Pezgoon

Also forgot to add it has a flow master exhaust, dc sports headers and k/n cold air intake Also the engine was replaced with a JDM not USDM

Hello there, I have a 95 del sol automatic with a d16 (recent replacement one same engine type though) that I just purchased that is doing some interesting things while idling. I have cleaned the FITV and adjusted it so now cold it starts at 1800, what is the standard rpm for cold idle start? I just replaced my IACV and this helped (the idle no longer surges and seems to handle loads much better than the last one) after cleaning the last one hadn't fixed the problem. What happens is is that as its cold idling the fitv slowly lowers the idle as it seems it should until it reaches about 800 then it will start to lower it all the way down to the point of stalling the car (with no load) I have tried bleeding the cooling system and it doesn't really surge, it will just lower it down to 500~ and just keep it there with the engine chugging, I have to either start driving or give it gas to keep it higher than 400-500 and this happens before the temp need reaches the first cold mark, once it reaches the first cold mark the iacv seems to kick on and it idles alright, still lower than warm but doesn't chug it at 500 rpm, any ideas? I've checked for vacuum leaks and just replaced the purge solenoid today so I can't try a cold start again till tomorrow morning could this be causing it or could it be the FITV valve spring is weak or something like that?
Any thoughts?
Thanks!

Pezgoon

Love the car other than that though! best car I've owned so far!

jlk16188

you need to follow the idle set procedure and adjust the idle adjustment screw on the throttle body.

warm the car up
turn the car off
unplug the wire harness connector to the IACV
start the car
set the idle with a straight screw driver by adjusting the brass idle adjustment screw on the throttle body to about 800 RPM
turn off the car
plug the IACV back in


done

Pezgoon

I've done that and it works great once its warmed up but getting there it struggles and that idle setting doesn't seem to "kick in" until the temperature is halfway to warm, almost like the IACV doesn't take over and start controlling the idle until the needle has reached the first marks on the temperature gauge, my problems are before the needle reaches the temp gauge but seemingly after the FITV disengages

Is it that the FITV is disengaging too quickly?

Pezgoon

I also rem app the ECU every time I change the idle so its not that either( unplug backup fuse, wait, put back in, let car idle with no load for 7 minutes) it works fine once its warm! its just getting there is the problem… what is the normal cold start rpm? it was at 1200 when I got the car and that seemed way to low and disengaged the FITV way to quick so when I cleaned it I turned it up a bit so it starts at 1800 is the average? I can't afford an FSM and the haynes is useless about specs like that

Pezgoon

Do any other sensors control the idle? like if the map was bad or dirty would it affect the cold idle? the cold idle seemed like it was controlled by the FITV alone considering its a pretty manual and basic system (using the same idea as a thermostat using wax and such)

Nave43

Did you screw the FITV all the way down when you cleaned it? Did you check the FITV and IACV for vacuum leaks?

Pezgoon

no I didn't, I set it 5 turns in (when I undid it it was 6 turns in) How do I check them for vacuum leaks? or should I pull them off again and vaseline or lubricate the seals to make sure there is a seal. it doesn't act like a vacuum leak (up until i did the solenoid it would act like a vacuum leak while idling while warm and even throw a vacuum leak code) if they leaks would it throw a vacuum leak code? as I've been getting such if i drive it while still cold
(below first temp marks)
now that I've done the solenoid I have to wait until tomorrow morning to see if code pops up again, as I asked is it possible to throw vacuum code if either of them do not seal?

Pezgoon

still, what is the normal cold idle rpm? this tells me if i even set the FITV correctly

Nave43

It maybe possible that once it warms up the seals also warm up and seat better thusly eliminating the vacuum leak until it cools down again. I am personally not experience enough to tell you if it would throw a code or not, sorry. To check you can just spray carb cleaner around the areas you suspect may have a leak. If there are no leaks it will have no effect. If there is a leak the motor will respond accordingly.

Lastly im not sure if Vaseline or other lube will do the trick, It may pollute the internals and make your problem worse. Did you torque the bolts to spec when you put them back on ? Did you remove the O rings before you cleaned the FITV? Cleaner can very quickly degrade the rubber.

PS. i would say your cold idle is in the right ball park, my sol idles around 1800k cold aswell.

Pezgoon

No I did not remove them, I tried to spray only inside the FITV and dry the seals as quickly as possible to avoid them drying. Would throttle body cleaner work instead of carb cleaner?

Good so its set right, I have a feeling the seals are dried out from when I looked at them (before cleaning) just as they are 20 years old and just seemed " tired"
The person I got my IACV from put new seals on it and for 35$ I may just replace the FITV. The FITV simply is acting "tired" like the springs don't hold it open for long enough idle up

If that weren't to clear up the issue is there anything it could be otherwise? would a vacuum leak mimic the symptoms? I really would hate to replace all lines as I'm sure there all tired, some have small cracks (early dry rot) in areas of high heat like the elbow on the intake manifold

Nave43

Instead of replacing the FITV, you could just get new O-rings. It maybe more price efficient to just replace it, but no point replacing it if its fine. There is also a good DIY here on H-T on how to properly and fully clean the FITV.... here is the link but sadly the pictures are down so its useless until its repaired...
https://honda-tech.com/acura-integra...valve-1564019/

Im not sure if throttle body cleaner would work...
\/ how to DIY for vacuum leaks \/

I dont recommend throwing parts at the car, its 20 years old and there plenty of "tired" parts. If you tried to replace them all you would have a money pit on your hands. Trouble shoot and if something NEEDS replaced then do it. Although preventative maintenance is never a bad thing. Its all about weighing the options.

TomCat39

1800 is about right when the car first starts and it casually drops to 750ish as it warms to operating temperature.

My 1995 D15B7 has always bounced to just under 2K on cold start (about 1800 I'd say). I wait until it starts dropping to about 1500 before I ease off to work. I don't pound it ever until it's fully warm or darn near.

I do believe the at operating temperature idle varies between Canada and USA and I think motors too. I'd have to peek into my FSM for exact numbers.

Pezgoon

Its supposed to idle at 700 for an automatic, I would just drive off like you said but once it starts slightly warming up it has no idle and I ave to rev the gas to keep it alive if I stop, its like the ecu doesn't know that there's no airflow/fuel or something but once the temp reaches the first couple lines past the first cold mark its fine, just in between absolute cold and barely warmed up it doesn't want to stay running

No cell's either after fixing the solenoid (was getting vacuum leak). The iacv has brand new seals also so there's no leak there and if the fitv had a leak itd affect the warm idle too but that has no issues once its warm

Nave43

Are you sure the IACV you got was good? Try tapping it with a screw driver. Does it stall with the IACV unplugged?

Are yous sure you correctly set the base idle? You must do it once the car is hot. (Unplug IACV and adjust idle)

Clean you throttle body just to mark that off the list...

Last resort
Main relay fuse ?
Bad timeing?
O2 Sensor?

Pezgoon

The IAcv I got was supposed to be tested and passed and it fixed my warm idle issues, when I unplug the IACV the idle goes to 1100 which I found unusual.. I have set the idle correctly as far as I can tell, I have to have the car off while unplugging the IAC though as it will go to 1100 if on and even with the idle screw bottomed out it won't go under 900+. If I unplug it while off then I can easily adjust the idle, is that normal?

Pezgoon

I also have cleaned the throttle body but I may do it with a atip cleaning the IACv and fitv holes just to make sure, would the main fuse still allow the car to run if blown? How would it run when cold or warm if the timing was off? Could it be valve lash? The engine only has 40k and I've now been reading valve lash can cause idle problems but what I don't get is why it happens in between warm and cold.. that's what stumps me

Pezgoon

I keep thinking it might be a vacuum leak but don't vacuum leaks raise the idle instead of lowering it?
Is it possinle the wax/liquid in the fitv can fail and cause it to close too quickly before the iacv can effectively control the idle?

I'm feeling like it could be a vacuum leak and as the car begins to warm whatever it is seals up, I've just thought from my reading that that would cause high/erratic idle which I have neither, it very determinately sits at the low idle.. it doesn't hunt just sits there chugging away slowing down at a consistant rate until it stalls. If I hold the gas pedal enough to keep I going and get even a couple lines on the temp gauge it idles fine.
I'll try and do a video tonight to demonstrate but seeing as its dark it may have to wait until tomorrow morning

Pezgoon

Also wouldnt the o2 sensor throw a code?

Nave43

You are supposed to unplug the IACV while the car if off. Ive never been ballsy enough to see what happens if you unplug it with the motor on. With the IACV unplugged to my knowledge the idle should be at whatever you set it to. Ideally around 800rpm.

Re-cleaning the throttle body is definitely not a bad idea. To my knowledge the car would run with the fuse blown, but that is more likely if it stalled all the time. Not just when warming up. Maladjusted timing is very hard to describe, you maybe best to research that one yourself.

I dont know enough about valve lash to tell you one way or another. I at this point i am also stumped. Hopefully someone else will come along and know more than myself... Although i am researching it for you, because i also am curious to figure out the cause.

Lastly the o2 would only throw a code if shorting or making the motor misfire, It may just be getting tired. OBD1 cars arent very precise with there CEL's

Pezgoon

Alright, any idea of how to check the o2 sensor?
The manuals specify to check the iacv by unplugging it while running
I'm going to look into the timing and valve adjustment things when I get home its tough at work on a phone Haha
I could imagine that the o2 sensor is getting tired but it looks almost brand new, it has a newer exhaust system on it although the body does have 169k

Pezgoon

This is when the FITV seems to fully disengage





This is where the IACV BARELY begins controlling idle and if theres no load the car will BARELY begin staying running, it'll stall if I put it in gear

Pezgoon

please take a look at the pictures to more understand what I'm talking about the temperatures that I am having the issues at, it doesn't seem like it may be relevant but I will attempt to again reset the it again on thursday to see if that has an effect, it sits about 600 after getting it warmer so maybe its just set too low causing it to affect the in between, it doesn't make sense for that but who knows.

Nave43

Just pull it out the o2 and see if it has carbon deposits. It maybe new but if your car has other problems they can be ruined quickly. Also may have been replaced with a shoddy o2. Avoid any o2 sensor that looks like a beer can. Get the kinds that have the holes through the tip. I believe "AC Delco" makes the OEM sensors.

Yes you check to see if the IACV is working by unplugging it while its running. To adjust the idle you unplug it with the car off.

Did you reset the computer after doing your adjustments?

Thank you for the pictures it gave me a better idea of what your talking about.

Have you tried putting a load on the system when its at that point? If it stalls when you put it in gear it makes it sound like strain on the system is making it stall, or at least contributing to the problem if it cant make up for the extra power used. Turn on your headlights, roll all the windows at once, use the power steering. Does this make the idle fluctuate or cause the car to die aswell?

I am trying to be helpful but i am as lost as you at this point.

Pezgoon

yes putting other loads on it do cause the idle to fluctuate just not enough to stall it, its more so if i put it in gear with any other load it stalls it right away i will test more in depth of the load affects tomorrow morning, I'll have to check the o2 sensors this thursday when I have time, should I pull both? Thanks for showing me the two types and what to avoid
Yes I did reset the ecu and also remapped the fuel each time (allowing it to idle for 7 minutes without any load after resetting the ecu)

I have just gotten my hands on an fsm tonight and after going through the charts heres what it tells me

Stalling while warming up
#3 coolant temp sensor (the IACV is supposed to actuate while cold also increasing the idle and stabilizing it more working with the FITV)
#2 Other idle systems (defined as #2 Idle adjusting screw {which my idle still may be set too low I have to recheck it} #1 IACV)
#1 IACV

The rough idle problems (which idk if this would fall under rough idle but maybe)
#3 MAP sensor/EGR control system
#2 Injector
#1 IACV

Under Fuel supply
Stalling while warming
#1 Fuel pressure regulator

I feel as though its not the fuel supply as it has no other issues although who knows haha


I have much trouble shooting to do not enough time to do it

Question
For the idle adjustment procedure it states to
Check The idling in no load condition
For automatic its supposed to be 420+/-
But I cannot stably adjust it to this figure as the car begins to stall out at this number so I've never actually tried setting it so low, I've always adjusted it to 8-900

Could that be causing the wrong idle?

after setting it to 420 your supposed to ten reset the ECU and re-idle/recheck and it is supposed to then idle at 700+/- rpm

When I set it to 8-900 it idles around 650 on its own, should that be happening? Is the IACV fighting me or am I fighting it and confusing it?

I don't have an external tach nor know where or can afford to get one so I'm using the incar tach, I know its not very accurate doing it this way but I guess I'll try and reset the idle to exactly what the manual specifies

What I don't know is whether this could make a difference, could me setting the idle screw be letting in too much air and at the colder temperatures the other systems cannot compensate for it? I feel as though by adjusting it lower it would only exacerbate the issue?

I probably won't be able to do it until thursday so if anyone has any info/ideas before that it'd be amazing, thanks for all your time Nave43! I'll keep you all updated