CRX410

Hi everyone! my name is Aaron . I got a 1989 Honda CRX DX with a B18A1 swap. i just had alot of things fixed with it, but now after a few months the car decides when it wants to start and now with a high rev of 2k-3k RPMs out of no where. if anyone can give me some info on it or where to find the info i would thank you alot. i have had this car for 3 years and dont wanna give it up. this is the 8 motor i put in it.

sinepome

check for a vacuum leak.
clean your iacv.
search.
welcome.

FOMULA91

iTrader: (3)

so your car is surging 2000-3000 RPM?

Got this directly from Ben's EF resource...

1) Check your vacuum routing. On the underside of your hood there should be a vacuum diagram. If there isn't a diagram under there, there is one in a Helms, Chiltons, or Haynes manual for your car (you should have one of these anyway). Remember, ANY extra air will confuse the ECU. Check for cracked or bad vacuum hoses. If in doubt just replace the hose, they are cheap.

The PCV valve could also be the culprit. Take it out and examine it. If it is cracked it could be causing a vacuum leak. Replace the peice if you arent completely sure it is ok (the helms/chiltons/haynes manuals tell you how to check it).

2) Check to see that your throttle plate is closed all the way. Take your intake off at the TB and check to see that nothing is blocking the plate. If nothing is in the way and it isn't closed all the way, loosen your throttle cable.

3) Check to see if the nuts holding the TB and the IM on are tight, this was the source of my idle problem. If they are loose, tighten them.

3.5) Check the Idle screw. Its on the top of the TB right next to the red vacuum line in the first picture. Its a flat-tip screw and most TB's have it epoxied over. If your screw is not epoxied over try adjusting it.

4) Bleed your coolant. Some air bubbles may throw the FITV off and keep the valve open.

5) Take the 3 10mm bolts out of the FITV (you don't have to take off the coolant lines). Then take off the 2 8mm bolts off the plate on the back of the FITV. Once the plate is off you will see a white plastic thing, screw that all the way in. This causes a TON of people's hunting idle problems (it's a source of a vacuum leak). Put the FITV back on and start the car up. If it still idles bad go on. Here is a writeup on the FITV.

6) Clean the IACV screen(s). See Oz's write up on G2IC.

7) Make sure your car is completely warmed up. With it running, take the intake off the TB. There are 2 holes right in front of the throttle plate, these are the holes that feed the IACV (top hole) and the FITV (bottom hole). With your finger, cover up the bottom hole (it should NOT be sucking if your car is warmed up). If the idle goes down the FITV is to blame, either get a new one or take it apart and screw the valve completely closed (I have only read of people doing this, so I don't know exactly how. Also, you will have to keep the engine speed up yourself when the car is cold).

Next cover both holes up with your fingers. The car should sputter and die (or almost die). If it does then the source of your crappy idle is the IACV. Replace it. If you want you can test the IACV. Shut the car off and put + battery voltage to the blk/yel terminal (on the valve) and momentarily touch ground to the blu/yel side. When doing this the valve should click, if it doesn't, replace it.

If, when covering both holes the car still has a high idle, you have a vacuum leak somewhere. Again check the IM and TB nuts. You can spray carb cleaner around those areas and if any gets sucked in (the engine will rev) you have found your leak. Another source of vacuum leaks are where the FITV and IACV connect to the IM. Either replace the gaskets or use silicone gasket sealant.

8) If nothing has worked you should test your TPS. Probe the middle wire on the TPS plug (with the key on but not running, and the plug still connected to the sensor) with the + probe on the volt meter, and the neg probe to ground. You should have .5v with a fully closed throttle plate and 4.8v with it wide open. If the TPS is off, replace it. My TPS was .425v to 4.55v and it idles fine now so I don't know how big the margin of error is. Also, it is pretty rare for these to go bad.

punkdown

You weren't completely clear on if this is related to your idle issues... if it's a separate problem it's most likely your main relay taking a crap.

jhmed9

wow! 8 engines in 3 years really? any particular reason why?

CRX410

i have switched out the main relay before.i had wire problems when i had the JDM B16A but nothing has went wrong with this motor. i went out and bought plugs. They looked pretty nasty with white. i think thats means it must of ran lean.and changed my Cap . is there a difference in the LS and RS motor. cuz i LS cap does not fit my car. i looked for any vac leaks with carb cleaner but no rough idle from that. the valve on the TB is all the way in. if i losen it up, it revs higher. i went out and bought cleaner spray for connectors and see if that will help out. and the other stuff i dont know. i dont know all the codes for names for sensors and other parts you were talking about " IM" and FITV.

Daniel jdm

bump.

CRX410

i kept putting in SHOC D15 back in from junk yards. i was low on cash and needed a way to get to work. but the B16 was only 300.00 for everything but blew the head off it

CRX410

heres some pictures of the motor. i took the TB off put coolant lines run through it. i notice just today. the guy that helped me put the motor in bypassed the bottom part where the coolant flows through with something but i dont think that mean nothing because this should of happen when i first ran the car. i blead the coolant i think. theres a nut that uses a 12mm to loosen it up it looks like a bleeder valve so i blead it untill coolant came out smooth. ( car was running though). used throttle body cleaner to spray lines but no effect of idle difference. should i goto the junk yard and find another TB? TPS and Idle air control sensor was sprayed with connector cleaner but no work. im clueless.

CRX410

90honduh

id check for vaccume leaks. or one time my car would idle a 3k and threw a map code. but i just reset my ecu and its ok

jhmed9

aww dude that sucks. no more junk yard stuff, okay? lol. so what happens when you turn the key and it doesnt start? nothing, a click, etc? also when it does that can you push start it?

CRX410

when i start it, it cranks and all. But will not turn over. I just took the pcv Valve out and the hose. the hose has a pinch like a 1 long in the hose. you think it might be that? i have not had a chance to jump start it but it turns over now with no pcv valve now. but now revs at 4000 RPM. ??? You think it might be that?Im going to the junk yard and snaggin some Main relays and sensors just in case. lol no the whole motor though.

jhmed9

it doesn't sound like anything electrical. just a funky vacuum leak. fix the pcv hose! then go from there.. shake the pcv valve to make sure its good before you put it back too..

CRX410

so if the PCV valve does not have a rattle to it,its bad? The one i pulled out of the car had a little rattle to it but it looks spring tension though.

CRX410

So the PCV valve was an EPIC FAIL. Still high rev. I Dont know what to do now. any ideas? could a sensor gone bad?

jhmed9

yea the pcv valve has parts inside that move, making the rattle when you shake it. it'll get full of oil and become solid, sealing itself shut (no longer functioning).

so its turns but doesnt catch.. and you have tried a main relay that you are certain is good? the fump coming on? take your gas cap off n have a buddy stand with his ear close to the filler hole, turn the key to on position (not start) and listen for the hum.

i had a pos lude that the pump was going bad in, and i used to get a rubber mallet and beat the gas tank and it would come on,lol.

has it always had the same idle problem? or did it start after the no-start problem?

gringo7718

Try this. FITV - Fast Idle Throttle Valve.

https://honda-tech.com/forums/showth...highlight=fitv
https://honda-tech.com/forums/acura-integra-6/%2A%2A%2A-how-%2A%2A%2A-clean-your-fitv-aka-fast-idle-thermo-valve-1564019/
https://honda-tech.com/forums/showth...highlight=fitv