slow starting

I hope somebody can help me out there. I have a 96 AWD that does a lot of sitting around, the car only has 51,000 miles on it. I can let the car sit for a day, week, or month and it starts up within one or two rotations of the engine. However, once it has warmed up and I shut it off and let it sit anywhere between one hour and eight hours it is harder to start. It always starts, but when it does it sputters a little, smells like fuel, and takes three to four seconds to start versus the instant start if it sits for a day or more and you can see the light blue smoke coming out of the exhaust when this happens. When it starts correctly there is no smoke and the car uses no oil. My local Subaru dealer wanted $300 to trouble shoot the problem because they think it's a fuel injector leaking down into the cylinder and causing it to flood but they couldn't guarantee it's an injector without putting all that labor in it first. Anyway, does it sound like an injector or do you think it could be a O2 sensor or engine map sensor? Anybody out there have a similar problem? I'm open to all suggestions. Keep in mind, I'm not a master mechanic that can get into complex diagnostic work. Thanks for the help.

[gl1674]

All symptoms you describe match those of a leaking fuel injector.
Subies injectors are generally reliable, but sometimes they do leak.
A would definitely not give $300 to a dealer. A new injector is $80,
there is no need to replace all 6 - just a leaking one. You can probably
find a used one much cheaper. There is absolutely no reason to replace
all injectors - such failures are rare and unpredictable. I had one failed at < 100k and remaining 5 worked for another 6 years/75k without any problems

The replacement itself is easy, all you need is a screwdriver to remove two screws on top of fuel injector, disconnect the wire, than you can simply twist
and pull the injector (kinda tricky move), but it is just twist and pool, no
special tools needed.

The hardest part is to find which one is leaking. I did it by pulling the fuel rails
together with injectors and simply watching injector tips for leaks (just a bit of compressed air). I did not have a spare injector on hand and I wanted to be 100% sure it is the injector.
If I had to do it again, I would probably just play a roulette, replacing one injector at a time - removing fuel rails is a pain.

Thanks for the tips on replacing the fuel injectors. When you twist the injector to take it out does it matter which way you twist? Are they difficult to reinstall? Thanks again for the help.

[immortal_suby]

you can twist the injector in any direction. They are easy to reinstall.

Well, I finally got the injectors out, which I must say was a pain in the butt:-)
When I pulled the injectors out a fair amount a fuel ran down the intake runners. Will this be a problem when I go to restart the car after replacing the bad injector or injectors? After I've reinstalled everything, will I need to prime the fuel system or simply start the car? Thanks for everyones help.

[oab_au]

Originally Posted by coop493

Well, I finally got the injectors out, which I must say was a pain in the butt:-)
When I pulled the injectors out a fair amount a fuel ran down the intake runners. Will this be a problem when I go to restart the car after replacing the bad injector or injectors? After I've reinstalled everything, will I need to prime the fuel system or simply start the car? Thanks for everyones help.

The extra fuel may make it a bit slow to start, but you have had that happening for a while, no problem. The injectors will bleed out when you start it up, don't need to do anything else.
While the injectors are out, you could try putting a bit of compressed air (less than 40psi) to each, to see if you can locate the leaking one.

Harvey.

[gl1674]

Originally Posted by coop493

When I pulled the injectors out a fair amount a fuel ran down the intake runners. Will this be a problem when I go to restart the car after replacing the bad injector or injectors?

It will not be a big problem, especially if you let it sit overnight. As Harvey said, you might get a difficult start due to over-rich condition. Before you crank, floor the accelerator and keep it floored while you crank until the engine catches. It is a special flood clearing mode programed in the ECU, it will take ~5 seconds of cranking, but if your battery is any good it will just start after that.

You probably will not need this flood clearing mode for a cold start, but just in case.

There is no need to prime fuel system - it will purge itself, just give it a couple of seconds with ignition on before cranking, you might even hear bubbles in the fuel tank.

I finally got a new set of Python Injectors and installed them, twice. The first time I must have had one with a pinched O Ring because it acted like it had a miss at low RPM. THis is where the problem comes in. I took them out last night and, as before, a lot of fuel ran down the intake runners. This afternoon I reinstalled them and went to crank up the car and it made half a rotation and locked up! Too much fuel in the cylinders I imagine. I think they refer to this as hydrostatic lock-up. Lucky me My question is...if I wait a day or two will the pressure reduce, gas pushes by the piston rings, enough to start the car or will I have to take out the plugs? If I ever get this thing started again I will have the oil changed quickly. Thanks for any help you guys can provide.