Accord stalls shortly after starting

[wasabi-des]

Hey guys,

I've got a '92 accord with about 330K km's on the clock. A couple of weeks ago I started getting a weird problem when I would go to start the car. It starts up instantly, runs normally for about 15-30 seconds and stalls. As it stalls, it starts running rough and erratic, until it finally stops. If I try to open the throttle at all while the car is running OK for those first 30 seconds, it hesitates to the point of almost stalling before letting the revs climb.

This problem has been driving me insane... So far, this is what I've checked and what I've been able to come up with:

- Distributor contacts cleaned - Contacts had a bit of buildup on them, but no excessive wear or damage.
- Spark plugs replaced - Plugs were in reasonable condition and appeared to have normal wear pattern on them (i.e. not soaked in petrol or oil or carbon), but they were over 40K km old & I decided to change them just to be sure.

None of the above made any difference. The ignition side of things appears to be working OK, though I haven't checked with a timing light yet. Will confirm next weekend.

- Fuel filter replaced - No change

Spent the afternoon playing around with the fuel delivery system. Figured that it might be the fuel filter, as it was ~60K km's old, but made no difference after I replaced it. The fuel system appears to be pressurised (and yes, there is plenty of fuel in the tank ;) ). Next week I'm going to try and get my hands on a fuel pressure gauge and fabricate an adaptor to replace the service bolt on the fuel rail to see if the pressure is dropping off (i.e. suspect fuel pump).

The only other thing I'm going to check is the compression, just to make sure that it isn't a blown head gasket or something. I've noticed that I have been losing a little bit of coolant and no sign of leaks. Also when I drove the car interstate last month, even though I changed the oil before departing, 800km's later the oil was looking more fouled than usual.

I haven't had a look at the electrics just yet, mainly because I don't know where to start. A common problem on this forum of this nature that people get with this gen accord is the ignition switch contact corrosion, but I'm pretty certain this is not the cause in my case. I cleaned the ignition switch a few years ago after it stuffed up and the symptoms were different (i.e. the gauges are all illuminated when the key is in the 'ON' position atm, whereas they had no power when the ignition switch stuffed up).

Now, I'm hoping to draw on the knowledge of this forum... Anyone have any thoughts as to what might be causing the problem? Any ideas would be much appreciated... Am I on the right track?

Thanks for reading my rambling.

Cheers,
- Kei

[Riviera]

is the oil milky??? if so its leaking coolant in there

overheated recently? is so head may have warped...

oil leaking of the bottom side of the head?

my 88 cord had the same problem

[OMG.JAI xD]

resistance in the leads?
timing out?
dirty intake? injectors?
craked piston?
vacuum leak?

just my ideas =]

[wasabi-des]

Thanks for the ideas guys! Got the car going today :D

Bought a multimeter, did the resistance check and found #2 lead was stuffed. Thos still don't know why it ran OK for the first 30 seconds before giving up. New leads are in now and it runs like normal again. It seems like a pretty obvious thing to check now that I think about it... its one of my bad habits to jump to complex conclusions lol.

Riviera, oil is black-ish, but not milky and the only oil leaks I had were around the sump gasket (which is fixed now!). I think its time to change to a thicker oil... Since I haven't overheated it recently, I think its fairly safe to say the head is OK.

Cheers,
- Kei

[Riviera]

thats good news man, hope she pulls another 200k kms more

[JohnL]

Bought a multimeter, did the resistance check and found #2 lead was stuffed. Thos still don't know why it ran OK for the first 30 seconds before giving up.

My theory:

Resistance increases with higher temp, becoming so high that the spark can't jump the gap at the plug. High resistance to start with means more of the energy in the high voltage impulses gets 'absorbed' by the lead and is then radiated as heat, but not radiated fast enough since the conductive parts of the lead are encased in a quite effective insulating layer. If the leads were good then little electrical enregy is 'lost' to heat in the lead and the problem doesn't exist.

The heat and resistance build quite quickly to the point that the lead can no longer conduct enough charge to spark the plug, at which point all the electrical energy must get 'absorbed' further back up the line, most likely in the ignitor (aka ignition control module - ICM) and / or the coil. This can excessively heat up the ignitor and / or coil and can lead to their failure.

Think yourself lucky, high resistance in the leads can cause such damage even if the plugs are still managing to fire. I replaced my ignitor twice before I learned that high lead resistance cooks it.