Need Some Help

[Stanlyz]

Hey guys. I need some help with my car.

what i have is:

s14 with a r32 drive train (engine ,trany,ecu mafs etc)

the problem i am having is that both of my o2 sensors are reading more than 2.5v and the car is obviously running rich.

(since its a project car and not an original skyline)

I do not have all the sensor connected to the ecu, like the exhaust temp sensor, and exhaust switching module that goes to the pin 32 on the ecu

so the question is what it does, and what kind of voltage does it send to the ecu, and do i have to have it (switching module)?

also i am running on nistune but have no IDEA how to tune the car

everything on the engine is stock besides : turbos upgraded to steel exhaust wheel, wastegate actuators are set to 7psi cracking 15 fully open, and hks boost controller set to 15spi

please, any help would be appreciated

[Room42]

I mean no offence but this post doesn't make a lot of sense really. I tried to get through it with thinking outside the square and this is what I came up with.

You said "mafs" and "both of my O2 sensors". That implies that it is an rb26.

A narrow band O2 sensor should read around 0.5 of a volt and vary up and down a few tenths of a volt. I think they max out at 1.5V or something. If an O2 sensor is reading 2.5 volts it is either a wideband sensor with controller outputting said voltage or a stuffed narrow band sensor. I've only seen narrow band sensors read a lower voltage when they are buggered.

Once again I'm not having a go at you but if you can't accurately describe the problem in a written format then it seems wiser to me that you take your car into a dyno shop. They can check the tune for you and rectify any problems or at least point you in the right direction toward fixing them. Just a quick check like this would cost less than $150.

[Stanlyz]

Right. that is exactly what i am talking about..

I know that ecu should supply some voltage for oxygen sensors (.4v) then the the ecu will use that voltage for the fuel trims + or - .3v .(with in 0 to 1v) Like i said I dont understand why I have 2.5v (oxygen sensors are new) the cars runs extremly rich 10.1

I dont have the switching module (I dont know what id does, and whats its there for, and what kind of voltage it gives to the ecu)

The problem about dyno shop, not a lot of people over here are familiar with nistune (the closest shop that does that, is 8hrs away) and i dont really what to drive the car that far, its going to have to be towed

[Room42]

I'm not sure what switching thing you mean. Pin 32 is for the engine check lamp. I have included a pinout map for you. I dont know a lot about rb26 wiring so you would be better off googling the answers you need. I am happy to help still even if I am googling them myself.

[Stanlyz]

the location of the module is under the passenger seat as far as i found (but i cant find any other info on the animal)

Edited September 30, 2011 by Stanlyz

[KiwiRS4T]

People could help themselves by putting their location in their profiles - that way they can better be directed to workshops or perhaps other members who might be nearby and prepared to have a look at the car.

I doubt that the O2 sensors are the cause of your car running rich. It sounds as though you need the help of a tuner unless you have a wideband some method of knock detection and know how to tune yourself.

[Stanlyz]

location is usa state mo

i have a wide band, knock detection assuming that the knock sensors work is done through nistune, but dummy me cant use the program cant seem to understand what to do......

[DVS JEZ]

Knock sensors in nistune are not reliable. So beware.

Leave the 02 sensors disconnected if they are reading incorrectly as they can cause incorrect fueling but ONLY at light load and cruise conditions.

U say its running 10-1? Do u mean at wide open throttle? If so this is normal for a stock ecu map.

[Stanlyz]

Knock sensors in nistune are not reliable. So beware.

Leave the 02 sensors disconnected if they are reading incorrectly as they can cause incorrect fueling but ONLY at light load and cruise conditions.

U say its running 10-1? Do u mean at wide open throttle? If so this is normal for a stock ecu map.

10-1 is at idle 1000 rpm (o2 plugged in)

if o2's are unplugged wide-band reads 12.4-1 at idle

your logo says you tune cars, want to give it a try???

Edited September 30, 2011 by Stanlyz

[89CAL]

sounds far to rich at idle thats for sure......

[Rolls]

Plug a consult in and see what sensors have 'failed' eg aren't plugged in properly etc. Coolant temp and O2 will certainly make idle rich, using custom piping for the AFM etc could also change the tune.

Once you have all the sensors sorted out perhaps getting some dyno time and someone to tune the motor might be a worth while investment?

An air leak is another possibility, can you get an adaptor and pressure test the intake?

edit: Also knock sensor failure will also do this, can you rev the motor? AFM or Knock sensor failures mean it will backfire and run completely f**ked as soon as you get any load into the motor.

Edited October 1, 2011 by Rolls

[KiwiRS4T]

10-1 is at idle 1000 rpm (o2 plugged in)

if o2's are unplugged wide-band reads 12.4-1 at idle

your logo says you tune cars, want to give it a try???

Contact Guilt-Toy on this forum:

http://www.skylinesa...1240-guilt-toy/

He has successfully tuned cars by remote over the phone lines e.g. a car in Georgia (the one in Europe) from Australia. He is currently in the UAE or suchlike. Ask him what is needed to make it happen.

[Stanlyz]

Plug a consult in and see what sensors have 'failed' eg aren't plugged in properly etc. Coolant temp and O2 will certainly make idle rich, using custom piping for the AFM etc could also change the tune.

Once you have all the sensors sorted out perhaps getting some dyno time and someone to tune the motor might be a worth while investment?

An air leak is another possibility, can you get an adaptor and pressure test the intake?

edit: Also knock sensor failure will also do this, can you rev the motor? AFM or Knock sensor failures mean it will backfire and run completely f**ked as soon as you get any load into the motor.

with consult cable connected i get a code 55 (no problem found)

I have a boost leak tester, i have tested for all the vacuum leaks and boost leaks (nothing to really worry about was found)

the engine runs fine up to a certain RPM or boost: it will run fine up 3000rpm (no back fires, no misfires) at that point i am at 7-10psi of boost, when the car gets to any higher rpm it starts backfiring through exhaust (farting) and loosing all the power at that time boost is at 10-16psi. so i am ether overboosting and the ecu is shutting the ignition and fuel off or i am running out of fuel and the car run way to lean (basically need to tune it)

[DVS JEZ]

Try new spark plugs. I use either bcpr6e or bkr6e. Both gapped to .8mm

Have u calibrated ur wideband sensor? 10-1 on idle doesnt sound right.

When it misfires it might show a lean reading, this is due to the unburnt oxygen/fuel mix. The sensor reads oxygen so if it hasnt burnt then theres is alot of it coming out the cylinder

[Stanlyz]

bump...

still looking for any info on exhaust temp sensor and the switching module operation on bnr32

[Stanlyz]

Thank you all for you replies you have led me in to the direction of fixing my problem...

fixed the o2 issue

further tuning on the car is performed by DVS Performance Tuning

Edited October 5, 2011 by Stanlyz