Idle Problems - ECU Change??
- Thread starter RNP
- Start date
Hi RNP, I had read you had no luck changing the IACV but hope it will sort my issue.
I read a few 'new' bits of information trawling through here, I don't have the posts to hand but two new possible things I will research are:
"IACV 'sensor' has a very small amount of adjustment" the post said after adjusting this it solved their idle issues. (I will try to find this post again and link to it, its about three or four pages into this forum's 'faults and fixes' section.
Lastly someone has mentioned a 'idle slider' on the ECU in this thread, I have not heard of this before. Again I will do some research.
I'll be buggered if I'm not going to sort this!
I read a few 'new' bits of information trawling through here, I don't have the posts to hand but two new possible things I will research are:
"IACV 'sensor' has a very small amount of adjustment" the post said after adjusting this it solved their idle issues. (I will try to find this post again and link to it, its about three or four pages into this forum's 'faults and fixes' section.
Lastly someone has mentioned a 'idle slider' on the ECU in this thread, I have not heard of this before. Again I will do some research.
I'll be buggered if I'm not going to sort this!
https://www.hondata.com/techidle.html
Interesting and informative explanation to the idle process.
I have just set my TPS 'idle' value to 0.45v perfectly, it was previously 0.47v. I then completed the 'idle teach' process with the ecu but its still behaving the same. Its ok to drive but when coming to a stop the idle hunts anywhere between two to five times from the 'correct' warm idle of 850rpm up to 2000rpm then settles and in my opinion 'controls' the idle at 850rpm. Im still hopeful the new IACV valve will bring this back into check.
Stu
Interesting and informative explanation to the idle process.
I have just set my TPS 'idle' value to 0.45v perfectly, it was previously 0.47v. I then completed the 'idle teach' process with the ecu but its still behaving the same. Its ok to drive but when coming to a stop the idle hunts anywhere between two to five times from the 'correct' warm idle of 850rpm up to 2000rpm then settles and in my opinion 'controls' the idle at 850rpm. Im still hopeful the new IACV valve will bring this back into check.
Stu
Thanks for sharing. For your info, there is an idle adjustment knob on the iacv which you can manually adjust for the amount of airflow required during idle. I request that you DO NOT adjust this especially when you get the new iacv. A new one has already been set by Honda and it should be plug and play. Reduce the number of variables you have by not adjusting it..
Quick update on this fault and where Im at as I hope it could help others. I have had the car running three days now, 'perfectly'. No idle issues or issues with the idle coming to rest which was my main issue.
Originally when I bought the car the idle wasn't quite perfect in my opinion which lead me to cleaning the throttle and IACV which wasn't filthy but the muck in there certainly hindered movement. Once all cleaned the idle was all over the place.
Skipping out all of my previous posts the solution came by doing the following:
Throttle adjustment screw (grub screw underneath the cable pulley on the throttle body) I backed this off completely then wound it in so it just made contact with the pulley when in closed (zero throttle) position. It was set so it could be described as still fully closed.
I then set the original TPS to 0.45v at closed position. Reading the Hondata info on the throttle I totally agree that 0.01v either way has an affect on the idle. Take the time to set this exactly. I did not even check WOT voltage at the TPS but knowing it like the back of my hand I would expect it to of been around 4.9v.
I reset the ecu (pulled fuse for 20seconds) then ran the car stationary up to around 3000rpm to working temp (fans kick in) then left to idle like this for 10mins, turned off the ignition then back on and went for a drive.
The idle is perfect and so is throttle response, happy days. I use Torque on my head unit via a OBD2 transmitter and at rest my throttle is 7.5% and WOT is 90% for reference.
So to sum up, the TPS and the idle system is very sensitive. Fingers crossed mine stays like this now and I hope someone else gets a result from using the above setting up......
Stu
Originally when I bought the car the idle wasn't quite perfect in my opinion which lead me to cleaning the throttle and IACV which wasn't filthy but the muck in there certainly hindered movement. Once all cleaned the idle was all over the place.
Skipping out all of my previous posts the solution came by doing the following:
Throttle adjustment screw (grub screw underneath the cable pulley on the throttle body) I backed this off completely then wound it in so it just made contact with the pulley when in closed (zero throttle) position. It was set so it could be described as still fully closed.
I then set the original TPS to 0.45v at closed position. Reading the Hondata info on the throttle I totally agree that 0.01v either way has an affect on the idle. Take the time to set this exactly. I did not even check WOT voltage at the TPS but knowing it like the back of my hand I would expect it to of been around 4.9v.
I reset the ecu (pulled fuse for 20seconds) then ran the car stationary up to around 3000rpm to working temp (fans kick in) then left to idle like this for 10mins, turned off the ignition then back on and went for a drive.
The idle is perfect and so is throttle response, happy days. I use Torque on my head unit via a OBD2 transmitter and at rest my throttle is 7.5% and WOT is 90% for reference.
So to sum up, the TPS and the idle system is very sensitive. Fingers crossed mine stays like this now and I hope someone else gets a result from using the above setting up......
Stu
Very glad for your situation Stu. So am I right to say you managed to solve it without installing the new iacv? And the solution came by way of setting the tps exactly at 0.45v at closed throttle and ensuring that the throttle cable was adjusted to have barely any tension when at closed throttle?
By virtue of this, is all I have to do when I get my new throttle body is to set the throttle cable properly and do the Ecu reset and idle learn process you did?
By virtue of this, is all I have to do when I get my new throttle body is to set the throttle cable properly and do the Ecu reset and idle learn process you did?
Cheers Matt, are you Tegiwa Matt?
RNP- Correct, old IACV and old TPS. The cable tension has nothing to do with it (in my case anyway). In fact I will look into taking a small amount of slack out of my cable as I think its possibly on the plus side of 12mm (from memory) deflection when set correctly.
If I was doing this again I would do the following:
1. Remove throttle cable along with the final bracket before the throttle pulley and air intake hose.
2. Adjust the closed position dead stop (small grubscrew with 7mm AF nut) so that the grub screw just about makes contact with the pulley. This gives what looks like the throttle a fully closed position when at rest.
3. Adjust the TPS with the throttle at fully closed position just set as above to 0.45v perfectly. I have soldered a test lead onto the relevant wire to make getting the reading as easy as possible.
4. Re-fit all parts. Reset ECU, warm up engine (around 3000rpm) until fans kick in than leave it to idle for 10mins. Switch off then back on and try it out.
The throttle cable is possibly the least most important part of all of it as a unit. Like I say the Hondata page linked above give insight on how it all works and just how finite it is.
I'll re-write this if its not easy to read/understand. I just hope it works for others too.
Stu
RNP- Correct, old IACV and old TPS. The cable tension has nothing to do with it (in my case anyway). In fact I will look into taking a small amount of slack out of my cable as I think its possibly on the plus side of 12mm (from memory) deflection when set correctly.
If I was doing this again I would do the following:
1. Remove throttle cable along with the final bracket before the throttle pulley and air intake hose.
2. Adjust the closed position dead stop (small grubscrew with 7mm AF nut) so that the grub screw just about makes contact with the pulley. This gives what looks like the throttle a fully closed position when at rest.
3. Adjust the TPS with the throttle at fully closed position just set as above to 0.45v perfectly. I have soldered a test lead onto the relevant wire to make getting the reading as easy as possible.
4. Re-fit all parts. Reset ECU, warm up engine (around 3000rpm) until fans kick in than leave it to idle for 10mins. Switch off then back on and try it out.
The throttle cable is possibly the least most important part of all of it as a unit. Like I say the Hondata page linked above give insight on how it all works and just how finite it is.
I'll re-write this if its not easy to read/understand. I just hope it works for others too.
Stu
Just an update, I spent a small fortune on brand new throttle body. The idle problem has been resolved. Just for info, this was on the old throttle body i changed out:
- Fully stripped and cleaned
- No undue tension on flap due to throttle cable
- brand new IACV
- map sensor changed out from a serviceable throttle body
- New throttle body gasket
- Checked for leaks
- Ktuned V2 TPS (installed less than 6 months ago)
I will update Mike from Ktuned on this before I comment any further. Thanks for the help and interest all.
- Fully stripped and cleaned
- No undue tension on flap due to throttle cable
- brand new IACV
- map sensor changed out from a serviceable throttle body
- New throttle body gasket
- Checked for leaks
- Ktuned V2 TPS (installed less than 6 months ago)
I will update Mike from Ktuned on this before I comment any further. Thanks for the help and interest all.