DanielSLe

So my car throws CEL codes 14 and 21 - IACV (Idle air control valve) and Vtec. I have a b16a2 in my 92 hatchback and it worked like a charm up until I rebuilt it. Then, my idle started surging between 1500 and 1700 and no vtec. I replaced my vtec silenoid and i now have vtec back but it still throws code 21. As for my idle problem, I've replaced my IACV with another IACV, replaced my fuel pumps and fuel filters. I looked for vacuum leaks and flushed the radiator.

Now when I drive, it drives fine except when i release the gas. When I do, the car jerks back like im down shifting, and when i barely press the gas again it jumps forward. Pretty much, I can't stay at a constant speed, it's always slowly accelerating so i have to release the gas and press it again on the highway constantly. I thought it was the throttle body at that point, so i covered the tb with my palm and it stalls of course. I replaced my map sensor, and have a new tps sensor but i didnt put it in yet.

When i take off my tps sensor, the car stutters then idles a little lower, more regularly, but i try to drive and it wont pass 2000 rpms. I'm not familiar with calibrating my new tps sensor, but my CEL doesnt say TPS sensor so i didnt figure its the problem.

ALSO, when i put in another ecu, i have to constant hold the gas for it to stay on, otherwise it'll just die.

So what im asking is:

-Why does my CEL still throw vtec code when it works now?
-Why is my car idling like that?
-Why does my car accelerate like that?
-Why can't i use another ecu?

Thanks for any help guys!

Extra: I've got a missing sensor i think its the BARO sensor. I have one vacuum connecting to the firewall, and one vacuum connecting to my manifold. The only question is where do i find the sensor? It's been unplugged and i cant find it anywhere.



the bottom vacuum is hooked up to my manifold here

canadaek

that looks like the purge solenoid and make sure you cap off any ports your not using
use a dvom to set your tps sensor.
what Ecu are you using ?
maybe your counting the flashes wrong if you have a vtec code it shouldn't work.

DanielSLe

I'm not too sure what you mean by capping off ports i dont need, could you simplify that for me?

Also I have in my car right now a chipped p28, and i used another chipped p28 before i rebuilt it now. I cant put that one back in or the problem will happen. I tried using a few other ecus and does the same thing.

And the flashes are correct. 2 long flashes and 1 quick blink.

canadaek

the vacum ports make sure none of them are open (leaking) is your throttle cable to tight ?

DanielSLe

Yes it's tight and i have no leaks.

davascript

Have you tried to clean the IACV Valves? Use brake/carb cleaner and let it dry for a while. Its possible that you have two gummed up IACV's.

DanielSLe

So I cleaned boh IACV's and let them dry, put them in and did the same thing. I also took the IACV from my cousins EK and put it in mine, nothing happened- his car ran perfectly fine with mine in his. (Also did the same thing with map sensor). I put in another chipped p28 to see if it would work and nothing. I still had to hold the gas to keep the car on.

So in light of holding the gas, we figured we could tighted the throttle cable to constantly hold the idle. We turned the car on and held on the gas around a 800 rpm idle, compared to the 1500-2000 surge. Then tightened the throttle cable so where it would stay constant. After doing so it idled perfectly fine until i gave it a little gas and if i were to stay at 1500 rpms, it surged again. So i temporarilly MASKED the idle problem. As for driving, i still cant stay at a constant speed, but it doesnt jerk as much, i wondered how it would effect my vtec so i punched it. I guess i punched it too hard because i think the throttle cable loosened again and the idle died. Had to hold the gas to idle all the way home.

Still any ideas of what it could be? Not throwing vtec code anymore, i guess it went away with time, but still throwing IACV. I still dont understand my problem.

Replaced Idle Air Control Valve √
Replace Map Sensor √
Flush Radiator √
Checked for vacuum leaks √
Checked gaskets √
Replaced ECU √
Replaced Fuel Pump √
Checked throttle body √
Replaced TPS X
Found out about this BARO sensor X

Anything im missing? I'm completely boggled when it comes down to it, running out of options :X

EE_Chris

What was rebuilt?

DanielSLe

The head was rebuilt and polished.

canadaek

have you checked the timing ? maybe do a compression check.

acake em1

this isnt related really, but at one point i had the jerking problem you are referring to, and i was out of options. i found that i had a bad valve cover gasket. i replaced that and my car didnt jerk anymore. check your plugs and see if they are oily. probably not the issue, but who knows. otherwise i notice you replaced the tps, but did u calibrate it yet?

collin-eg2

Sounds like your throttle cable is too tight and is actually keeping the throttle a little open. The service manual says you should be able to push the cable down with your finger 10mm before the throttle body opens

EE_Chris

You have a vacuum leak. As a result, it's causing the idle to raise and kick-in the 'fuel-cut-on-decel' strategy that the ECU uses to save fuel. Also as a result of the vacuum leak is a raised idle that the IACV can't control. And if the IACV can't control the idle, the ECU wants to blame something, so you get a Code 14.

If your car was perfectly fine before taking off the head, then it stands to reason that the problem probably has something to do with it, or its re-installation.

DanielSLe

@canadaek: I did the timing myself, I usually do and it's most always perfect. But I felt like i needed a professional to do it this time so i took it to redline and had them do my timing for me. It's timed perfect now. As far as compression, no i havent touched that yet.

@acake em1: I got a new valve cover gasket about 6000 miles ago. :X I'm not sure on how long they're supposed to last and how often im to change it out. But i did check my spark plugs and they're fine. But i actually havent done TPS yet. My volt meter is broken or maybe just out of batteries.

@collin-eg2: I checked the throttle body screw thingy, it is pretty tight, I can't loosen it though due to an old and stripped screw.

@EE_Chris: I did check for vacuum leaks and thought i didnt have any. Luckily for me, I had someone turn off my car for me while i was at the engine bay, and i did hear some sucking in like i did have a leak. So i need to re check for leaks again. But my friends and I were testing out new ECU's on my car, and when i put in a prelude's H22 ecu in and vtec'd I blew one of my radiator hoses! Small leak and i already have hose to put in today. But good explanation. I'll look for new leaks today.

cruizinmax

iTrader: (2)

The solenoid your holding is the evap purge solenoid. Was it plugged in before? Does the car idle any better if you unhook the vacuum line to that solenoid and plug the nipple on the manifold?

DanielSLe

I dont recall if it was or wasnt plugged in before. But no, it makes no difference if i hook it up or dont. Do you happen to know where i can find the plug? Is it on my firewall, or my wire harness? I've looked everywhere on the internet and forums and no one seems to know where i can find it, or if i even need it at all.

ekphil

I had the same problem on my b16 i had done everything that you have I found out that it was a vacuum leak you can spray carb cleaner on the lines and if it revs up you found it also check intake manifold gaskets.

DanielSLe

I'll look for the vacuum leak tomorrow. Glee premiers today i cant miss it! Haha.

But would the carb cleaner hurt the engine if it pulls through the vacuum line?

ekphil

Use starting fluid it works sorry i dont know why i put carb cleaner

cruizinmax

iTrader: (2)

No, it's made to go through the engine. Won't hurt anything.

Snowman2729

[QUOTE=DanielSLe;43568318]So my car throws CEL codes 14 and 21 - IACV (Idle air control valve) and Vtec. I have a b16a2 in my 92 hatchback and it worked like a charm up until I rebuilt it. Then, my idle started surging between 1500 and 1700 and no vtec. I replaced my vtec silenoid and i now have vtec back but it still throws code 21. As for my idle problem, I've replaced my IACV with another IACV, replaced my fuel pumps and fuel filters. I looked for vacuum leaks and flushed the radiator.

Now when I drive, it drives fine except when i release the gas. When I do, the car jerks back like im down shifting, and when i barely press the gas again it jumps forward. Pretty much, I can't stay at a constant speed, it's always slowly accelerating so i have to release the gas and press it again on the highway constantly. I thought it was the throttle body at that point, so i covered the tb with my palm and it stalls of course. I replaced my map sensor, and have a new tps sensor but i didnt put it in yet.

When i take off my tps sensor, the car stutters then idles a little lower, more regularly, but i try to drive and it wont pass 2000 rpms. I'm not familiar with calibrating my new tps sensor, but my CEL doesnt say TPS sensor so i didnt figure its the problem.

ALSO, when i put in another ecu, i have to constant hold the gas for it to stay on, otherwise it'll just die.

So what im asking is:

-Why does my CEL still throw vtec code when it works now?
-Why is my car idling like that?
-Why does my car accelerate like that?
-Why can't i use another ecu?

Thanks for any help guys!

I have experienced a similar problem with my Honda Accord and I've done the very same checks and changed the same parts. I discovered a problem with the connector for the oxygen sensor. The wires get old and brittle over time and they were breaking off at the base of the connector. Its is very hard to find that unless you are looking there. It solved my idle problem and the excessive fuel consumption.

Jovo

Recently I've encountered this problem and the only thing that worked for me was unplugging my Vtec Solenoid. It fixed the idle surge and the lurching when I let off the gas etc. I have no clue what the problem is and I was hoping someone on here may have figured it out given that this post was made in 2010😂. Any help would be appreciated.