Hi, I recently bought a 93 civic with a B16 swap, running into trouble when cold starting. engine will crank but not start until I give it gas then doesn't want to stay running unless it hits 2000 rpm then seems to idle fine and will restart fine once warmed up. dunno what the problem could be injectors are all good no vacuum leaks i can find kinda at a loss here any ideas??

 

Could be about a dozen things. I would start my diagnoses at the IACV. Do a search for IACV cleaning and you should find some good info.

 

Does the engine have an FITV?

 

IACV seems to be working and is clean. Not sure what the FITV is, how to tell?

 

Is it a stock B16a2?

Any CEL codes?

If you have one, the FITV is usually mounted below the throttle body.

 

Thanks for the quick responses, yeah FITV is there or at least a coolant hose goes to there and then to the IACV. As far as I know the engine is stock aside from exhaust and cold air intake. very low idle if that helps. No CEl either..

 

Did you remove the IACV and make sure it was clean? I would recommend you download the Service Manual and look up the step by step instructions for "Hard to Start". It's hard for us to diagnose without having the car in front of us.

 

Yeah It was the first thing I tried. Doesn't seem like a very common problem, hard to find info on. I have a working IACV for an F22 think I should just try to switch them or do you know if they are interchangeable?

 

Actually it is a very common problem.

https://honda-tech.com/forums/acura-integra-6/%2A%2A%2Ahow-clean%2A%2A%2A-your-iacv-k-idle-air-control-valve-1575913/

I doubt they are interchangeable.

 

Oh yeah the IAVC must be I just meant the overall symptoms that the car has
Of course not, that would be too easy.. wishful thinking lol. maybe try to clean it again I guess. The more I look I don't see anything that looks like the FITV maybe it doesn't have one? change anything if not?

 

Post pictures.

 

It does. There is an easy way to diagnose this, and than there is a not so easy to diagnose this.

1) remove your intake piping from the throttle body.
2) look inside the throttle body. you will see 2 holes inside the throttle body. The top hole is for your IACV. The bottom hole is for your FITV.
3) with the engine running, place your finger over the IACV hole.
If your idle corrects itself than your IACV is your problem.

4) put your finger over the FITV hole. Again, if the idle corrects itself, than the FITV is at fault. It most likely isnt broken, but probably just unthreaded itself due to vibration.

IF its the FITV, it sits just below the throttle body and has only 2 coolant lines. One in, and one out. When you remove the coolant lines, be sure to have some vise grips ready to close off the hose from antifreeze leaking all over the place. From there, you can remove the FITV housing by removing the three bolts (10mm) if i remember correctly. once you remove the housing from the manifold, there is a brass plate on the bottom of the housing that has 2 philips head screws holding it on. remove them and take the plate off. From there, you can see the plunger inside of the FITV housing. Most likely, it is loose and moving around inside. You will have to press the plunger back in firmly and turn to thread it back on. Once it is in as tight as you can get it with your hands, take a flat-head screwdriver and place the tip in the groove on the white ring around the plunger and turn it as if you were tightening it. That will make it secure for use.

Put it all back together, apply coolant lines and then start it up and see if your idle is fixed. If the problem was the FITV and it was as i descibed than i can almost guarantee your idle issue will be corrected.

If it isnt either the IACV or the FITV than look for vacuum lines on the back of the intake manifold for leaks, torn hoses or just plain open lines (not plugged or connected).

If this still doesnt fix your idle problem, try flushing your radiator and replace with fresh coolant. Make sure you do this correctly or else you will not get the results you want, just more headaches. Always replace thermostat when doing a rad flush.