Eddie 70

I just got through cleaning my throttle body, IACV, FITV and replaced my TPS. I did this thinking it might help with my problem. The car wants to buck at around 1500 RPM. I adjusted my TPS to get 4.5V at wide open. It is at .50V at closed throttle. With the car running, press the gas pedal down easily and slowly and the RPMS come up smoothly until around 1500 RPM then they stay at that point and bounce until I get the pedal down further then they jump up to around 2000 or so and then start jumping again. When driving the car in town around 30 MPH, if I am not in a low gear, 3rd or so, the car will really buck because it is around 1500 RPM. I have got to get this fixed it is making me crazy.

Do you guys have any ideas as to what might be the cause of the bucking.

Thanks for any help.

Eddie 70

There is no CEL on at this time.

MonkeyMagic

you are definitely thinking in the right direction. your iacv is not working properly. and has most likely gone bad.

if you unplugged it and drove the car you would get the same symptom.

EDIT: i had the exact same problem once. and man that got old quick. city driving was a drag.

Eddie 70

Is there a way to check the IACV? I cleaned it several times using the methods mentioned above. Its just a motor. Should be able to put some voltage on the terminals and hear it run, I am only guessing.

D Griff

I had a similar problem but I had an intermittent CEL for TPS. I replaced the whole intake manifold/throttle body, replaced the wires, even took it to a Honda dealer where they replaced the TB again with a brand new one (it was free so whatever) and none of these fixed the problem. What finally fixed it was unplugging and replugging in my ECU, it must've just not been connected well or something. Very weird I know. It seems like you're looking in the right areas.

farfrumugen

my buddies delsol does the same thing except his motor is the 1.5 non vtec. at idle if he revs it up to 1500 it starts hunting. does the same while hes driving it. he says he has traced it down to the fitv valve i believe. but he has yet to come over and get another one to try from my parts car. once he does ill let ya know how it goes if you havnt figured it out yet.
adam jeffery

Eddie 70

Were you guys able to figure out anything on this yet? I was going to take both of them back off of my car and check again.

farfrumugen

nope. he ended up selling it and buying an ej1. i can tell you we switched distributors and throttle bodies. neither of which fixed the issue. car had a full tune up with plugs wire cap and rotor...ect ect. not sure what else he did on his own
adam jeffery

adgarland

my d15 del sol is doing the same thing anybody knows anything about it thanks

qharr1

My del sol does the exact same thing!

I went into a mechanic, and they put it on a scan tool... it read that the iacv failed.
i pulled this off, and cleaned it.. Quote: i have cleaned previous iac valves before and the pin should be able to move freely IF! the iacv is still okay to use..

and its obvious now that i am going to say that the one on my del sol didnt even budge!
anyway in all atempt to fix this problem, i shoved it back on and no go!

If you plug the iacv valve in and detatch it from the the manifold.. it should start to work and youll be able to hear the motor..

I am quite convinced now that this might just be the cause of our problem!
I have cleaned my throttle body and retuned the TPS valve and nothing has changed apart from the fact that i runs smoother...

maybe be time to get a new iac valve!