Water in kick panel area! MAL 51! Stalling in traffic! Seems related somehow?

m3x1c0

Bad luck Buick
Joined
Jun 16, 2014
Time to let Bob off the hook on this one! For a while I suspected something wrong with my powerlogger that was causing me major headaches. I kept running into an issue where the car would stall for seemingly no reason. While sitting in traffic it would just shut off and eventually I'd get the cel flashing and code 51. I found that if I wiggled the the Powerlogger and put it back in things would seem to be fine for a few weeks. So you may understand I was giving the Powerlogger the sideeye and messaging Bob like crazy to try and figure it out. God bless you Bob for trying everything to help me but now I see that the Powerlogger likely has nothing to do with this issue! You are a champ for putting up with my BS my friend!

Moving on, about a month ago I pulled the ECM and found nothing obviously wrong except for some minor corrosion on the terminal leads where the ECM plugs into the main harness. This should have been my first clue that the issue was much deeper than the Powerlogger could cause. However, I cleaned up the ECM pins and used some of that dielectric grease on the contacts and the car did great for a month. Now I start to feel confident enough to do WOT pulls and do some tuning and just as I get ready to get some logs going Virginia decides to rain and rain and rain for almost 3 weeks straight now.

After all this heavy rainfall I noticed the car was being bitchy again. Shutting off in traffic dying at stop lights etc. and I am about ready to pull my hair out. After I calmed down and took the car back home I pulled the Ecm and as I pull it out of the kick panel I noticed a teeeny tiny water droplet on top of it. Then I looked and lo and behold the wires from the harness had some water on them. In this pic you'll see they are just barely damp (the black wires) after almost 2 weeks of continuous rainfall.
Photo May 13, 9 08 40 AM.jpg

I dug around and couldnt find any other evidence of water ingress on other wires but found that the carpet was a little wet and the little foam behind the kick panel was pretty wet as well. I then went about pouring 4-5 cups of water all around the area where the A pillar meets the cowl area but did not see any obvious leakage. I'm guessing this either a very slow leak or is behind the kick panel area and I will need to take all that plastic out to see it. The only other area with water on it was on top of this white door behind the black thing with the orange wire on it. It had a decent amount of water on top of it.
Photo May 13, 9 16 08 AM.jpg

Here is the area around the A pillar. The picture makes it seem rusty but I assure you there is none. But it appears whatever sealer was applied there is a little cracked?
Photo May 13, 9 21 33 AM.jpg Photo May 13, 9 21 50 AM.jpg Photo May 13, 9 22 00 AM.jpg
I feel like I am finally on my way to solving some of the strange gremlins I've had with this car since I've owned it. Does anyone have any ideas exactly what I can do to stop water from coming in? I've been told to check the AC drain but I need to make a trip to Michigan before I tear the interior apart. For now I will be putting the ECM in a plastic bag after cleaning it again but I don't want this leak to get worse or cause rust issues. Once again my apologies to Bob Bailey for the pestering as it seems this may have been the issue from the start! Cheers party people!
 
I have found that the ac box can get hair line cracks. Look closely and seal them if you find any. Good luck.
 
You can lay in the car while a helper hoses the car down. May help find the leak. Sometimes it's the windshield seal.
 
I have found that the ac box can get hair line cracks. Look closely and seal them if you find any. Good luck.
That's where I found my problem.Scrape the old crap off and make sure surface is clean.RTV a nice bead.Worked for me.Just my 2 cents.
 
Not sure if you need a water proof case but having it rotated so water can't collect in the plug.
 
If you could orient so putting the connector on the bottom and find slack for a drip loop on the cable you would be a long way to solving the problem
 
Like we talked about earlier, I suspect the AC drain. That door is recirc door that opens on max. The box probably isn't draining fast enough or at all and it fill up and leaks out there. Since you car is a hard top only so many areas to leak.

You can pull the top of the ac case off and clean it out in an hour or 2. Go through my facebook page I just did this to my moonroof car in the fall. Lots of pics. It was leaking for years and floor pans had serious surface rust on them. I fix the drain slapped in a new heater core and no more leaks. Also did the floor pans with por15, car will outlast any of us.
 
Ac box to firewall seam sealer is likely harder than Superman's head, and is cracked...
 
You will be addressing both if you take of the top off hvac case. Use 3m butal tape or any silicone to reseal the box.
 
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