Spec S converted with SR, my old HDev 3a set up from my 14a.
No matter what I do I can’t seem to cure it leaning out.
It overfuels massively off boost (boost leak I’m positive and quite possibly goosed lambda) and then on boost runs lean (circa 12.5-13 AFR’s)
Literally have had enough, I really need someone (or suggestions of who to use) to get it sorted
The alternative is to get rid of it. not something I want to do but I’m getting absolutely sick of it.
Thank you
Gary at APT?
Fuel pressure ok?
Right injectors for map?
Originally Posted by sideways14a
Fuel pressure at idle is 3 bar
everything that was in my 14a which ran 3a for years is in this car..
I did replaced the Z32 as I tried Another forum members spare one and the AFR was spot on which lead me to believe mine was buggered, but my new one didn’t sort it out.
In another thread yesterday I did try another very high flow rate fuel pump which did altr the fuel pressure and made no difference to AFR, this pump has since been removed and the original 255 put back in.
Just to add and illustrate how lean it’s going, my avcr is turned to off so it’s on actuator pressure of 0.8bar and still has high AFR’s
Last edited by Hugh Janus; 08-04-2018 at 03:12.
Ah yeah, might give him a call next week. Tbh I didn’t think he really got too involved with SX’s these days.
Is that 3 bar with the small/thin FPR vacuum line removed?
No, thats 3 bar with pipe connected and it was always like this even on my old car too.
Redo the grounds on the maf
Good call actually
Edit: actually I had cut back the earth back to the loom (pigtail) and replaced the earth as I noticed the wire had surface rust, however the pigtail and plug haven’t been touched
And there is only 1 earth? It was orininally on an exposed thread on the inner wing it’s now earthed to a bracket above the expansion bottle, the paint has been removed earth bolted up.
Last edited by Hugh Janus; 08-04-2018 at 10:06.
If you need my Z32 AFM again then no probs, just say.
I've been "just about" to go Stage 3 for the last five years now (reminds me, I still need to collect the Stage 3 Horsham chip I paid for over two years ago)
So pretty safe to say I'm not going to miss it if I lend it to you again, this time for an extended period if it will help. I did offer to leave it with you last June when we met up at Johnny's to do the test swap if you recall - should have taken me up on it !.
Don't give up, too few cars around as nice
PS. Also got the original pigtail + an ebay pigtail spare if you need a tail and plug for swap / elimination purposes.
Then maybe I can twist your arm for a hand fitting one of them to my own loom if I ever do get around to making the jump to Stage 3....? Though don't hold your breath waiting for that day to come - I'm still on the "if it ain't broke don't fix it" stage !
Cheers
Last edited by Rochester; 08-04-2018 at 11:36. Reason: Grammer and speeling
It's likely this is your problem.
3 bar is your base fuel pressure (as per FSM), at idle engine vacuum should pull the fuel pressure down to about 2.5 bar, if it stays at 3 bar then idle will be rich
On boost fuel pressure should be 3 bar + whatever your boosting, if it stays at 3 bar then potentially dangerously lean
Replace the vacuum line to FPR and go from there
If it fixes the problem or not, it's worth extending your FPR gauge, clip onto wipers or bonnet then see if pressure follows 3bar+boost
I replaced mine for no real reason, when I removed it the vacuum line had gone brittle on the ends and tore off the intake mani.
Last edited by immy21; 08-04-2018 at 12:55.
Hi Dude I literally couldn’t remember your name, but thank you for your offer.
Thing is ended up buying a brand new Z32 from Nissan shortly after trying yours as it really did make a differences the time but ultimately didn’t, so Im just about to order a new pigtail and completely redo the loom is where I’ll go next.
Again thank you though, club spirit
Z32 MAF has 2 earths. One is ECU ground (all MAFS have ECU ground) which should be connected to the original MAF wiring, the other is chassis ground.
Normally MAF's have V+, signal, ECU ground. Z32 has a 4th wire which is chassis ground EDIT: 4th wire not to be used
To confirm which 3 wires on stock loom are which
1. check which one is V+ with a multi meter
2. then do a continuity test (google it) between TPS plug/wiring and MAF wiring, 2 wires will have continuity. You already know which is V+, the other will be chassis ground, the 3rd and only other wire will be signal, now you know which wire is which.
To confirm what each pin on the Z32 is, just google, tons of pics. It's important MAF's ECU ground is connected to the loom and not to the chassis.
EDIT: It's been a while since I'v had a Z32 MAF
Have a look at this Nistune PDF, like I said Z32 (D) ECU/Shielded ground to wiring loom but instructions say specifically NOT to connect other ground to Chassis
http://nistune.com/docs/MAF_and_Consult_pinouts.pdf
Last edited by immy21; 08-04-2018 at 13:04.
Mark, I have a brand new in the bag Tomei pigtail for a Z32. You can pop round to collect today if you like.
if you have a FPR gauge then I would do as immy says and see what its doing under load.
just jack the back wheels off the ground and load it momentarily using the handbrake whilst watching the gauge.
Can I pop over this afternoon will be much later though, what’s your number?
PMed.
Are you sure your AFR gauge and sensor is accurate? Have you compared it against a RR run?
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