1996LS400

I'm trying to rule out the possibility of water/condensation in my tank as the car sat for close to a year with a pretty empty tank. It's really running rich blowing white smoke and giving random cylinder misfire codes. I put 10 gallons fresh fuel and some water absorber treatment with no luck yet. I plan on letting my 17 year old use it for school and work only because he's a damn good kid.

1996 LS400

Och

iTrader: (3)

Well, you can take off the fuel filter (look on lexls.com for tutorial) and turn the ignition on, but dont start the car. It will pump the fuel out.

Thermactor

iTrader: (1)

your problem is not because of gas, you might have a had a coil die

1996LS400

That sounds like a hell of an idea with the fuel filter! I found the link, it says for 90-94 but I'm sure it will get me close enough. Thanks!!!

1996LS400

It's kind of weird. After I disconnected the batt and it was cold, I started it and no codes even after idling for a few but it still smoked and idled rough. After a min or two I took it around the block and the codes show up. First time it was cylinder misfire 2 & 4. Parked, waited about 10 mins drove around the block again, rescanned and it said cylinders 6 & 8. I tried it again yesterday and only got cylinder misfire on 2. Does this still sound like it could be a coil issue?

PureDrifter

iTrader: (10)

it doesnt sound like it has to do with the fuel itself, more likely clogged injectors or some sort of electronic ignition/ecu issue.

Och

iTrader: (3)

I'd start by draining the fuel, and then filling up 1/2 tank of high octane fuel, and adding a can of good fuel system cleaner, such as BG44K or Techron. Run it through the engine and see where that takes you. If that does not improve things, do a full tune up and check that the timing belt is aligned properly.

Also, to eliminate the possibility of a bad ignition coil, switch them places. If you're getting misfire codes on 2, 4, 6, 8, you will get them on 1, 3, 5, 7 after switching coils, if one of them is bad.