2kej6

hello civic forums.
I am not usually the one to post asking questions. Usually just search the threads and then YouTube/google...after exhausting almost every forum search and amazon/AutoZone overnight parts I've given in...I need some advice/help before my final attempt tomorrow (later today its 0202)

The car is a 2000 civic lx sedan auto mods are I.H...its awaiting a nice fresh motor but seems to be falling apart little by little, first the trunk leak, then door leak, head leak (still sealed surprisingly) cleaning up rigged wiring etc. I cannot pinpoint when but about two weeks ago I experienced my first idle surge..it wasn't your typical surge. When started cold had a perfect idle, tone, overall healthy vibe to it. Then, 0nce warmed up - gradually ill see the rpms rise and fall until its full blown surging and I'm having to half way smash on it every time I take off from a stop to keep it from bogging down.. once I pass maybe 2500+ rpms its completely fine. stop put it in P or N and rpm raises then begins surging again...so after plentiful research and $$ spent I've come to my last conclusion and project for today...Intake manifold gasket. Before I explain here's what I've already done to try and fix this:
1. All hoses checked and besides some weird routing no leaks
2. 2 PCV valve replacements
3. new fuel filter
4. new evap purge shut off valve
5. coolant temp sensor with thermostat
6. IACV clean
7. IACV replacement
8. TB clean
9. Several adjustments on TB and accelerator cable - I know..
10.trasmission flush
11. coolant burping (maybe not to standard)
12. several idle relearn attempts (all rushed..)
13. new battery (bad cell)
14. new alternator
15. 2x valve cover gasket with spark plugs + wires (ngk) replacement
16. countless useless additives

After todays "diagnosis" after research and buying a 120$ OBDII reader I popped P0505 and P0509 along with my missing 02 due to the header..
Its all IACV related BUT I have noticed from day one my intake manifold gasket was garbage...too the point I sealed the gaps with exhaust paste. Again horrible idea but at the time was desperate..so unless I come up with a new final solution later today I have a fresh intake gasket, coolant, and hosing. Going to install the intake manifold gasket after cleaning off all dirt and exhaust glue...find the correct routing for vacuum lines. then do the proper idle relearn. proper coolant purge according to the Haynes manual...also battery will be fully disconnected and 15 fuse pulled.. if that doesn't do it...I'm not sure...ill take it to a shop. Need it for another month or so then it'll get a new motor/trans

my main question is how do I go about "resetting" the TB screw/accelerator cable back to a starting point? This way I know where I'm adjusting from etc.. ANY HELP/INFO appreciated....to whoever read this especially at this time.. thank you. Will post an update later today...need some sleep

Pictures

https://drive.google.com/drive/folde...U0?usp=sharing

ezone

Aftermarket parts may not be correct, may flow too much and cause idle problems as you described. Watch out for it.

P0505 is simply a wrong RPM that the ECM isn't able to control correctly for any of several possible reasons.

P1509 is a circuit code, you need to figure that one out before doing anything about messing with trying to adjust idle rpm.

Aftermarket parts are a crapshoot (so are used parts). There may be several different versions of the IAC depending on which engine type you have and which transmission type you have. A wrong part may bolt in place but not be right electrically.

If you never touched it, it may not need anything..
If you fix all of the other obvious problems first (the fault code and the intake gasket vacuum leak problems), it may not need anything other than a relearn.


If you touched the big screw and didn't note the start point so you could put it back where it started, you shouldn't have done that.


If you have everything else on the engine corrected and operating as it should..... and you still have idle problems, then the IAB screw adjustment might be necessary.

I'm used to a scantool that does the setup and monitoring of the process.....but I might improvise a setup something like this:

Clean the throttle bore and plate of carbon buildup.
Clean the passages for the large screw. If they are clogged up, adjustment may not be able to do anything.

Reassemble, install, run engine and get all warmed up to operating temp.

Use your fingers to block the air passage in the side of the throttle body that lead to the IAC valve.....
Now adjust the big screw to obtain the spec idle RPM.

2kej6

Hey, I appreciate it! getting ready to start on it now..

2kej6

DAY 1 of my final attempt at fixing this idle issue before...I send it to a shop... so here was is/ plan of attack.

battery completely disconnected with the underhood 15amp fuse pulled (Haynes says its 7.5?)

cheap intake removed

coolant drained

and the dismantling begins....

https://drive.google.com/file/d/0B_t...ew?usp=sharing

first area of concern for me is when I pull fuel rail with injectors. They are nasty...being on somewhat a time limit I do a quick wipe and keep on

https://drive.google.com/file/d/0B_t...ew?usp=sharing

I start to see the pcv valve, check it - its not rattling...add that to cart on autozone app...some of the lines are routed wrong = different hose types, clamps etc...so I figure undo it all clean it up and begin fresh..since I'm in the area of one of the grounding points at the thermostat housing why not change it out as well...when I go to pull the bypass off it tears into two pieces

https://drive.google.com/file/d/0B_t...ew?usp=sharing\
https://drive.google.com/file/d/0B_t...ew?usp=sharing


so I add a new bypass hose to the order and determine majority of these lines are going to get replaced...

at this point I take a break for other obligations and to pickup my order of a new TB gasket, thermostat/gasket and plenty of hosing...oh and a scraper for the old gasket which took at least an hour to fully clean/prep... now its getting later and I decided to get the manifold back up/torqued for the night and pick up again tomorrow..commected pcv with new line and original Honda clamps. as well at the middle S looking line....I end the day with this view

https://drive.google.com/file/d/0B_t...ew?usp=sharing
https://drive.google.com/file/d/0B_t...ew?usp=sharing

with the intake gasket on and manifold torqued along with the TB being cleaned and remounted on fresh gasket I quit for the day....I do have a genuine Honda accelerator cable because mine is frayed pretty good,,,FedEx says noon tomorrow...hopefully can finish routing lines correctly fill/bleed coolant & a PROPER idle relearn...

anyways, saw at least two reasons for the idle issue...horrible lines/connections...and dirty fuel injectors/ports??
Also wanted to ask before reinstalling the rail...is there a way to manually quickly clean injectors? didn't want to spray the wrong stuff and ruin them and I don't have time, or $$ to buy the cleaning machine..so for now I wiped off the grime...

again any thoughts ideas etch always welcomed!!

ezone

Injector crud is normal. Wipe off if it bothers you, and reinstall.

2kej6

To whomever is still following this thread...today I got the manifold back on. my new throttle cable showed in the mail finally so it went in...reconnected everything with new hosing etc and original honda clamps...started up first try purrr'd beautifully while i started bleeding the coolant...sat back and thought "nice - done.." then slowly and i mean veeerrrry slowly i notice the rpm is raising and slowly lowering...$@%($$@
agggh!! so i find a steady rpm to hurry this air purge and the surging stops momentarily and then comes back. My idle screw was removed and cleaned prior to reinstallation so i have no idea on where it needs to be i tightened all the way down before start up...then for some reason I covered the port next to the TPS and the surging stopped, the idle lowered...and evened out... perfect...so now my thought is TPS is bad....between a LOT of air in my system and tps I believe its solved...i bought a tps just in case for the AM and tonight ill research some more about it...so close..



https://drive.google.com/open?id=0B_...1RsTUJQWVVNNWs

https://drive.google.com/open?id=0B_...1pmRnV6czVaaVk

https://drive.google.com/open?id=0B_...2gzMUxabnNNTlk

ezone

It's not a TPS problem.

The open port you circled leads to the bigass screw that you keep asking about.

Cover the OTHER port (leads to IAC valve) and see where idle RPM goes.
No change?
Keep this IAC valve port covered with your fingers and run that bigass screw down until you reach the idle RPM specification.


Bigass screw will probably need run in all the way to til it hits the stop then back out somewhere around .5-2.0 turns to reach idle spec

2kej6

Will try 1st thing once I get up...kind of hard/pain to bleed coolant while trying to correct surging issue...assuming you're right then that's 50$ back for me... 😀

Also..during the slow surging I unplugged the IACV connector remembering that if idle levels out IACV is bad or is it the other way? When I unplugged it it surged even faster Also..this IACV was literally replaced 3 weeks ago..

2kej6

EZONE you are a genius....im sitting here 20min in at an idle rpm of 930-37....not one miss...never heard it sound so smooth and quiet....not calling it fixed yet though I will call it finished when I drive the 50$ tps back to AutoZone hahaha

ezone

Your idle RPM spec should be more like 700 (actual spec may vary a little depending on engine and trans and location). Reset and recheck.
The spec may be on an emissions sticker on the hood or in the engine compartment

Then after the hot idle RPM is set, make the ECM to do the idle relearn.

2kej6

https://lh3.google.com/u/0/d/0B_tp2U...260-p-k-nu-iv2

ezone

403. That’s an error.
Your client does not have permission to get URL /HPjnAodvyrCxj-u0mYgTX9_hdiuAj_l9EVBlqtAF1e6k-FB3QuCXnbwMIHAsfIZL7TbBcw0mhdG0_QRG1h2fwr1CorJkNMz jKy-AGikW0H_UViP9EGgA_8kAm9qN60u0G278aOzBehOtwghtvqQKN A-D8HT6Erk-82wJmGySK7gzp_tHuDmVoXy5uz5fXl1Dj9JniOO6PM7lCgkjNr ldgORske_r2f9d-Dei3R-Px4HYUU60GdRplm2NfJM0beBQs4KPaLWvaFk7-acLAG9jptHC4-mXZln2ctx0vrRCBtbydOeYLXYQiyP6Gp2c_GScXAfxEhcnrSKV VOD2Bfyw1b671PLj8dc7j7So8pdRwkYW5griotI7xXhHA49rgP ovZHZtIpIC6Qi43Y_rjFWWb2jf283kyw20Um-HeQoS0mwSTFEhvalBFtU0DqlGkiVPqlzFL9IyMtHdNUhyut7E8 bz_JD0OSq4XA21vKxfqrNOL3Gr2aN2iBzyrPP6xt9x_budMGgl FIjHjKecOLutewerm_nlheTXMaLItwoZxbdJSSC7DsGKcIpwCo 3eEE9Swd1QahkLQ=w348-h260-p-k-nu from this server.

ACL Denied That’s all we know.

2kej6

sorry about the last post..it was an attempt to upload etc from the cellphone..here's the first startup video about 3 hours ago now...i've since lowered it down to 870 and that's as low as i can seem to get it...that was me sinking the screw down IACV plug off, adjusting screw, replacing connector until rpm sound and reading from OBD2 live reading were satisfactory...when i change gears the rpm doesn't drop TOO low to where it shudders etc...few more pokes, and prodding and its ready for a test run tonight

https://drive.google.com/file/d/0B_t...ew?usp=sharing

ezone

If it's not surging now, that's good.

I hear hissing in the vid, is that really some vacuum leak, or just noise in the mic?

2kej6

No surging yet...so far so good

2kej6

Alright update
video explains most of it
I'm bogging/stuttering under light throttle low rpm. I have to smash on it to make it run right...highway speeds are fine. Iacv replaced in Nov. T.v. cleaned etc....

https://drive.google.com/file/d/0B_t...w?usp=drivesdk

ezone

Got codes?
Did you ever jack with the throttle stop adjustment? (big no-no)
Did you ever jack with the TPS?

What does your scanner read the TPS voltage as at closed throttle?

2kej6

throttle stop..as in the Smallest screw no - never touch it

codes yes same Ho2s (s1) heater failure
h02s b2 s1 heater circuit malf
a/f sensor b2 s1 malf

TPS i want to say had reading of 9%

and open loop fuel sys - sensors i guess?

ezone

O2 sensor failures can keep the system in open loop......that could be making it run funny. Might be a good place to start, but sure can't tell if that's the entire problem though.

What are the fault code numbers? (in the "Pxxxx" format)

Did you ever try to adjust your TPS?

I was trying to figure out if the (video) tach quivering while driving might be associated with the idle surging...damn hard to tell from just a video.

Can you backprobe the TPS signal wire to see a true voltage? (volt reading on a DVOM instead of % reading on your scanner) Looking for target of 0.49v at closed throttle.

2kej6

i will double checking some wires. then going to start up...cold start sounds beautiful even drives for 20min or so then while stopped its almost like another load is put on and it raises the rpm to 1500 and from there the bouncing. going to check some connectors and go for drive with scanner attached to record

Wankenstein

When you replaced the IACV did you replace the rubber gasket too (looks like an 8)? If not, that gasket can flatten out and not seal properly allowing a small vacuum leak.

This read may help: http://www.preludepower.com/forums/s...d.php?t=211317

ezone

^Some IAC designs also expose coolant to leakage if the gasket fails, both external and into the intake

2kej6

The problem solved itself with a new manifold...from a y8...?? Idle is now 745...doesnt fluctuate, little more bottom end torque....randomly picked one up from pick n pull and decided to swap out that whole mess...

Carluck

Just wanted to throw my two cents in about my experience in case it may help anyone else. Or correct me if I am wrong. I couldn't for the life of me get my car to 1) with old iacv it would crank and do ok but after warming the car idled low and it sputtered here and there. Car would stall every time you tried to start after it was warm. 2) with the new iacv it fluctuated idle like crazy but other than that drove fine. I followed the procedure for idle relearn every time I did any adjustments but no luck. Finally I noticed a set screw with a pentagon shaped bolt on the side of the iacv itself. Thankfully it wasnt hard to turn and I did so two or three full turns with a phillips screwdriver. Did the idle relearn and the ran and idled great. Thing is I couldn't find any info on this at all. It was a pure fluke that I even decided to turn it at all but whatever it did my car runs great now. Thanks to all who have posted info though it has all been a huge help.

Steven Aldridge

ezone ..are you eric the car guy?

ezone

Nope!