thespen

Here's an odd one for you guys.
My car has had no trouble starting up until recently, like the past few weeks.
I drive it to work a couple days a week usually. It starts up fine in the morning when I leave, and if I stop it hot starts fine as well.
The problem seems to occur when I leave work after it's been sitting for ~9 hours. I've gone out to leave, and the car cranks over excessively. I suppose I noticed the long crank a while ago but didn't think much of it as it wasn't overly long. It's been progressively getting longer to the point that today I thought my battery was going to die before it started.
There doesn't seem to be an air obstruction and it appears to be getting spark. The only thing left would be that it's flooding.
I have some more troubleshooting to do yet obviously but I won't have time until the weekend. I figured I'd see if anyone has encountered this before though.

Basically, what could be causing a starting issue when cold, that clears up overnight?
Failing injectors that leak while warm?

Any suggestions are appreciated, thanks guys.

SpikeDerailed

iTrader: (7)

When it comes to starting issues the first two things i usually check on a rotary is compression and the main coolant temp sensor.

diabolical1

iTrader: (3)

welcome to the board.

my first thoughts are:

maybe leaking injectors?

how many miles on the current plugs?

thespen

Thanks for the welcome, I joined up ages ago but I guess I've been too busy with other projects to be much of an active memeber here. We'll see if I can fix that lol.

I plan to do a comp test next week when I get the time. I doubt that's the issue though given it starts fine any time hot or cold except after it's been sitting for long enough to cool down but not overnight.
The temp sensor appears to be fine, I've had no trouble coolant wise so far.

I'm going to pull the manifold and send the injectors out for cleaning/testing if the comp test is fine and I do find it's been flooding. Will do the plugs as they're getting on 50k I'd imagine. I put them in when I got the car and paid for Denso iridium. I doubt that's the root of the problem either, but it may not help.

I have a few non-rotary friends telling me to try a redline fuel system cleaner or the like first. I think that would just be a stop gap though and not totally fix the issue. I'm of the mind proper preventative maintenance is worth the time rather than just pushing the issue down the line. If it's a damaged injector then the flush won't help and I'm likely to kill my battery one of these days.

I wouldn't mind taking a look at the OMP and vacuum lines while I'm in there as well. I think there may be a small vacuum leak somewhere which would be nice to address. If I do get it all apart I hear the pulsation damper is worth taking a look at as well, although mine seems to be fine for the moment...