Im having a fluctuating idle problem that mostly happens on hot days and sometimes at night if I drive the car for a good while...The problem is when I press in the clutch the motor revs past 2000+ on the tach and won't go back down to normal unless I press on the gas pedal.

Even when im shifting through gears the idle doesn't drop and keeps reving high...When im coming to a stop and throw it in neutral the idle shoots high also...The only thing that brings it back down is when I give it some gas.

This problem comes and goes when it wants...I can drive the car at highway speeds on the freeway and then the problem goes away if it was happening at stop and go traffic.

I also notice that my temperature fluctuates from cold to normal but has never overheated...The temp will take a while to go to normal then drop back to cold then creep back up to normal if it has any relation to the first problem...This usually happens at night but quickly goes to normal temp in the daytime.

zc sohc w/si tranny
d16a6 complete intake manifold
mpfi conversion obd-0
pm6 ecu

 

check and make sure your throddle body position sensor is tight becuase it that sensor can turn a little and mess with the reading its getting and as for your temp issue either a sticky thermosat or needs more antifreeze check those and let me know what happnes

 

tps sensor is tight...antifreeze is full...haven't replaced thermostat yet but it's practically a brand new gates one with 7k miles only...just loosened up my throttle cable and changed out my iacv so im hoping for a fix if not ill change out the thermostat.

by the way not getting any CEL or any ECU codes.

 

And the system was bled? Air pockets can do this as well. It's not the TPS as you didn't mention dead spots in the throttle. Also don't rule out a coolant temp sensor that's on it's way out. Whip out a multimeter and test that as well.

 

I agree with the above poster,air pockets in the cooling system could cause this and possibly a bad temp sensor.

 

are you guys referring to the temperature reading problem or my erratic idle...!!!

 

so i just drove about 80 miles and the idle was perfect and the temperature gauge just stood at normal temp without fluctuating up and down...i guess the true test will be during daytime driving...!!!

 

Hey carnal, Also make sure your clutch cable is not rubbing or entangled with the throttle cable.

 

Maybe a sticky throttle cable for the idle problem??? As for the coolent temp maybe a loose connection, or the temp senosor is on its way out

 

check your throtle cable if its sticking. also a coolant temp sensor could be bad making the car idle high, and change your thermo and check your coolant temp senderr for the cluster bro.

also what kind of cable are you using for the throtle????

 

if you want ill drop by your pad to help you out tomorow is day off i should be able too bro

 

Sensor not sender - two different things.

 

I have a 90 HF mines a 1.5 8 valve... Ive been wanting to add real mods so it can run a little more.. so far I just have a cold air intake and full exhaust system icluding headers... just wondering if theres any suggestions on what else I could add... (some cheap/effective mod's??) :/

 

you can start off by creating your own thread.

update to this problem so far so good...hasn't made the erratic idle since my adjustments last week.

 

So the IACV fixed your prob? My first guess with a 2k idle was going to be a vacuum leak somewhere. If it happens again, go to work with some carb cleaner on the running motor around the IM, see if it jumps.

 

cant say that it was just the iacv since i also adjusted the throttle cable as well...no vacuum leaks either and the car has yet to idle high...keeps fingers crossed...!!!

 

My b18b did this a few days ago to. It ended up being a combination of a vacumn leak going to the MAP sensor and the throttle cable being a littlle too tight.

 

thats some "pan"dulce on your avatar BC. Glad your idle is fixed.

 

i only represent the best carnal

just replaced my gates thermostat with a oem one i had laying around...**** idles firme along with hot air and my fans come on perfect...still no unusual idle