I've got a problem with my 92 CX with b18c1 swap. The car seems to have a bad idle, vacuum leak sounding.. Pumps to 1500 rpm then drops to 800rpm, continues. it's SOO annoying! I hate the sound... anyways.. the noise goes away when i disconnect the IACV sensor.. But when I do that the CEL goes on. No CEL when it is plugged in, just bad idle. Any ideas? (it all started when I replaced my bad fuel filter... also, I removed the IACV and cleaned it thoroughly with CARB CLEANER after the problems started...)
HELP!!!
-Anthony

 

Any help please?

 

Come on guys!

 

You might just need a new IACV, I would check the continuity to the wires as well. IF the IAC has 3 wires in its harness, connect the negative probe of an ohm-meter to the middle terminal. Then connect the positive probe to each of the other teminals in turn. There should be 16 to 28 ohms in each case. If the IAC has 2 wires in the harness connect the positive wire (black/yellow) to the battery and the negative side(black/blue) to a ground. There should be a click every time voltage is applied. If not replace the IAC. Hope this helps

 

by ohms do you mean volts? ohms are resistance

 

i had a similar problem in the past, almost like a vacuum leak.
it turned out to be the TPS. i replaced the TPS and everything worked perfectly.

it may be the IACV, the TPS or maybe something else.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 93preludeh22 &raquo;</TD></TR><TR><TD CLASS="quote">by ohms do you mean volts? ohms are resistance</TD></TR></TABLE>

use a multimeter, then youll be able to find out what is up

 

how do I check the TPS ?

 

some sensors need the resistance metered, whereas some need the voltage metered.

the TPS needs the voltage to be metered, while plugged in with power/ground.
should be between .5 and 4.5 volts depending on the butterfly plate angle.
just tap into the correct wire on the TPS with a multimeter probe and ground the other one. then move the butterfly rotor to check the voltage. i don't recall off hand which color wire is the + to check though.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by sweet &raquo;</TD></TR><TR><TD CLASS="quote">some sensors need the resistance metered, whereas some need the voltage metered.

the TPS needs the voltage to be metered, while plugged in with power/ground.
should be between .5 and 4.5 volts depending on the butterfly plate angle.
just tap into the correct wire on the TPS with a multimeter probe and ground the other one. then move the butterfly rotor to check the voltage. i don't recall off hand which color wire is the + to check though.

</TD></TR></TABLE>

red/black= positive

 

Where is the TPS? (sorry!)

A picture would be much appreciated, please.

Thank you

 

Buddy,

When you unplugged the IACV, the jumping idle goes away. Try turning your idle set screw on the throttle body.

I had this happen to me with my H22 swap into my accord. All i had to do was turn the set screw 180 degrees and no more jumping idle for me.

 

why would the idle set screw fix this?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 93preludeh22 &raquo;</TD></TR><TR><TD CLASS="quote">Where is the TPS? (sorry!)

A picture would be much appreciated, please.

Thank you </TD></TR></TABLE>

on the back of the throttle body it should have green/black, red/black, and yellow/blue wires coming out of it

 

WHERE IS THE IDLE SET SCREW!!!!

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 93preludeh22 &raquo;</TD></TR><TR><TD CLASS="quote">WHERE IS THE IDLE SET SCREW!!!! </TD></TR></TABLE>


right next to the map sensor on the TB

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by TeStUdO &raquo;</TD></TR><TR><TD CLASS="quote">right next to the map sensor on the TB</TD></TR></TABLE>

yes, and you will notice it's right under the throttle cable rotor.
by adjusting the set screw you can change the postion of the throttle plate/butterfly at idle. this may help your situation.

 

how do you adjust it. I don't know how... Do you do it while the car is on?? which screw is it!!

 

Is it a screw? Bolt? Size of bolt? etc.. HELP!!!

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 93preludeh22 &raquo;</TD></TR><TR><TD CLASS="quote">Is it a screw? Bolt? Size of bolt? etc.. HELP!!!</TD></TR></TABLE>

it's a screw that you use a flat-head screwdriver on. it's directly above the throttle body. the best way to adjust it is have a portable tach meter or in my case I had a timing gun that also measured the rpms. the cooling fan should switch on twice before you adjust the idle screw and the engine is at normal temperture.

 

yes the adjustment screw is on the top of the TB like sleeperciv mentioned above, and you use a flat head screwdriver to adjust it.

to clear up an possible confusion, the screw i was referring to originally was the throttle rotor set-screw which is underneath the throttle rotor where the throttle cable attaches. normally you shouldn't have to mess with that, but it can be adjusted to order to alter the Butterfly plate angle. whereas the screw on top is normally used to adjust the idle rpm since it's much easier to use. if neither screw adjustments make a difference then definantly meter the TPS if you haven't done so already to see what the voltage is.

 

it works!

 

i had a similar problem on my c1. it turned out to be the fast idle valve under the throttlebody. on the valve there is a steel cover held on by 2 8mm bolts, inside there is a plastic retainer that screws in... mine had backed out and car idled between 1000-2300 up, down, up, down. tightened it up and it idles perfect now.

 

i swaped a gsr into my 97 hatch and had the iacv code keep coming up but i tested the iacv and it checked out. i then replaced the gasket in between the intake manifold and the throtle body and it stoped the surging idle and the iacv code.