- Sat Jun 09, 2007 3:24 pm
#10455
I had an idea.....
So my car started last week and ran rough for a min (brand new motor) and then smoothed out for a few mins. This was with the old bad battery, I had jumper cables going to my hx the whole time.
So I figured the bad battery had been charged after a few mins, so I took off the jumper cables. About a min later, the car started to idle crappy and then eventually died in another min or so (just like it still does).
I've replaced everything, and it's still doing this and every time I pull the plugs out they are covered in soot. Like the car must be either running way to rich or not getting spark. Well I know that it is getting spark because I've put in brand new plugs, and tried diffeent dizzy & wires.
So here's my latest guess... When it was idling smooth the first night it ran, the battery started to die when i unhooked the jumper cables. The weak battery gave a weaker spark, which burned less fuel. The plugs became fouled along with the dying battery... there was probably very little spark by the time the battery died and the car stalled. Perhaps when this happened, it was so rich that it could have fouled the O2 sensor or got enough soot in it so that now it isn't able to read correctly (but not damaged enough to throw a CEL). I cleaned it off with a wire brush once, but maybe that wasn't good enough.
So maybe it is not able to get an accurate reading of the oxygen, so it thinks that it needs to tell the ECU to dump in more fuel. This is like the snowball effect because it's running richer, fowling the plugs faster, and then getting the same soot all over the o2 sensor, which would make it read even worse, causing the ecu do dump more gas in to try to keep the car running.
I've got nothing else left to try.... might as well give it a shot
So my car started last week and ran rough for a min (brand new motor) and then smoothed out for a few mins. This was with the old bad battery, I had jumper cables going to my hx the whole time.
So I figured the bad battery had been charged after a few mins, so I took off the jumper cables. About a min later, the car started to idle crappy and then eventually died in another min or so (just like it still does).
I've replaced everything, and it's still doing this and every time I pull the plugs out they are covered in soot. Like the car must be either running way to rich or not getting spark. Well I know that it is getting spark because I've put in brand new plugs, and tried diffeent dizzy & wires.
So here's my latest guess... When it was idling smooth the first night it ran, the battery started to die when i unhooked the jumper cables. The weak battery gave a weaker spark, which burned less fuel. The plugs became fouled along with the dying battery... there was probably very little spark by the time the battery died and the car stalled. Perhaps when this happened, it was so rich that it could have fouled the O2 sensor or got enough soot in it so that now it isn't able to read correctly (but not damaged enough to throw a CEL). I cleaned it off with a wire brush once, but maybe that wasn't good enough.
So maybe it is not able to get an accurate reading of the oxygen, so it thinks that it needs to tell the ECU to dump in more fuel. This is like the snowball effect because it's running richer, fowling the plugs faster, and then getting the same soot all over the o2 sensor, which would make it read even worse, causing the ecu do dump more gas in to try to keep the car running.
I've got nothing else left to try.... might as well give it a shot
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My 1992 SOHC Turbo Hatch
My Youtube Channel: 6th Gear Garage
My 1992 SOHC Turbo Hatch
My Youtube Channel: 6th Gear Garage