99 2.5L Tip running on 5 cyl

[Adrian Thompson]

Quick history. I've had the car 12 years, put 50K miles on it. Had the trans rebuilt, security module replaced, etc. over the years. It's been running perfectly with nothing but gas, oil, tires and pads for the last few years.

So after being fine for ages, I had some stalling and non restarting when hot. New CPS and MAF element, and everything was perfect. After this work, I cleared all codes so I'd know if anything happened. Then I left the car parked outside, just once, and it rained. Now it's only running on 5 cylinders, and I need help with diagnosis.

Full disclosure. Years ago the soft top drains blocked, water got into the cabin and the first I knew was when there was so much water I get wet shoes through 1 1/2" foam and carpet. That cost big time for a used (old one was not repairable) security module, and I seem to recall the DME had to be repaird, but I"m not sure now.

So, the misfire starts. As I'd recently done the CPS and MAF, I checked those connections and anything in the vicinity, since I figured maybe I hadn't fully clicked something home and it had now partially come loose. Nope.

I read the codes with my Foxwell knock off Duramtric tool and had:

P0300 - Misfire detected
P1301 - Misfire cyl 1
P1319 - Refer to service manual - emission-relevant cylinder misfire
P1313 - Refer to service manual - Misfire Cylinder 1 (Emission Relevant)

In the past, I think I had DME code 22, which I think is incorrect load from DME to the tiptronic DME. I assumed this was related to the MAF, but I'm mentioning it here for completeness.

So I did the normal things. Swap the coil pack between 1 and 2. Nope, still on cyl 1. I also swapped spark plugs between 1 and 2 just in case. Nope. At the same time, I was obviously checking for moisture anywhere and cleaning things. Nothing.

I have pulled up the carpet under/behing the seat, and there's no moisture or evidence of any having been there. So I don't think it's that. Note. I know the drains are blocked again, possibly permanently, as we have a magnolia tree and those effing leaves have got in there and I can't clear them with air or trying to use stainless steel wire in a drill as a snake - hence I always park it inside... except this once.

So, I need diagnosis help from those who know these brilliant little infuriating pieces of poopoo!