Jump to content
SAU Community

Recommended Posts

Recently done a bunch of upgrades to my 32 sedan and having some issues with the AFR. Was standard rb20det with just ISR exhaust, FMIC, and an op6 turbo until the seals decided they were done on the turbo. 
So I got a new gt2860rs, nistune (installed and tuned by rs enthalpy), deatschwerks 550’s, aeromotive fpr set at 45psi, walbro 255 , z32 maf, and aem UEGO.

Upon start up my wideband reads 14.7 but within 5-10 seconds will peg out to - - - meaning lean. I tried hooking the white wire (signal output) from AEM to the white wire on the o2 harness but it didn’t make a difference? I’ve also tried putting the sensor in the upstream (3” from hot side) and downstream (36” from hot side) positions with no luck on either? 

If it’s in the upstream position and under a lot of throttle it will richen SOME (16-17) but shouldn’t it be sitting around 13-15 at idle??? Have not tried driving the car yet to put it under load…

Am I missing something? Seems I’ve misplaced my old o2 sensor but should I just get another and resort back to narrowband to see if that fixes the AFR?

Link to comment
https://www.sau.com.au/forums/topic/483921-nistune-wideband-help/
Share on other sites

Have you set MAF to z32?
set injector size?

When I have used nistune, wideband is connected to the laptop via USB.
If can't connect to laptop put the sensor in the dump pipe bung and just adjust it reading off the guage.

@Dose Pipe Sutututu has more Nistune experience than me

  • Like 1

Depends on your AEM gauge, older ones has the option to simulate a 0-1V output which could be used to send back to your ECU for narrowband O2 feedback.

However needs to be noted, if the tune had the O2 feedback disabled wiring it back will do absolutely nothing. 

If your car is pegging that lean there may be another issue. You'll need to plug up and monitor the AFM voltage and TP Load and see if it's doing something weird and tracing into parts of a map that has been untuned.

I highly would recommend you bring it back to your tuner.

On 8/7/2022 at 9:40 PM, robbo_rb180 said:

Have you set MAF to z32?
set injector size?

When I have used nistune, wideband is connected to the laptop via USB.
If can't connect to laptop put the sensor in the dump pipe bung and just adjust it reading off the guage.

@Dose Pipe Sutututu has more Nistune experience than me

I sent Martin the list of parts I just mentioned for him to set the base tune parameters around that, including the wideband in place of the o2.

will need to find someone with a laptop and consult cable to check and see if that’s been done correctly. 

On 8/7/2022 at 10:17 PM, Dose Pipe Sutututu said:

Depends on your AEM gauge, older ones has the option to simulate a 0-1V output which could be used to send back to your ECU for narrowband O2 feedback.

However needs to be noted, if the tune had the O2 feedback disabled wiring it back will do absolutely nothing. 

If your car is pegging that lean there may be another issue. You'll need to plug up and monitor the AFM voltage and TP Load and see if it's doing something weird and tracing into parts of a map that has been untuned.

I highly would recommend you bring it back to your tuner.

I purchased the UEGO at the end of last year. The manual said white wire was 0-5v. I know the standard signal is >1v for these cars.

 

will have to find someone with a laptop and consult cable to check into the tune. Appreciate your quick replies. 
 

also it may be worth mentioning I have a standard fuel rail, one that came with a regulator on both sides. I replaced the one at the beginning of the rail with one of those ISR pass thru’s but left the one at the exit. Could this also be causing an issue or it’s unlikely to make a difference? 

Edited by Axt3365
On 8/8/2022 at 6:03 AM, GTSBoy said:

There's your problem. The stocker is not a reg, it is a pulsation dampener.

Meaning it won’t let enough fuel pass through the rail despite what pressure is on feed side? 
 

just ordered another to replace the dampener and see if that makes a difference. Thanks! 

Edited by Axt3365

Another thing that comes to mind, have you given the fuel pump full voltage and bypassed the stupid factory drop resistor?

Easiest way to just connect the pump's -ve from the fuel tank lid direct to chassis to bypass the FPCM/drop resistor.

Is your fuel pressure respecting the requested pressure + manifold pressure/vacuum?

On 8/8/2022 at 6:53 AM, Dose Pipe Sutututu said:

Another thing that comes to mind, have you given the fuel pump full voltage and bypassed the stupid factory drop resistor?

Easiest way to just connect the pump's -ve from the fuel tank lid direct to chassis to bypass the FPCM/drop resistor.

Is your fuel pressure respecting the requested pressure + manifold pressure/vacuum?

I have not bypassed it, just connected back as factory fuel pump was. I’ll try that this evening. 
 

the gauge on FPR is holding steady @ 45psi 

Edited by Axt3365

RBs are tough little things, to rule out any air leaks through the hot side, I suggest just take the car for a gentle drive and gentle load it up till close to 100kPA aka 0 psi for you Muricansssssss.

See if your AFR readings are somewhat richer than stoich.

I nearly feel you may have an small manifold leak somewhere OR a dump pipe leak somewhere that's introducing additional air into your exhaust stream thus the lean reading.

Anyhow, easiest way to diagnose all this is on a dyno.

  • Like 1
On 8/8/2022 at 6:13 PM, Dose Pipe Sutututu said:

RBs are tough little things, to rule out any air leaks through the hot side, I suggest just take the car for a gentle drive and gentle load it up till close to 100kPA aka 0 psi for you Muricansssssss.

See if your AFR readings are somewhat richer than stoich.

I nearly feel you may have an small manifold leak somewhere OR a dump pipe leak somewhere that's introducing additional air into your exhaust stream thus the lean reading.

Anyhow, easiest way to diagnose all this is on a dyno.

I appreciate all your help and advice. I’ll finish tying up my loose ends, and get the car rolling around the neighborhood in the next few days and report back!

  • 2 months later...

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Similar Content

  • Latest Posts

    • For these last 7 years of ownership, I've always had to use a small scissor jack under one of the front tow hooks to raise the front just enough so my low-profile jack fits under to reach my subframe jack point. I'm beginning to get annoyed of always having to do this. Are there any lower low-profile jacks that fit under the gtr lip on a dropped car?
    • Seat of the pants assessment of the new intake: The car is way less "doughy" when hitting the loud pedal, especially off idle when stopped or in traffic, I did use a cheapo lazer thermal thingo to measure the temp around where the pod filter got its air, it was between 55 - 60°C, in saying this the car was shut off and not moving, so the OEM intake pipe was not supplying any fresh air to where the pod was when the car was at least moving A weird bonus was induction noise on the throttle in the cabin increased a bit,  I was worried that I was actually going to lose some of that induction noise I love so much, outside though, when I got the daughter to do a WOT drive by pass for me, the induction noise has increased alot when on the throttle, not quite ITB doort, but well up there I'm extremely happy with the results and have been exploring the country roads in the region  As for house mods: 1.New front fence is up and is awesome, it really upgraded how the joint looks from the street, and the added security is nice 2. Electricians have replace some interior lights, and with more lighting in the garage, a few new motion detecting lights out the front above the garage, front room, and at the front door, which I have already found heaps helpful coming and going, also now has fancy pants CCTV all round the house The only hold point for power though is the solar and batteries due to supply issues, although this will happen over the next few weeks 3. I have done a heap of landscaping out the front and I'm almost ready to do a new small retaining wall with some nice blocks to replace the brick and cemented in rocks around the raised garden beds cemented in river stone "was the fashion at the time" the house was built. I currently have a pallet of retaining wall blocks and 2 bulka bags of 20mm blue metal to replace the wood chip that is in the raised garden beds around the house 4. I now have 3 big raised garden beds for out the back to grow some vegetables, about 70cm high, 200cm long and 100cm wide 5. My 2 compost bins are already pretty full with brown, green and kitchen waste from the landscaping I'vedone so far, but they will probably take a few months to break down, so anything else that gets chopped, trimmed, and kitchen waste will just start filling the base of the raised garden beds to about 30cm before I start throwing 40cm of good compost, and stuff, for the vegetables to grow in, I'll need a few ton of compost and soil, but the local supplier can sent me bulka bags of the stuff Basically the logs, wood chips and a few strategically placed rocks for drainage, will give the beds some good organic materials down low to break down over time, and they will hold moisture during the warmer months to save the water in my big arse water tank if we don't get alot of rain So, all in all, the car and house mods are going well, and I'm really enjoying being retired, I sleep in too 0700 and slowly plod around inside until I feel like actually doing anything, and only work in the yard for as long as want, which has actually been alot over the last few weeks,  although when you look at it, it seems that not a huge amount of work has been done,  until I look at the before I started the work pics Happy days and good times indeed 
    • hahaha yeah. Plan is to get side skirts and probably just rear pods. But going to do them one-by-one. I've got a set that I really like from RHDJapen, but that one isn't shipped to AU. So need to find someone who can get it for me
    • Here's an idea, answer the questions I asked you as they are trying to work out WHY the LSD will be binding up in a straight line.
×
×
  • Create New...