wideband readings

[mattysr20]

Ok I've searched but can't find the answer .I'm just frustrated and wanna figure this out cause the shop can't get me in till next week some time......

so anyways for starters
95 240 ax
s15 Sr20det
normal mods
turbo mani
Megan down pipe
3" cat back exhaust
stainless lines
Megan fpr
circuit sport grounding kit
turboxs bov
turboxs mbc
autometer wideband
HD fmic
Jim wolf tuned ecu
444 injectors
z32 maf
walbro inline fuel pump
12 gallon fuel cell in trunk

ok my issue is my wideband gives crazy reading all the time.
when its cold or cool out it stays at 14.7-15.0 sometimes going a little rich if I get into boost . but when its hot out it goes crazy even when not boosting at all it jumps from 15.0-10.0 and back up to 15.0-14.7 then jump around in between.
I've tried a few things but nothing helps at wot sometimes its rich and other times its lean so I can never tell what my exact reading is.
I do know my bov was leaking and might still be even though I put washers in also I'm pretty sure my fuel pump is going out cause it been acting and sounding funny lately. Is their something I could try? its driving me nut cause I don't want my car to be F-ed up.... I have a video of the wideband reading while driving I just don't know how to post it but I could email if someone wants to see it..

[mattysr20]

Help

[Hijacker]

Gotta be a bit more patient than 2 hours before you start bumping your thread.

As for your issue, I'm trying to figure why you got a tuned ECU but retained factory injectors. At that point, it would have been better to have stuck with a stock MAF and ECU.

Call Jim Wolf tomorrow and relay the problem to them. One of their support guys can probably give you a better walkthrough as to why the car is acting the way it is. You can do a few things to test some stuff on your own. Take a multimeter and make sure your MAF is behaving properly at idle and at 2,000 RPMs. The service manual can be found at http://www.nicoclub.com/FSM get the EC section from the 300ZX folder, skip to the trouble diagnosis section and look for the page that the MAF trouble shooting section is on. It will give you the proper voltages.

Also, you're running an adjustable FPR, but do you know what your pressure setting is?

Double check all your grounds are properly secured and in the case of the MAF, the extra ground was tied in properly to the grounding system. Double check all the vacuum lines are hooked up properly. Lastly, call up JWT and make sure that it's not an issue with the tune. As much as I like Jim Wolf, I've gotten a wonky tune before on a customer car.

[mattysr20]

My fp is 40 psi and my boost is on stock sorry for bump I was editing my thread and kept messing up as I'm using my phone and its a pain in the a**

[IanS]

Have you checked the ecu for codes? You may have a knock sensor on the fritz, or the MAFS.

It's also possible that the gauge is reading improperly. Does the car seem to bog or feel odd when its acting up What brand sensor and UEGO controller are you using. How many miles on them, and where is your sensor located?

[mattysr20]

Like for instance on my way to work it was 70 outside and it was going crazy while driving normal and out of boost now on my way home its 58 and the readings are perfect driving the same ? Doesn't make sence to me

[mattysr20]

It's a autometer gauge and its on the top of the downpipe like 3-4 inches from turbo and its a couple years old how to I check for codes? Can I use scanner since its a 95?

[mattysr20]

Also it drives awesome all the time no bogging no dying no bad idle nothing and pulls like a champ.

[mattblancarte]

The sensor might be malfunctioning. If it's only 3-4 inches from the turbo, it may be overheating. Most wideband sensors I've seen are installed at the bottom of the downpipe, or even a few inches further downstream.

You may want to play it safe and stay out of boost until you are sure of what the problem is.

[IanS]

The car is a 95, but the engine and ecu are not. Besides, nobody ever wires up the consult port anyway, and only some of the 95s had it.

I don't know the procedure for the s15 srs, but the s13s have a potentiometer switch on the side of the ecu. Check the fsm for the exact procedure.

Most UEGO installation guides will tell you Togo a little further from the turbo for instal to prevent you from cooking the sensor. That being said, I ran my AEM in that location for years without issue. I have been running my Autometer in the down pipe of the rally car for a couple years, and as of my last event, it's been acting vey strange, and I think it may be dieing.

[mattysr20]

Ok correction the o2 for the wideband is at the bottom right at the bend kinda at an angle I was looking at the other o2

[mattysr20]

Ok correction the o2 for the wideband is at the bottom right at the bend kinda at an angle I was looking at the other o2

[mattblancarte]

Try replacing the sensor and see if that fixes it. Or, take it to any shop with a dyno and they will be able to give you an accurate AFR readout.

[mattysr20]

my fp is 43 not 40 should i turn it down ?

[mattblancarte]

Nah, that sounds about perfect. Unless you are spitting black clouds of smoke out of your exhaust pipe, that is.

Really does sound like a sensor gone bad, or maybe a wiring issue with the afr gauge. Start with the most common issue, which is the sensor failing.

If you are occasionally getting good readings, but then it tweaks out, it sounds like a bad sensor. Especially considering the engine has been running really solidly and doesn't seem to be affected by the bad readouts.

[mattysr20]

ok cool yea no black smoke and no bad running