Hi there, i have a 2000 lx sedan(tan) with a d16y7, giving a few issues. first of all let me introduce the vehicle

- Bone stock
- 91000 miles
- No previous accidents or collisions
- 1 owner since vehicle bought new in 1999 (i am second owner, bought the car 1 month ago, Nov 2012)
- Carfax vehicle report shows vehicle regularly serviced, and all/most oil changes have been done properly and on time as regular maintenance.
- Car shows no signs of underlying problems, is in great shape, and looks immaculate for being 12 years old.
I can tell the previous owner did take car of the vehicle.
no weird smells from the engine, engine bay clean, no rust, no weird sounds(except for minor brake pad squealing, and another sound i will explain later on)
Engine revs like a dream, and shifts so smoothly(its an auto... just saying.) it feels too good to be true. or so i thought...

Well heres my trouble. last week my father went under the hood, and gave it a nice little checkup, did some cleaning, added some clean oil and different fluids, changed wiper blades, spark plugs and wires. and also made the throttle a little smoother by tweaking the throttle cable<---(not sure if its actually called that, but it looks like a cable so ill stick with that name, lol.)
Also, he lifted the intake air filter housing, changed the filter, and also did some stuff with the choke and what not (mind you, during this part, the intake housing and filter were both off and the car was running. i wasn't too sure about what was going on with the engine, it sounded weird and wanted to shut off, i had to keep my foot on the throttle so the rpm's would stay high enough for the engine to keep running. also, i was smelling weird smells during this, and the strangest ugliest noises were coming form my engine (im guessing this was because of the housing and filter being off?), well needless to say my father said all that was normal, and not to worry. so i didn't really worry about it too much (he knows what he's doing, i think..)

- well after all that, i started the car up and the check engine light was on. not sure what the actual code was, but it was for unstable RPM.
well needless to say, we disconnected the battery, and cleared the code(the guy who read the code for us refused to clear it himself....)
and after that for about a week and a half the car ran normal, everything fine.
Well about 2 days ago, i drove into the driveway, put the car in park, **** it off, went inside the house (for about 3 and a half minutes) and when i went back to the car to leave again, the downhill spiral began...
- i started the car, RPM(idle in park) was around 3000(stable at 3000, not fluctuating up and down) and the engine light came right back on in that moment.
i turned the car off, kind of nervous, and then restarted it. it hesitated on startup, but it did start, and seemed as though it returned to normal(normal RPM, about 800-1000 idle in park) but now my engine light is on again, and im not sure what the problem was (i thought maybe a vacuum seal leak or something)
the whole way to my next destination, my car jerked every time it downshifted(thats the pattern i noticed). it was just a very scary and nerve racking jitter and thumping every time the car would downshift, i was actually very afraid to press the throttle

*i started to notice a weird sqeaky sound while the car was in motion, but the second i press the break the sound stops (this still happens, not sure what the sound is coming from) its an odd squeaky sound, that sounds like its coming from something within the engine, but it sounds like its rotating. its hard to explain.*

but anyways, back to the real problem... the code for the engine light this time was p0505, which is idle air control valve malfunction. i hear this is a common issue with hondas.
after that insident 2 days ago, my car hesitates to startup every time, and gives me a weird klicking sound when im trying to start it (takes about 3 tries to start it up) <--- thats my biggest pet-peeve.. when my car doesn't want to start. i hate the looks i get front the people are around me, judging me and my honda in their heads, LOL!
anyways, besides that the carseems to not respond so well, and seems like its holding back.

so basically, heres a few questions i have..
1- i really need help with the IACV problem, cant locate the dam thing! lol.
also i would like to know possibly some alternative routes to replacing the valve and sensor, its kind of costly to just replace them.
2- if anyone knows the sqeaking noise is, please tell, its so annoying (its very faint, but it bothers me so much)
3- the cleanup my father was doing under the hood, was all that normal? any comments on that would be appreciated...

Some quick relevant facts-
1- Old spark plugs replaced with Denso spark plugs (denso's are used with hondas im pretty sure)
2- when i was replacing the spark plugs, my old wires were busted to hell, so i just went ahead and bought all new wires as well.
3- my transmission bumps a little when changing gears SOMETIMES, not often, but is that normal just from age of the vehicle and wear and tear? or is there a problem in there as well?

Some things i should add..
- i redlined the car in an empty parking lot the day before all this, just for kicks and giggles. car still drove fine after that, and for the rest of the night (i didnt think i would have messed anything up doing that, i drove about 60-70 miles after that redline, everything was fine)
- i always drive windows down and A/C off.. just cause, RACECAR!.... and cause im a tool.
- i am a little heavy on the throttle sometimes...(most of the time) cause i like revs.... (*why?* cause RACECAR!...)

SOMETHING I JUST WANT TO ADD.. I HAVE NO IDEA WHY THE THUMPING/JERKING WAS HAPPENING, MAYBE IT WAS A ONE TIME PROBLEM, BUT CAN SOMEONE PLEASE SHED SOME LIGHT ON THIS. THAT SCARES ME!
IM WRITING THIS IN CAPS CAUSE ITS IMPORTANT. lol.

Also, im 17. and this is my first car.
and not to hate, i raced a 5th gen coupe(*why?* cause racecar...) the other day (RICER) and blew him away with my automatic bone stock sedan. yes, thats right... sedans unite! haters gonna hate.
Sorry for such a long topic

 

Absolutely too much reading involved here.

Could we get a summary with just the facts please?

 

Holy FRAT!
The IACV should be on the backside of the throttle body. If you google it youll find it.
For the transmission issue, when the last time you changed your fluid?

 

The IACV is attached to the front side of the throttle body. It has two coolant hoses running to it.

Remove the IACV and clean its sliding metal window and port with brake cleaner. Click the IACV link in my signature.

 

All the important stuff is in bold

 

I've tried to Google the issue but i keep getting results for odyssey vans, and other Hondas that arnt what i have, I just thought honda tech would be the one place i could get the most help.
I haven't even checked it yet, i suppose that may be an imortant thing to do, lol. what do i look for when i check it? could that be causing my jerking/thumping issue?

 

Thank you, that diagram is very helpful. i will definitely look into the link as well, thanks for your help!

 

i had a similar problem and i had no clue what it was so i took it to a local shop and it turned out i needed a new IACV.. that fixed the issue!! no more idling!!

Good luck!

 

Check the dipstick on the auto trans.
That surely could be the reason why it could slip or jump. Auto transmissions can get extremely hot and heat destroys the fluid's lubricating qualities and friction quality. If you dont have those the trans could slip/jerk. If you dont change the fluid it will slip all the time and when it slips its kind of like aggrivateing the transmission which makes it hotter and starts burning up internal parts. Which = no bueno