Rep Power: 0

Civic info:
1998 Honda Civic Ex Coupe 2 door
D16Y8 engine, 1.6L SOHC Vtec 4 Cylinder Automatic

The idle fluctuates a little bit after start, idling as high as 2.5k rpms and as low as it will go, try to die, then rise back up fast by it's self. It will do it 4 times at least, and starts to settle down at a medium where it rests just at or a little below 1k rpms.

Sometimes it will do the same thing, but instead of starting fluidly, it will hesitate it's self in start, jolting/rumbling, sounding just like it does when it idles real low in it's fluctuating idle, then it rises to 2.5k rpms, and about 10 seconds later it will do the fluctuating idle.

It will also power down or "Bog" for a few blocks unless I slam on the gas, which I don't. It used to only do this bogging twice and only 100 feet after driving, then abruptly ending and would not show it's self again. The bogging is a given that will happen no matter what the car does at start.

Sometimes the gears will switch oddly, and all I can relate the sound to is using clutch on manual, revving down a little, like it's not engaging right onto the next gear up like an automatic transmission is supposed to, or at least what I am used to. I am sure the torque converter is fine. I am sure the torque converter solenoids are fine. Why? Because it does not happen when I reset the ecu. It happens after I have turned off the car and started to drive again, just like the other problems were and still are.

Out of all of this, there hasn't been a check engine light for any of it. The only reasons why the IACV was replaced was that I had a hunch, and the mechanic that looked at it plugged in his computer, tested the idle or something, and then
a check engine light appeared. Miraculous. I'm not phased.


Parts replaced so far (within 2 weeks) from first to last:



Fuel filter
Battery
Cap and rotor
Fuel pressure regulator
Starter (Duralast)
Alternator (New, Not reman, NAPA)
Power and ground wires (4 gauge, copper, copper connectors, solid connections)
TPS (Throttle position sensor)
Spark plugs (double platinum, laser something)
Spark plug wires (NGK)
IACV (Idle air control valve, from honda)

Others 1 month before:

Head gasket (MLS Gates and resurfaced head)
Radiator, hoses, 172 degree oem thermostat, heat sensor and relay
70/30 coolant mixture. Fan turns on.

Oil is level and new, 10w30. Transmission fluid is level.

 
Rep Power: 0

I am having a very similar issue, but i think mine is in a further stage..
I start my car, and 3-5 minutes later, it starts to sputter and act like its starving for gas, as if I let off the gas. I can just tap the gas repeatedly, and the throttle will temporarily work, (in spurts), but if i hold the petal, it acts as if im letting go of the petal, and it sputters really bad. if i mash the petal down, i get one of two things, very horrible sounds (so i dont do this anymore.. learned the first time) or if i time it right, i get it to go with the higher RPM and it acts fine for a second, then gors back to the problem. and it acts like this until i pull over and let it idle and go through a little sputter fit, and then its fine... until i hit a bump, stop for a sign, or red light, then when i go again, it does it again. its really freaking me out, makes me wonder if I'm going to make it to work everyday.

I have seen many issues on these forums that are almost similar, but not quite what i am experiencing. I've read peoples posts saying everything from change the plugs/wires/distributor, to vacuum leaks, to air filter, to fuel pump/filter/injectors, to sensors, to fuses, to head gasket. and I really just dont have the money to go down the whole list, especially if i do it in the wrong order, and fix it on the last one!

I have replaced the fuel filter, air filter, and run injector cleaner through it several times, got new plugs, and it hasnt been too terribly long since i had gotten a new head gasket