Thanks for the tips.
I have scan tool. Got it from
http://obd-2.com. I can get datastream and it draws some digrams, but I do not know what parameters to monitor and how to interpret them. Could you tip me on those?
Last tune-up was in May last year but I'm not sure what exactly was done then. About a month ago my car stalled after starting from a red light, I think when it switched to second gear. The engine was still cold and it wouldn't start for a few minutes. I released the fuel pressure from the test port and the car started after a couple seconds but would run close to stalling on idle. I checked the spark plugs the next day and found 4 and 6 with gap 0.6, it should be 0.42-0.46 on my car. Those two plugs smelled like gasoline and looked wet. I cleaned all plugs and gapped them. I have used anti-seize on the plugs and dielectric on the wires before. My mechanic yelled at me for using anti-seize on this type of engine - aluminum block, although Haynes manual say do so.
The car ran perfectly for awhile, I guess until the computer got retrained. If I reset the computer the engine will run fine and within 20 miles it will get back to the same.
Yesterday I had 40 miles trip and after the 10 miles the car will run much better. Still has problem when driving down-hill with trottle almost close.
I did vacuum test yesterday. It holds fairly steady on 17 psi. It trembles a little but no more than quarter psi from 17. On quick press/release of the gas pedal the pressure jumps to zero then jumps to about 22 and then slowly in about three seconds back to 17. I think that's what it should do.
I also dosconnected the electrical connector of the idle contol valve and started the engine - big difference, so it must be working.
If I turn the AC on/off the RPMs go down/up with about 100.
Today I will change air filter, fuel filter, PCV valve and grommet (the PCV valve doesn't fit tight in the grommet), will do an oil change and put some injector cleaner. I may put some oil treatment too.
Next week will clean the throttle body if there is no improvement.