1990 Honda accord ex manual
F22a jdm engine

H22 lower intake manifold
F22 upper intake Plenum
F22 fitv and iac
Iabs butterfly's removed and sealed

OK got rid of a bouncing idle after switching back to the f22 Plenum. The car runs perfect. No idle problems when driving and no idle bounce. The only issue it has is when starting up while the engine has been sitting over night or all day. At startup the engine idles low around 1000-1100rpms and kinda rough for about 20-30 seconds then it goes up to 1500 where it should be at cold idle. Also goes down to regular idle slowly just like it should. Coolant has been bled several times to make sure all the air is gone.

Anyone got anymore ideas on where I should go next. I installed this engine myself and built everything around it from extra parts from 3 different engines. This is the last issue I have and I would love to get it figured out before the cold weather arrives. Thanks in advance

 

could just be a sticking fitv...over time they get corroded and get carbon deposits

 

Already been removed cleaned and screwed the plastic part all the way back in. Just did a full tune up, plugs wires cap rotor. Thinking maybe fuel may be the problem but where do I start

 

put it back stock and see what happens

 

but i didnt got this manual any time before, why is this so? can i get any manual for this a help would be appreciated a lot....

 

I've attempted going back to the stock intake manifold with only 4 intake holes and in Plenum and no spacer. If course using almost all the same parts except the upper and lower manifold. I still get the same result

 

The car as always had this problem since I bought it 3 years ago. It came with an f22a4 and was all stock. replaced with a jdm f22a and a f22a6 ecu. I've replaced almost every part on the car mostly with new OEM replacements and a few junkyard parts.

To better describe what its doing when the engine is bone cold especially in cold weather idle kinda fluctuates around 900-1000 almost like it wants to die then after a little it goes up to to 1500 rpms until it gets hot hen slowly goes back down to 750. It also has a small idle surge but only when midrange to high driving revs when still cold goes away as quick as it starts. Going to try and source another fitv.


Anyway that startup solenoid that lets air in during startup could be malfunctioning and causing this. I don't really know anything about these things or their real purpose.

 

the air boost valve simply allows extra air at startup...the f22a's normally come with a blockoff plate...you can test the valve by simply sticking a vacuum pump on it and seeing if it holds...just give it like 3 inches of vacuum

Why are you using the a6 ecu ? That ecu uses butterflies. Use your A4 and like I said, put it completely back to stock. There's no point whatsoever using different intake parts without some sort of tune.

After doing the things I suggested, I would warm the car up completely and then adjust the base idle...or atleast check it.

 

Well its an f22a came with the butterflies. using that ecu because a little ghost told me the cams would.work more efficiently. My harness however is still the f22a4 harness. No Iab hook ups. I don't see how the Iabs would effect idle with the engine cold since after it runs for 30 seconds it cold idles perfect with the iab disabled. Are there any other parts like the maf or fpr that could cause this cold idle. Going to go source an extra fitv from he junk yard and see if anything changes as soon as my back gets in better shape.

Ill probably go ahead and source a f22a4 ecu also and see if that fixes it.