extremely high idle

[bonestock240sx]

cleaned the IAAC valve. no change. so my dad and i are going to pull out the voltometer and check all the wires. we found that the tps wires have already been checked so this problem might have happend before. uh oh. someone lied to us.

[jetroy240]

Usually it will give u a tps code if there's a problem there. To erase code, just turn the small screw clockwise w/ ignition on & read the red flash, one flash, then 2 flash then one flash then turn the screw counterclock wise, then turn off ignition. I f code 12 come 's back again, it's time to do those voltage checks.

[bonestock240sx]

i already erased all the codes. code 55 flashes which is the everything is all cool code. but everything isnt all cool. and when we wiggle the TPS plugs the idle drops, and same with wiggling the MAF wires. so we will see what happens. but ever since i changed the o2 sensor its been "hunting" pretty frequently

[jetroy240]

the good news is you have a code 55 w/c is normal operation code. If that code 12 is a hard code, it will come back right away even just key on engine off & key on after erasing the code. I would let it run for a long time & check again the code 12 if it's still there.

You can adjust the idle now at AAC valve, warm-up the engine, disconnect the connector at AAC valve and adjust the screw to set your base idle, then reconnect connector after you reach your desired idle rpm.
Modified by jetroy240 at 3:33 PM 2/5/2009

[bonestock240sx]

Last night we checked the TPS, MAF, COOLANT SENSOR, and something else i dont remember. but we checked all those and they were pretty close to specification. the tps was reading .77 and we adjusted it down to .44 at idle. so yeah then we found the distributer was advanced to far and we retarded it all the way and that brought the idle down to 1000 but now its extremely sluggish and doesnt get up and go anymore. so i think im going to adjust that back. it just doesn't seem healthy for the car. i can't even brake the tires loose now. disgusting but thanks for all the help guys
Modified by bonestock240sx at 9:26 AM 2/6/2009

[jetroy240]

ignition timing will be advanced if u check it w/ idle so high, u gotta fix the high idle first. There's an air regulator valve that bypass air when it's cold for warm-up mode. If this is always open, idle will be high. Check the 2 terminal connector, probably corroded. To check the circuit, one terminal is 12 volts w/ KOEO (key-on engine off) or KOER(key-on engine running) & the other terminal is ground. What this air valve do is by-pass a large amount of air into the intake manifold when engine is cold after start-up for warm-up mode that's why idle is always high when cold. Then slowly closes as the engine warms-up for a period of time at the same time lowering the idle. This valve is normally open when cold, it's uses a bi-metallic plate w/c gets it's 12 volt supply when fuel pump relay is energized.To test it's operation, u have to remove the air regulator valve from the intake manifold, and visually look at the hole & watch the bi-metallic plate close slowly while supplying 12 volts & ground to the terminals on the bench. Should be open when cold ( no voltage supplied). Common problem is stuck-open.

Just make sure u don't have a large vacuum leak , before u check this air regulator valve. Spray the intake manifold gasket side w/ carb cleaner while idling, topside & bottom-side, to see if there's any changes in idle.Good luck.

There's a good possibility that the bi-metallic plate of the air regulator was warped after spraying thru the maf. You probably just created that code 12 by unplugging the maf w/ KOEO or KOER.

[bonestock240sx]

where do you get all your info from. ha cus you got a lot of it. but yeah i squeezed the air regulator hose last night which is what is says to do and the idle didnt change. so what does that mean. and yeah i figured as much and im going to advance the timing back. but my dad said the timing was 40 btdc

[bonestock240sx]

o and the 40btdc was advanced and bad my dad said thats why he adjusted it down all the way to get normal. but last night we got the idle down to about 1300 after lots of tinkering then thats when we retarded the timing. the only thing we didnt check is the IAAC for any resistance or voltages cus it was late. so i think tomorrow that might be on our agenda.

[jetroy240]

You did not crack the hose of the air regulator valve did u?, Usually they are very hard & brittle if it's still the original hose. If the crimp is good, & the idle did not go down, it means u can rule-out the air regulator being faulty. Try to crimp the brake booster hose, see what happens. Is the distributor removed prior to all this? How's the intake manifold gasket? This is the most common problem of this engine, the intake manifold gasket near the no. 4 cylinder intake port always leaks. Spray carb cleaner under the intake manifold while at idle & see if the idle rpm changes. If it change, it means u got a leak there. Just watch-out not to spray at hot areas like the egr exhaust pipe, might cause a fire.

[bonestock240sx]

mmm i love fire. no its not cracked. and ight ill just start spraying around and see what i can hear. we will see. yeah i def need to advance the timing back my car feels like a honda HAHAHAHAHAHAHA

[jetroy240]

I'm beginning to think that you're the one who swap the honda engine to the s13?

You know where I get my info? at FSM, I'm just reading it back to you. Hahaha!

Tps connector should be disconnected when adjusting timing, engine at normal operating temp., idle at approx. 700 rpm. Timing should be at 20 degrees BTDC at Neutral(for A/T) . A bad tensioner or chain will cause wrong timing too. No chain noise at first start?

Modified by jetroy240 at 9:15 PM 2/6/2009

Modified by jetroy240 at 4:43 PM 2/7/2009

Modified by jetroy240 at 4:44 PM 2/7/2009
Modified by jetroy240 at 4:48 PM 2/7/2009

[bonestock240sx]

haha why would i put a honda engine in my s13 yeah right. what a joke. however honda's are mean little snow fighting machines i had one before this car. it used about 4 qts of oil on a good day (cracked head) haha. anyway yeah i downloaded a full service manual that has like all the actually good procedures, not the stupid chiltons one which has almost no information. anyway. so back to the car. when i got the car the timing was about 40 degrees BTDC and it ran perfectly fine, very torquie, but when i adjusted it back to 20 BTDC it was really slow and had no power and i felt like i was in a higher gear. example i was in first it felt like i was in 2 and so on. but i adjusted it back to where it was and its like wonderful, but the idle is still high. so yeah im still at square one just have ruled out a few things.

[jetroy240]

What's ur findings on the spraying of intake manifold? & crimping of brake booster hose? Throttle body gasket ok? Any cracked vacuum hoses?

[bonestock240sx]

i haven't tried it yet but i will within the next week

[Morpheon]

dude if its still idleing high pull ur egr off and make a block off plate i got a 98 240 and mine did the same thing.

[bonestock240sx]

or not and just get it fixed cus its not the egr. and jerry rigging stuff is dumb. but thanks for the idea. ...... tomorrow im taking it into my buddy who was formula d driver and a specialty mechanic on these. ill let you know the findings.

[g35paul]

love to see what he finds out cuz mine does the same thing ur is and ive checked bout everything.... was bout to take off egr, plan on building and going Ka-t anywyas...

or not and just get it fixed cus its not the egr. and jerry rigging stuff is dumb. but thanks for the idea. ...... tomorrow im taking it into my buddy who was formula d driver and a specialty mechanic on these. ill let you know the findings.

[ReX2SX]

Dude, diagnos stuff dont throw parts at it. So i will give you a list of things to check that can cause high idle, some of the things may not pertain to the vehicle so bear with me lol.

1. TPS (you said was good)2. Vacuum Leak -EGR (if vacuum operated) -Intake side - Fuel pressure regulator (if equipped)3. Bad 02 sensor4. Exhuast leak before 02 sensor5. Bad coolant sensor6. MAP sensor (if equipped)7. Incorrect igntion timing

Just make sure you have air going smoothly into the engine becuase if you have the timing advanced then it soudns like your running rich.

Thats all i cant think of off the top of my head

[bonestock240sx]

i have already checked the tps, changed the o2 sensor, changed the thermostat checked all the wiring. and vaccum leaks wont arise from spraying cleaner through. if anything it would clog something up. but the computer said MAF but i think that was from when i was messing with it after i sprayed that stuff. cus its not there anymore. the timing was supposedly advanced, but as of today when i took it to my buddy he noticed the the pulley that has the notches, on the bottom of the engine(Harmonic balancer???) where you can see what your timing is set at..... well that was spinning around which isn't good since it is supposed to be stationary, and also has of today my started went bad. so yeah i will probably no by tomorrow i hope.

[bonestock240sx]

well guess what it is.... TPS he is 99% sure its the tps. because he checked it today and it reads what it should when the throttle plate is closed but when it opens it doesn't read anymore (doesnt read past 2 k ohms) so yeah. well i will get one in a day or two and we will see what happens.

[ReX2SX]

yay my numero 1, lol. Well i donty know Ohms values for it just volts. ~.4 at close throttle (idle) 4.5 WOT

[bonestock240sx]

yeah in ohms its supposed to be 2 at closed 2-10 at partial and 10 at wide open throttle. mine just goes to zero at partially opened