Ron

I've been told that GIAC will program the DME or whatever it's called so the check engine light will not illuminate for the SAI fault.

To have yours done you need to get your distributor to send it to GIAC with the stipulation that it is going in a car that will not be used on public roads, or something to that effect. In other words it's going in a track car.

Lorenfb

"I've been told that GIAC will program the DME or whatever it's called so the check engine light will not illuminate for the SAI fault." - Ron -

These guys make a lot of claims which FAIL to produce results.
Just "saw" a 959 chip that claims to result in USA compliance that had basically
NO change over stock.

"To have yours done you need to get your distributor to send it to GIAC" - Ron -

Distributor??

"From what do you base your opinion that it won't work?" - Mike J -

The OBDII Motronic must "see" less than a 50mv during the SAI test.

jstahmann

I tried to go the GIAC route and called them directly. Stone wall. I tried to tell them it would be a track only car and everything and they refused.

BTW, I built the circuit that has been posted here on rennlist and it works...

John

Lorenfb

"BTW, I built the circuit that has been posted here on rennlist and it works..." - John -

You had a CONTINUAL SAI fault which would not self-clear AND the ONLY mod
done was the use of the posted circuit, right? Furthermore, once the circuit was
removed, the SAI fault returned, right?

jstahmann

Exactly as you describe. I even produced a few and sold them, but after looking more deeply I realized I didn't want the Federal Govt knocking on my door and slapping me with a nice big fine...

Lorenfb

"In August the inspection/emissions test was required and the county gave us a 1 time exemption based on a sniff test of the emissions (which we passed with ease).

No check engine lights, I've attempted to follow every OBDII readiness code setting drive cycle that I can find anywhere, but no success." - jstahmann -

So, if the circuit worked, what's this all about?
The key is to get readiness completion & not JUST avoidance of a SAI CEL.
That's the reason, i.e. readiness completion, most/all late 993s fail the emissions tests.
If the circuit doesn't result in readniess completion, it has little/no utility.

jstahmann

The readiness completion failure is something else. I had my clutch replaced and since then the readiness won't set. Before having the clutch replaced the readiness codes set just fine with the circuit in place.

I've removed the circuit and the check engine light comes on signifying the SAI problem, but there are 4 or 5 readiness codes that won't set regardless of whether the circuit is attached or not.

Laura

jstahmann,
Have you looked into the readiness code problem further? Having a clutch replaced should have nothing to do with setting any readiness codes, what reason does your tech give for this issue?

jstahmann

He has no reason beyond theorizing that the ECU may have gone bad and is resetting itself on each shutdown/startup. I've asked the question here and I've heard that same answer or that the ECU is holding a power loss code that isn't allowing the readiness codes to set. I'm at a loss at this point.

I have figured out that the SAI issue and the readiness issues I'm experiencing are not related on this car. When the SAI bypass circuit is unplugged I get SAI related faults and the same codes fail to set.

I may just have to register the car in a county that doesn't require emissions inspections.

Lorenfb

"I have figured out that the SAI issue and the readiness issues I'm experiencing are not related on this car." - jstahmann -

But they are related. The SAI is one of the readiness states. Until the system
completes all the readiness states, the circuit's usefulness is questionable.
Furthermore, the 993 OBDII DME unit is very reliable and rarely if ever fails.

jstahmann

All I know is the following:

- CEL was on, SAI fault codes were causing it.
- Added SAI bypass Circuit, cleared faults. After driving, readiness codes all set no problem.
- Clutch replaced, still no CEL, no faults, readiness codes wouldn't set.
- Unplug SAI bypass circuit, CEL turned on, still readiness codes wouldn't set.
- Plugged SAI bypass circuit in, clear faults, no CEL, readiness codes won't set.

By the way, I give it about 2 months of driving between steps to make sure that all the cycles are being hit. I also go out and follow the driving cycle steps that have been posted here.

So, any ideas?

John