I have a problem which bothers me almost for a year. I have no clue what to do with this. Maybe someone will have an idea.
I start a car (engine completely cold), rpms go up to 1600 which, I consider, is normal. After a minute rpms start to drop and very quickly hit 800-1000. Then the car starts to shake and choke. Of course rpms are bouncing from 800 to 1300 (one bar appears on the coolant gauge at this time). In that moment when I stop at crossroads the rpms drop almost to zero and engine stalls. Sometimes ECU is able to bump them just before engine dies and it's a big choke... The problem seems to disappear when engine is warmed up (two bars on the gauge), but you can feel some hesitation while idling (rpms bounce a bit).
What's more: when I turn off the engine and let it cool down a bit (one bar on the gauge) and start it again, it starts to detonate in my cat and you can feel like something holds the car (rpms rise and the car is not going to accelerate at all). After a while it jumps forward like someone kicked it...

I changed all the ignition stuff (wires, rotor, coil, ICM, plugs, cap). All filters are fresh. No vacuum leak in the manifold area. Clean TB, IAC, fast thermo. I had a faulty coolant temperature sensor before so I replaced it with used one from H23 (it was fully operable in that engine). I resoldered all the connections in the main relay, checked fuel pressure.
Now I'm stuck... Have no idea what could cause such a behavior.
Help
pentaq

 

i have the same problem...im also out of ideas

 

did you check ALL possible vacuum lines for leaks?

 

maybe its sumthin with the fuel pump? im goin to change mine cuz my car does the same thing but not all the time.

 

no leaks, fuel pressure normal.

today I couldn't drive at all. Even after warm up the engine kept dying at every stop

 

When the engine dies do you still hear the fuel pump running?!

And when you did ignition changes did you replace the ICM completely. Bad contacts on the ignitor are known to cause this problem..

 

hmm no, pump stops with engine. I'm sure ICM is put properly. I checked twice before the dizzy assembly.
I went to dealership today and they say that my O2 sensor is stuck at 0.92V (terribly rich I suppose) while idling. So I wonder if this is the effect of something wrong in the engine or it causes all that evil.

pentaq