Recently i pulled off my intake to clean out the inside of my throttle body because my throttle was sticking a little . After i cleaned it I pulled the ecu fuse to reset it..Then right after i reset the ecu i got an erratic idle..I know theres been a lot of threads about this lately and Ive done plenty of searching...Today I bleed the coolant, checked the iacv ,and vacuum lines. Then i checked my tps and between the erratic idle revs, the tps was reading .415v and .420v, but the tps at idle is supposed to be .45 correct? So my tps is off .30 volts?

could this be my problem?


Modified by 92civeg at 11:09 PM 1/22/2004

 

i thought it was .40 but i guess i could be wrong.
thats what i meant to say. my bad.


Modified by BluntMan at 7:22 PM 1/21/2004

 

its .45 at idle and 4.5 at wot

 

at idle its .5v and wot 4.5v....

also check the plunger underneath the throttlebody wheret the coolant enter and exit..... there is a plunger in there that u screw in and out it might have backed its way out and need ot be screwed it...

 

what do u mean plunger?

 

so would this cause a problem.....my tps reads between .415v and .420v at idle.

 

no. should not cause problem at .415v .420v.

 

not actually plunger. Is actually called the fast idle thermo valve. they have a tendency to get old and the wax inside dries out and causes a vacuum leak.

Also, they are not meant to be adjusted. only replaced...

Have you tried setting the base idle first?

 

have any pics of a fast idle thermo valve?...where is it located?

 

ttt

 

i have the same problem as you and i don't know what the hell is going on.

my gas pedal sticks as well whenever i drive a bit aggressively or in boost. i thought it was the pedal itself so i sprayed some carb cleaner and wd40. it helped a bit the problem keeps coming back.

i then pop the hood and tried openning the throttle using the throttle spring by the throttle body and i found out the binding was happening in the throttle body and not the gas pedal. i took the intake pipe out then sprayed carb cleaner and use a clean cloth to wipe all the gunk i could reach.

after wiping it clean, i went for a test drive and i was surprised that my idling is very high already at 1500rpm and whenever i step on the clutch to make a stop, the rpm would bounce up and down for about 3-4 times before settling back to 1500rpm or rpm would jump to higher rpm range and stays there for few seconds before coming back to 1500rpm. i have no idea why my idling was suddenly at 1500rpm

i took out the iacv and throttle body and cleaned it thoroughly but to no avail. i tightened the idling screw but this didn't shut the engine coz only 200 rpm drop.

it seems to me that there's a leak somewhere. there's another source of air going into the manifold hence when i tighten the idling screw the engine won't stall. i also disconnected the iacv while idling but engine didn't stall and only 100 rpm drop. i installed a good iacv from my parent's crv and still didn't help. so that means iacv is working and the engine is getting another source for air but where can it be?

it's so very frustrating since i only sprayed carb cleaner and wipe. didn't even took the TB out yet.

i hope someone can enlighten us on our problem coz it's really annoying already.

 

Sounds like maybe a vacuum leak. Have you tried disconnecting the IAC and then turning in the idle set screw on TB to see if engine dies yet?

I'd start by trying this. Sounds like base idle could still be too high.

 

i did unplugged the iacv and turned the idle screw all the way but engine didn't stall. also tried a working iacv but same thing too.

 

Well then, remove intake tube and there should be 2 holes on inside of TB. try pluggin both of these holes with your fingers with engine running and see if engine dies then. If it does, then you possibly need fast idle thermo valve. If engine does not die, you either have a vacuum leak or throttle plate sticking open.

I forget, did you have stock TB on vehicle or aftermarket?

Let me know...

 

92civeg,

i don't mean to hijack your thread but since we have the same problem, i decided to share it here also rather than create a new thread. hope you don't mind.

hondatim,

what two holes are you referring to? i remember that there are 2 small holes side by side, immediately before the throttle plate, about the 1-1.5mm diameter. is that the two holes you're referring to?

i can't take off my intake right now coz i'm still at work but i'll try your suggestion and i hope this get fixed and i'll post the result here for people with similar problem especially 92civeg.

i'm using stock TB and the car is a 99 SiR.

thanks man.


Modified by _Endless_ at 2:35 PM 1/24/2004

 

_Endless_.....don't even worry about jacking the thread...we both need our problems fixed.... tomorrow im gonna check out my fast idle thermo valve, Ive tried almost everything!...also since it just started to happen after i reset my ecu could it just be the ecu "learning itself "over again???

 

92civeg,

Yes, those are the 2 holes I was referring to.

Endless,

Yes, it could be possible for ECU to have to relearn, however, shouldn't take longer than 5-10 minutes for this procedure to happen. If happening longer, possible problem with idle issues as we were talking about before. Try what I suggested and let me know your findings. I'll try to help as much as I can, short of obviously being there to diagnose and repair the vehicle myself.

Again, let me know

 

ok here's what happened:


the throttle body we have here on our SiR is kinda similar to the pic above. it has a hole for the IACV at point A, two small hole at point C. the two small holes are in a row and about 1mm in diameter, these two holes are connected to point B. so if you blow through point B air will come out of the two small holes at point C. there's no "FAST IDLE THERMO VALVE" in there or underneath the TB...maybe there's none and probably the same reason why we don't have o2 sensors on our SiR.

anyway, i don't know what point C and B are for, but point B is connected to the EVAP canister by a hose thicker than the typical vacuum hose.

i took off the turbo intake pipe and started the car. i stick a finger at the hole mark as A which is for the IACV and the rpm drop only slightly whereas before the engine would stall....seems like there's another source of air to keep it idling.

i stick a finger on the two small hole indicated as C and the rpm didn't change at all. again, i don't know what these two stupid holes are for and they're connected to the EVAP canister.

one more thing, i sprayed some carb cleaner at the joint where the TB and IM connect and there are two parts that are leaking since the rpm dropped after spraying carb cleaner which mean vacuum leak...

BUT that's not the main issue here, the main issue is, why did my idling change so suddenly upon spraying carb cleaner to the TB and wiping it with a clean cloth coz of sticking gas pedal. that's what making me go nuts. i didn't touch anything anymore so i'm thinking that even if i put a new TB gasket in(tomorrow) the silly idling would still be there.

the leaking at the joint was cause by the TB gasket which i didn't replace with a new one when i took the TB off for cleaning and hoping it was just a case of dirty TB.

 

Ok, my mistake...
Those 2 holes on top are ported vacuum sources. Not the hole/s I was trying to refer to. Sorry

the hole I was referring to was labeled A in your picture.

You say you plugged finger over hole A and that engine did not stall?

This definitely means vacuum leak...

I also understand now that when you sprayed carb clean on mating surface of TB and IM idle dropped, obviously meaning vacuum leak.

Now why did this happen only after cleaning throttle plate and TB? I didn't know that you mentioned that you removed the TB in order to clean.

When you removed TB, it probably tore gasket (happens all the time) upon removal, this would definitely cause the vacuum leak.

I'd replace the gasket and the set base idle after repair (since you will now need to because of messing with it before) and everything should be fine after repairs.

Sorry again for the misunderstanding... I should have asked you if you had removed TB before, instead of sending you on a rat race of diagnosis.

 

so i should put my finger over the A-hole (haha) while the car is running and if it dies i have a vaccum leak?


i took a closer look at my fast idle thermo valve today....is it easier to take off from underneath the car or on top, it looks like it its gonna be a pain either way.

 

No. If you plug IAC port (aka. A-hole ) and engine idle doesn't change or engine doesn't stall, you could have a vacuum leak somewhere.

Sorry if I confused you

 

no problem dude. it's not your fault as this is really confusing. i wasn't that clear on my explanation also.

anyway, now we know that i have a vacuum leak between the mating surface of the TB and IM because i took off TB for cleaning and that's understandable. what i don't get right now is, why did me and 92civeg experienced high/dancing idle when we just take the intake off our intake pipe and sprayed carb cleaner in it in the first place(coz of the same sticking throttle situation)? this spraying of carb cleaner and wiping started it all(even before removing TB for cleaning) but the taking off the TB just made it worse for me coz now i have a vacuum leak on the mating surfaces. this is really confusing i bet 92civeg didn't mess with anything but just sprayed carb cleaner. i like to know coz i'm afraid that when i replace the gasket with a new one the problem might still be there. our cars might be possessed. haha.

i'll replace the TB gasket this afternoon(it's hot outside right now) and i'll keep u guys updated.

by the way, i forgot to mention that when use my hand to shut the TB further while idling by pushing on the bronze color thing that houses the throttle spring, the idle drops a bit. could it be the throttle plate is not closing? could there be some sort of sealant that when me and 92civeg sprayed some carb cleaner, the sealant washes away? hmmm...

92civeg, you might want to try shutting the TB further with your hands and see if your idling will drop a bit.

 

Now throttle plate should actually not close all the way. This tiny bit also allows engine to idle at proper rpm. If was closed all way idle may be too low, as well as, cause throttle plate to stick when closed in the throttle body.

As for when spraying TB with carb clean. I have experienced this a couple of times. For some reason, IAC can go crazy trying to re-hunt for proper idle. Don't know if it clears carbon off of idle circuit (the one that the idle set screw controls) and fools IACV or what. I have had this happen quite a few times on 98-newer Accords with 4cyl. when trying to clean throttle body for a sticking condition.

Generally been able to reset ECU and then re-set base idle (as described above) and idle has always been corrected.

 

ok i replaced the TB gasket with a new one. but that didn't completely solve the problem.

while i was cleaning the TB(again but using toothbrush) i tried pouring some water in the throttle plate to see if it had any leak. there's a very minute leak below part C but a big leak and water came dripping fast on the pivot of the throttle plate where the throttle cable is attached. the Tps side pivot had minute leak as well but not as great as the throttle cable side.

when i first started the car, same thing again, rpm would rise to 2k rpm like someone is stepping on the gas pedal slowly bringing it to 2k rpm then drop gradually again to about 950rpm. i blocked the A hole(iacv) and the engine didn't stall at all and the rpm didn't drop much.

while engine is idling and i standing in front of the TB, i could hear hissing sound of air. i plugged a finger on the pivot of the throttle plate(throttle cable side) and it was coming there. the hissing pitch would change everytime i press my finger in and out. i tried closing the throttle plate further and idle will change but i don't experience this with my parent's CRV.

i think it the TB is broken already. maybe when i sprayed carb cleaner to eliminate the sticking gas pedal, it wipe away whatever grease/sealant is in there and created the leak. same thing happen when i sprayed my BOV to see if it's open at idle or not, the next day it wouldn't blow off anymore and i had to open it up and re-lube it. i guess the only way now is to buy a new throttle body coz i don't think this is repairable right? damn, i can't believe this is happening.

by the way, while i'm at it, i bypassed the coolant line going to the iacv and TB since i live in tropical climate plate where it's mosty warm/hot all year round. don't know if this mean anything.

92civeg, were u able to fix your idling problem?

 

Well, it sounds like you TB shaft bushings are worn out.

Sounds like it's going to need a new throttle body.

Sorry I couldn't help you any more with your issue