still crossed

[flaco]

hmmm... I think the solenoid output may be PWM... which would defeat the solenoid-active to o2 drop connection...

GREAT info here!

[Volvo5.0]

I wanted to post a quick update. It's been 2 weeks and still no CEL or codes stored for the air pump system. I had a "scare" today when the CEL came on . When I got to work I checked codes and there was a code for a baro sensor. Totally unrelated to the SAS.

If I can make it to the weekend with no CEL then the turbo back exhaust gets installed with no provisions for the air pump

[jdlc]

I wanted to post a quick update. It's been 2 weeks and still no CEL or codes stored for the air pump system. I had a "scare" today when the CEL came on . When I got to work I checked codes and there was a code for a baro sensor. Totally unrelated to the SAS.

If I can make it to the weekend with no CEL then the turbo back exhaust gets installed with no provisions for the air pump

Done Hussein's and done Lucky's - now looking forward to this! As pointed out, inside ecu is not going to work for this mod.
Anybody got the info about what color the wires are for the affected pin#?

[Volvo5.0]

Anybody got the info about what color the wires are for the affected pin#?

A12 is blue/red
A32 is green/black
B38 is blue/pink

I did all the wiring under the ecu connectors A&B. The pin numbers are written on the connectors but are very small.

[brad1000]

Hi,
I'm new to the forum. I've read through the related threads and have a few questions

1. I'm unsure if I have the 4.3 system; how can I tell?

2. will the fix with the TDR & diode work on the 4.3?

3. if the relay and solenoid are still hooked up, is the use of the diode alone (without the TDR) a failed solution to the problem?

Thanks in advance.
-brad ('97 850 GLT, manufactured in 96)