Fara

Rusting through the battery compartment is not because of a lack of rust protection, but from 20+ years of battery acid getting on it.

mytrplseven

The battery compartment will rust out below the battery in most of these cars. The water leaks into the passenger foot well and gets into the ECU. pull the carpet back and look for water. Pull the battery and look for small (or large) holes in the battery box. I sanded mine to the metal, put two layers of glass on it (cover the threaded mounting stud with a paper straw) and then sprayed the whole thing with trunk liner spray. Now it looks and works great.

F18Rep

Yea, it does happen although I haven't seen it in my cars, I think the problem occurs because maybe the car gets parked on a hillside or leaves find there way in under the battery and block the drain. That makes for a puddle and nature wins that battle even against rust proofing. I do the engine bath thing pretty regular but don't own a pressure washer....Bruce

ZR8ED

I don't even use water to wash the outside of my car. I use Dry Wash N Guard. Been using it for more than 10 years now. When you own a 30+ year old Datsun, you learn that keeping the car dry will slow the rust down...early Datsuns didn't have rust protection...ughh.

Mr. 9Frank

Any other key points to look for while Im under the manifold? About to remove and inspect the idle control valve and check the speed/reference sensor. Also will check to harness to the MAF.
ECU area is completely dry BTW

szabon

my vote is you had a vacuum line that was old and dry, but not yet cracked. You then pressure washed the engine, hit the line, and viola! it is now cracked. A little water in the manifold will work itself out and not cause a continuous problem. It could be an electrical short, but I would go ahead and change out the vacuum lines anyway. You don't see fuel coming out of an old fuel line do you? (or smell fuel...)

Mr. 9Frank

No fuel smell or leaking.

Fortunately she has a good history and I have yet to find an over-aged hose or line. My marking of the wireset orientation was incorrect which was the reason for the start and die after re-installing the intake manifold.

So now she runs but still in limp mode. The throttle has absolutely no effect on the "limp mode" idle, which actually registers 0 vacuum on my gauge and 1 bar on the gauge in the cluster! TPS is plugged up. It idles this way until it finally dies after about 30 sec.

I have located one lonely vacuum line in the battery compartment. The line comes off a t-fitting from the brake booster vacuum hose. As of now its plugged. Does this vacuum line possibly run to the ECU and its simply come loose from a connector?

bw993

My guess is that your QUAD MAF is shorten due to water exposure. I had the same problem, since the QUAD MAF uses a local microprocessor that digitizes the data from the MAF sensors and the digital electronices are located right at the intake in the housing for the K&N filter. Not a great MAF design since the most sensitive electronics are located in a very exposed location.

I went through 2 QUAD MAF due to weather exposure.

Mr. 9Frank

Any methods of testing the Quad MAF, or visual inspection of a specific component of the MAF? Replacing it would require a re-program correct?

bw993

The QUAD MAF is programmed thru a micro-USB connecter on the housing. Try hooking your PC to the QUAD using the interface software to see if it will respond. If the QUAD is totally dead it will not respond to the software. If only the QUAD DAC drivers are damaged, the only way to test it is to bypass the MAF and hook up a AFM to see if your car starts and idles.

Mr. 9Frank

Ill download the software and see how it responds.

Any ideas on the vacuum line plumbed through the battery area?

Mr. 9Frank

The photo below is of a Saab automatic performance controller, part number 7517477. I believe it routs to the wastegate from two lines in front of the intake manifold. They have never been connected to anything and possibly used for a previous setup. It does have a hot electrical connection. Any deeper information on its purpose would be appreciated guys.

Mr. 9Frank

Ive determined the Saab APC was from a previous setup...

Now Ive broken the intake down, inspected to ICV and TPS which looked fine. The TPS is clicking in idle position. When I went to start the engine, it is still starting hard (which starter fluid does not affect) and idles very low at 0 vacuum. When the engine was idling, it would give off an indescribable hard poof/popping every few seconds (from the engine, not exhaust) or so and with each poof came a little white smoke from under the intake manifold. I believe the bad part has revealed itself but idk specifically were the smoke it coming from. Any further diagnostic tips would be great. Tomorrow ill attempt to see exactly were the smoke is originating and check the timing.

Mr. 9Frank

Still have yet to narrow things down much but at this point Im on the MAF subject. The engine now idles very low with 0 vacuum being produced but still idling until I switch the key off. The accell pedal also has NO effect on anything at all. Regardless of whether the MAF is connected or not, nothing changes about the limp idle, but it is getting powe for sure. Nor is it responding to the Abaco DBX software.

I know that when the unit was working properly for sure, having it unplugged would not allow for any accel through the throttle so the symptoms do relate but $400 for a new unit is not worth it, considering an OE AFM until I can upgrade.

I may be sending the unit to the manufacturer if their are no further methods of me testing it, but for the time being, any other suggestions will be appreciated.

bw993

If your DBX is not responding to the software it is dead and it is the source of your problem. Just hook up a AFM and your car should start.