I'm having issues with idle surge still on my d15 non vtec.. Here are the steps I've taken:

Full tune up, plugs, wires, cap, rotor, fuel filter, sea foam, throttle body clean, idle air control clean, fast idle thermo valve clean. (used to idle at 3k and bounce from 1500 to 2000 rpm, now it idles fine but bounces from 1400 to 1800 sometimes).

I've bled the cooling system too, but I do have a question on that.. My car has no heater core or anything like that, all related components for having heat are removed from the car, so I can't bleed it with the heat on. Shouldn't matter I don't think though?

What else could this be? Vacuum leak? Only codes I was getting was o2 sensor but I fixed that, and an auto trans lockup valve code but my car is 5 speed, so that code is null.

Also, once the car has been running about 5-10 minutes, the car will sputter under a load. I can rev it all day in neutral or clutch in, no problem. Once I take off in the lower RPM it sputters real bad sounds like a machine gun sometimes hah, then it will clear up till I hit the next gear. This is very aggravating.. I think maybe ignition timing, but I can't check cause I don't have a lower timing cover.... >:[

Any ideas?

 

Have you adjusted the ignition timing to spec using a timing gun? Edit - Get lower and upper timing belt covers.

How are the heater hoses now arranged? Post pictures.

When the engine is warm and the idle is hunting, pull off the air intake system and then use your finger to cover the hole leading either to the IACV or FITV. Does covering one of these holes make the idle settle down? When you do this test, there should be no suction from the FITV hole.

There's apparently a way to convert your auto ECU to manual.

 

I'll have to take pics tomorrow, I believe the heater hose goes from the block to the head right away, and I'll definitely try that test asap. As for the timing covers, I'm just going to wait off for that I suppose. Honda wants 90$ for the lower cover and I don't feel like removing the crank bolt on this damn motor haha, hopefully this motor isn't in the car much longer anyway, just wanted to see if there was any other ideas

Oh, and any info on that ECU conversion?

 

Bite the bullet and get some covers from a junk yard -- they are very important.

 

94EG8 has mentioned this, but other members may also know how to do it.

 

Alright thanks man, thanks for all the help recently.