galdo12

I have a full B16 in a eg hatchback. year 94. I have had many small problems with it just like this, easy to fix but hard to diagnose.

So the problem is: when I barely press/ tap the gas and hold it, it surges. Like if the pedal is pressed 5-10 millimeters in. It is not a high high surge, but it is noticeable and affects performance of the car. I cannot move from a complete stop smoothly, I have to rev up to 2-3000 rpm.

A problem before this was that it was idling too high. The screw did nothing to change it. I cleaned and tightened the FIAC and that fixed it but it still surges when barely pressing/tap the gas.

Any thoughts? Help?

galdo12

Any help would be appreciated

speedjunkie_g35

Check for vacuum leaks?

galdo12

yes. It was leaking where the pipe connects to the throttle body at the bottom. I sprayed card cleaner and the idle dropped then came back up. But it was leaking from before and the surging was not present. I changed the gasket for the throttle body but it is still surging.

Syndacate

It's possible that the hole in your intake was there, and not very big...then it split more and now it's big.

Remove the vacuum leak and see if the problem persists.

Dustin B

I know this is an old post but I'm having the same issue, What was the cause? I do have a couple vacuum leaks to work out

Dustin B

just from the fitv I believe

Syndacate

Really sounds like vacuum leak symptoms...try resolving those first, IMO.

88CRX_SiR

As above, vacuum leaks first, they always need to fixed pronto.

Second, make sure you don't have your throttle cable too tight.

Dustin B

I will knock out the leaks tomorrow hopefully. and throttle cable and tps are properly adjusted. Thanks for the help guys! this has been the strangest thing iv ever encountered. all other comments and advice are welcome!

Dustin B

has anyone experienced this with a bad iacv? it's a fresh swap I have no idea if the iacv is good. I'm getting code 14

Syndacate

Google around 'testing resistance iacv' or similar to test IACV electronics. If resistance is in range and it's clean and no vacuum leaks it should be fine.

Dustin B

thanks for the advice I'll look into it more, iv also seen tests where you can unplug it and see if idle raises, or to give it a12v signal to see if the valve closes completely

Syndacate

Yeah, if it's an actuator that makes sense. I haven't tried that personally and don't have my civic anymore.

tony_2018

The only pipes I'm aware of that are under the throttle body are for the coolant lines that run to the IACV, on obd1 its the FITV and than to the IACV.

Dustin B

yeah I blocked off the fitv but it still boggs if I shoot the mating surface with brake clean, so it's just not blocked off well I suppose. before the block off it surged at idle. the coolant line is bypassed straight from the head to the iacv

Dustin B

swapped tb gasket and blocked the fitv with gasket material and somethin similar to rtv, still surged at allitle throttle, swapped ecus for a gsr basemap with deleted iab and it stopped, only problem is when driving it around it has absolutely no power. what dyou guys think?? I also have no o2s hooked up. All help is appreciated!

Syndacate

You're changing too many things at once. Try to narrow it down by changing one variable at a time.

IAB removal wouldn't cause it.

I'm not sure what you had on there before but if it was a standalone and a crappy tune that could have done it.

Dustin B

agreed I changed too much haha. but it was good to find out my tune wasn't good for the motor, however the tune worked okay with my friends gsr. which raises the question of weather my car is still screwed up or if the tune just didn't match well to my set up.. I don't know what the gsr base has different besides more fuel output, but I had perfect throttle response just off idle. does the iab delete affect the iacv? after plugging and unplugging the iacv, the car would hold around 3k idle with it plugged in. thanks for the help

Dustin B

and my ecu is a chipped p28 from eBay,it's partially customized as far as vtec engagement and redline and some other little things

Syndacate

Why are you running GSR basemaps? A B16 basemap will be closer.

What was set on the chipped P28, a GSR map?

tony_2018

Where the hell do these guys be getting the idea to run different basemaps with different engines? I don't get this ****......

Norlael

since you said you sprayed with brake cleaner to check for leaks on the manifold, I would suggest for you to now check the engine timing and valve lash

Syndacate

I couldn't agree more. People have been doing that for YEARS in the [bad] theory of pushing out more power. I'm not sure if this was that or just B16 ECU availability or something.

Dustin B

it was the closest ecu I could try with. my original single cam ecu does the surging too. I'm guessing it's possibly fuel related?