so, my v6 isnt playing ball, wont start up at all.

it has gone like this in the space of a day, we had it nose up on ramps to have a look under and paint around the battery area and make a clamp for it. left it a day for the paint to dry, plus it was pouring rain all day. put battery back in and go to start it day after and it was running terrible, wouldnt idle, needed throttle to keep alive and sounded like a bag o nails. next day it wouldnt start at all, just keeps turning over coughing.
no codes, good spark, dizzy cap looks alright, fuel pump working, tried different ecm, different ignition coil, no change any ideas?
i dunno whats left to consider, dodgy ignition module? timing chain?

 

I'm thinking MAF. They are pretty notorious for failing out of the blue. Same with the ignition module.

I have had your exact problem, but it actually WAS the ignition coil. I thought everything was fine, had great spark when I checked, and didn't get it. Then I kept working on it after dark and we noticed that it failed in a peculiar way. When you pulled a spark plug cable and tested the spark it was fine; when you had all the plug wires on and cranked it we could see the spark jumping from the main body of the coil to the coil mount bracket and shorting out.

On old forklifts we used to call this misfire under compression only. Switching to delco plugs helped a lot, versus champion. I replaced the coil AND PROPERLY MOUNTED IT TO THE BRACKET and then the car started right up.

I also had a similar problem with my 90 V6 after I changed the alternator. It shorted after a rain and sent a voltage spike somewhere and fried my injectors. I went to the wrecking yard and pulled a used set and I was back on the road.

Especially because of the rain and the age of your car, check all efi connectors under the hood, mainly the big one on the front driver's side of the engine where the injector harness plugs in.

Good luck!