Throttle Body Question. - Honda Prelude Forum

batcave00 · 03-09-2010, 02:32 PM

i was cleaning my new preludes throttle body and i saw what appeared to jb weld. on the side of it just before the butterfly on the bottom left side. i know that is not supposed to be there?

do any of you guys know what that jb weld might be blocking? on other preludes i know theres a hole of some sort. not sure how this might affect me. by the way vtec is not hitting and the car is hard to start...any ideas?

all help is appreciated, thanks in advance.

dontbuyprelude · 03-09-2010, 03:01 PM

your car probably had a messed up idle.
the test procedure calls to put your finger over the little hole and if it gets better then one of the components need replacing. he probably put the jb weld there to "fix" the idle.

for the life of me i cant think of what that idle thingy is called

batcave00 · 03-09-2010, 03:45 PM

i did pull a code for electronic air control valve, which i think is the same thing as the iac Valve. if a get a new iac valve and install it, then i should remove that jb weld from the tb right?

another thing, whats making my car hard to start? i have to push the pedal while i crank to start it. is it cause my iacv doesn't work?

dontbuyprelude · 03-09-2010, 07:25 PM

i know you can try cleaning you IACV. just take it off the front of the intake mani and spray some carb cleaner in there and maybe get an old toothbrush and gently brush the gunk out.
i cleaned mine but i never had idle problems

dontbuyprelude · 03-09-2010, 08:04 PM

[IMG]

[/IMG]

batcave00 · 03-10-2010, 06:04 PM

both ports on the throttle body are closed and the car does does not stall. Vaccum leak?

dontbuyprelude · 03-11-2010, 12:19 AM

possibly a bad IACV or Fast Idle thermo valve. you can permanently disable the fast idle thermo valve like i did when i bypassed the coolant lines to the throttle body

batcave00 · 03-11-2010, 10:03 AM

it wont make my car run crappy if i close the thermo valve? if i disable it, do i need to get a new iac valve and open the lower port? thanks for all your help.

dontbuyprelude · 03-11-2010, 02:42 PM

this link is to clean your IACV. i wouldnt replace yours just yet. usually cleaning it will fix it. the only difference is in the link its for a gsr and the IACV is on the back of the intake mani. your IACV is on the front of the mani. it looks the same as the gsr one though. same procedure for you to clean it as for the gsr
***How-To Clean*** Your IACV a.k.a. Idle Air Control Valve - Honda-Tech

im currently running with a disabled thermo valve and my idle is perfect. no jumping, hunting, fluctating, etc. its still gets pretty cold outside and i have not experienced any negative effects of disabling the fitv. if you search forums, most people will say no to bother with it or its not worth it. i did it no probs. if you still decide you wanna disable, heres the link:Prelude Idle Air Valve Bypass Procedures

keep in mind this link mixed up IACV with the thermo valve so the link above is actually correct. i used that very link to do mine. easy stuff. i didnt even remove my throttle body. i did it with the tb still on the car. you may wanna remove your tb since you may be drilling the jb weld out.

batcave00 · 03-12-2010, 04:39 PM

i did something similar yesterday, but i just put an aluminum plate to cover the three ports on the bottom of the thermo valve. and i bypassed the coolant lines. the lower port however is still closed, and my iac is unplugged. its idling ok now, but i now have a CEL for the aic. wen i connect my aic, the car revs up quite a bit. should i still plug it in and remove the JB weld? by the way i also cleaned my aic, but it made no difference, possibly because its using an incorrect seal...it was 2 rubber circles. instead of the one that like like an 8.

dontbuyprelude · 03-12-2010, 05:50 PM

i would plug in the IACV and drill out the jb weld.
honestly i cant remeber if the IACV uses 2 circle seals or a 8 seal.
only do the idle adjustment if the idle is steady when you connect your iacv.if it still bounces then you got problems.

there is a procedure to lower your idle. i would lower it to about 750-800 rpm bc that way you can cruise parking lots in 2nd gear without stalling.
im doing this from memory but it should be an accurate guide.

To Lower Your Idle RPM:
1. unplug the wiring connector for the IACV
2. let the engine warm up to operating temp and have the fan turn on once. (when i adjusted my idle i drove my car hard around the block to get the fan to come on)
3. on the throttle body, there is a screw that adjusts idle. turning clockwise increases idle rpm. counter-clockwise lowers idle rpm.
4. wait a minute for the idle to stabilize
5. adjust idle again if necessary
6. wait a minute then reconnect wiring.
7. Hope your idle is good