rich idle, lots of questions, and beg for mercy

[the_momo]

as it states.

rb20 in s14. i have stock injectors for an rb20 (thanks rbspitfire) in my automobile...my plx says its at 14.7 when i first start it then it gradually drops and idles rougher and rougher the richer it gets. does it without any input from me (it makes its own decisions apparently). itll go to below 10:1 and it just says rich.

what i have.rb20. lots of prior hacking. the car was originally run without the iacv, the throttle was opened a little. it idled at 11.7:1 with 550cc rx7 injectors and a blow through gm maf but it ran.

it currently has a stock blue label (cant remember number) maf (its actually not from an rb20, but i cross referenced the numbers and the one i have is the same pn.)maf is draw through. stock injectors and stock ecu. the car starts and idles the same way every time. no trouble starting and eventually descends into being rich. wouldnt it be nice if it were that easy.

i fixed all of the wiring that was modified back to factory. the wideband o2 sensor's output to factory ecu is usedit has one of the large plenum intakes (prob ebay junk, came on the car) with only one vacuum port. it does not have from what i see an aac valve/sensor, the one with the 2 wire brown plug.

things that werent used on prior setupcoolant temp sensoriacvaac

there is no aac, the iacv was not even on the motor, and the coolant temp sensor was in the center console. where does the cts go specifcally? (i have it in a water line as of know but i am sure thats not where it goes (i have metal water lines, yeah, not my work, dumb idea, gonna change soon)where could i get an aac cause im sure i need one.i have good vacuum(18-20) but could having the iacv in the same line as other vacuum lines make a difference? ive done other cars like that and it wasnt an issue.(iacv goes charge pipe-iacv-intake manifold)and lastly does anyone have any other ideas i can try to get it working?

so thanks for reading i know this is a reallllly long post but i am giving as much info as i can. i know some of you are wanting to me but this is my first rb and i bought the car swapped and modified. my mistake i know. most of what i have found for troubleshooting my issues has gotten me to where i am, better than i started but not yet finished.i get no codes other than the uncertain girlfriend code 55 "oh everything is all right....liar. any and all input is greatly appreciated, and thanks a bunch in advance. sorry again for the mega post
Modified by the_momo at 8:33 PM 11/27/2006

[Bluefire]

Ok first make sure the maf you have is correct, this can easily cause a rich lean condition. Second i'm not sure from what you posted but make sure the factory O2 sensor is hooked up and functioning. You use the wideband O2 as an auxiliary sensor not a replacement. Third make sure your engine temp sensor is hooked up(two prong sensor). If this isn't functioning correctly it can make the engine run rich and idle rough as it warms up(Incorrect resistance values for the given temperature). fourth make sure the iacv is hooked up correctly (ign on one side/signal on the other). Your ecu needs this to adjust idling situations.

-Bluefire

[the_momo]

ok this is what i have thus far..

the plx has an output to supply factory narrowband signal to the ecu, but im gonna put in a normal 02 (one i had from my ka24, see if it makes a difference)the cts is hooked up (yellow two prong plug in coolant line, i dont have a factory intake manifold and no provision for the sensor in the coolant line...yeah) conna take it out and clean it or try to find a replacement if necessaryiacv is plumbed as such. charge pipe (pre throttlebody)/ iacv/ intake manifold. i have the end with the electrical plug as the input (charge pipe to iacv)the maf i have is pn 22680 16v00 a36-000-n60, it has a dark blue label and i have seen it referred to on the r31 skyline and a31 cefiro.i have seen the rb20 maf with a light green label and pn 22680 02u00 a36-000-n60both are for the rb20 and have identical plugs. would it make a difference from one to the other? or more importantly to make it run horrendously rich?also, i have a downpipe only, its about 2 feet after the 02 then it dumps, but ive had a similar setup on my srt and it made no difference, but would that matter in this case?

tomorrow im going to check spark plugs (gapped to .8mm) and replace if necessary, check cts and wiring and check tps/adjust if necessary.

lastly, from what i see, i dont have the aac? the gold small canister on the back of the intake manifold near the firewall with the brown plug. anyone have one they would be willing to sell? im sure this would make a difference, or is there any way around using one? just more and more it seems the more i work on it. thanks again for all the input. sooooooo close. tomorrow also ill post up current pictures so everyone can have a visual of what im working with. then yell at me accordingly. id rather be yelled at and informed than just play the guessing game forever. thanks again.

[the_momo]

anyone? i really could use some light shed on this, at least about the maf sensor.

[digzsublime]

I am running my rb20 without the AAC hooked up and am having no issues from it.

[FAST-DATSUN]

your computer can not read the aftermarket wide band o2 sensor!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

[Yellow4g63]

I know my wideband has a analog output that you tap into the factory 02 sensor at the ECU and everything will be happy. I say just leave the wideband in and hook it up right. Your car will run rich with a bigger fuel pump and factory FPR. You can always turn the boost up lol that will lean it out.

[Blown240sx]

What?

Some very bad advice going on here.

The PLX sends a reading to the ECU so that not the problem.

Also turning up boost to lean out mixtures..... WTF?

Lastly how far is your MAF from your turbo inlet and is it bent at all or straight pipe? Pics would help.

[rbspitfire]

throttle switch, it should be 10v at idle, check it i bet its at 0. mine had a loose connection when it was at 10v it was normal as soon and the connection would loose contact, it would start puffing black smoke, running rough, and even fouling plugs.

[the_momo]

didnt check the throttle switch yet, but i do have continuity when its closed...the maf is about 12" from the turbo, before, and 90degree bend. same intake tube i used on my ka-t, worked fine.the o2 sensor output works fine.

heres what i think....the coolant temp sensor is in the coolant tube. the intake on the car doesnt have provisions for the cts. im guessing if it isnt threaded into something that would give it ground (like the factory setup is) yeah i know confusing. heres what i have rubber coolant tube-metal elbow(with cts)-rubber coolant tube-intake manifold. im gnona try to ground the metal elbow the cts is in to see what difference it makes.checked all of the wiring and all sensors have continuity to the ecu. this is getting ridiculous.anyone want an s14 with an rb20?