recently, ive been battling a mysterious surging idle in my h22a accord. after doing countless searches here, and on other boards, i noticed lots of people had the same problems, but not many of them seemed to fix them.

after going through all the possibilities and suggestions from previous posts, my surging still persisted. im mostly posting this to help people who have been through what i have and are still frustrated by the annoying surge.

if youve tried cleaning or replacing the EACV (or IACV as its sometimes called), checked the screw in the fast idle valve, checked over and over again for vacuum leaks, and tried all the unconventional methods from begging the car to makeing late night virgin sacrifices to the honda idle gods and the surging still persists, do this:

bump up the voltage being sent from your TPS sensor.

when i was calibrating mine, everyone said, "oh, it should be at .5 closed, and 4.5 WOT." well i set it at .5 closed, but at WOT, it would only reach about 4.3 ish. so after trial and error, i ended up setting it to about .63 closed, and at WOT it ended up being 4.5, and the car idles perfectly now, no surging.

just thought i'd post this for those who have lost all hope, and to help people who will invariably have this problem later, as none of the other posts helped me out.

 

how do you bump up voltage on the tps? i also have a bad idle, and i've cleaned my IACV and messed with my fast idle valve, it's still messed up.

 

I'm also interested in this - now the ECU thinks that you have your gas pedal slightly pressed at idle, right?

 

i think he has the aem ems..

i think..

im having the surging problem with my ems too, ill try this

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by j-speclude &raquo;</TD></TR><TR><TD CLASS="quote">how do you bump up voltage on the tps?</TD></TR></TABLE>

You can solder some resistors inline, or you can remove the twistoff screws on the TPS and adjust its position. You can use a hacksaw to notch the back of the screw, then use a flat head screwdriver to remove it. Replace it with a regular screw, rotate the sensor slightly with the ignition on and a volt meter on the middle wire to get the voltage you want, then tighten/locktight the screws. Same procedure applies to replacing the TPS. They get broken a lot on shipped engines because the plastic sensor sticks out. Oh, and you can't buy just the sensor from the dealer, so you normally have to pull one off a TB at a junkyard. Thankfully, almost all hondas use the same sensor so they are not too hard to find. hth....

 

exactly, loosen the screws, and turn it to adjust it while you read the voltage with a volt meter. i wouldnt reccomend doing this without a volt meter though, as it is pretty sensitive.

if it is set too low, at idle, the fuel mixture wont be right, and the engine will want to die, so the eacv clicks on to compensate, which in turn raises the idle too high, so it clicks off, then the engine wants to bog again, so the eacv clicks on, etc etc etc.

or at least thats what i imagine is happening.

my idle was only doing it when my headlights were on, and i discovered that if you turn on the headlights, the tps puts out .1 less volts...

crazy honda technicians

 

That is weird. The voltage should not change with the headlights on. It could be that the engine wire harness is not right. There are a few different grounds in the wire harness. The TPS should use the sensor ground. Or maybe you were using chassy ground with the volt meter. You can also hook up the volt meter to the pins in the ECU and measure exactly what the ECU is getting. I guess you could datalog the sensor too. If the wiring is ok, then it sounds like the 5v voltage regulator inside the ecu could be going bad. Anyway, I guess I don't really have a point. Sounds like you got it working; thanks for sharing the info...