93 Accord cranks but won't start unless it's sat for a while
I have a '93 Accord with an unusual problem. First thing in the morning, the thing starts
fine. Same with when I'm leaving work at the end of the day. However, If I try to start the
car 1-3h after it's been turned off, it'll crank and turn over, but not catch.
It's usually okay while driving, but sometimes after a difficult start just seems to turn
itself off. No struggle or surging, just off. Zero rpm while in 3rd, driving down the road.
This usually only happens like 5-10min into the drive and it's sometimes difficult to start
again, usually producing a nice cloud of white/ grey smoke when it does.
When it doesn't want to catch, I can usually eventually make it. If I just hammer on the
starter intermittently, it eventually starts up really weak and muddy sounding, at one
point sounding like only a single spark plug was firing, then another, then all four. I've
also been taking out the key and putting it back in for a short crank, which seems to
work better and eventually results in a nice clean start on one of the tries (usually like
the 15th or so). First time this happened, I just took the key out, put it back in the
other way and then it started no problem, which I think is sorta weird, looking back.
At first I was worried about the fuel filter/ pump. Changed the filter and it runs smoother
now when it is running, but no change on the no-starts. In one instance, the car wasn't
starting and I wanted to see if the pump was working right then and there, so I undid
the fuel rail bolt and when I (briefly) tried to start it, fuel went everywhere like a geyser,
so I'm convinced the pump is working okay.
The battery's strong (tested) and getting a boost doesn't seem to help. Now I'm
wondering if I'm getting a spark. I did see one off a plug wire this morning, but the car
always starts in the morning. I'll update on the spark situation when I get another
difficult start experience.
In the mean time, does anyone have any idea what could be the problem or what
diagnostics I could do? The fact that it seems to start and run fine after sitting for 4+
hours or less than like 30min is more than a little confusing to me.
