turboed350z

Ok so my car has been running fine for awhile, and now out of no where, when i go into boost, the boost gauge still reads 7psi, but the afr is at 10.1.

Feels like a power lose or its also possible im really use to the power. Anyways, is this sign of a boost leak?

Any input?

bealljk

iTrader: (13)

I apologize that I don't know your build but what are you tuning with? whats your method of FI? (feel free to link me to your build)

If your normal Mani Abs Pressure is 7psi what make you think you have a leak - just your rich AFR? If you feel power lose due to a rich condition I would start looking at what is controlling your fuel.

Because it just started I would look into mechanical aspects of your build such as your waste gates or vacuum lines.

Do you have the ability to check your compensation tables to verify that a (IAT, CTS, MAF) sensor didnt go out keeping your tuning map in a rich zone?

turboed350z

Ok so i have no idea whats going on, but i did 3 pulls and the afr seems to be perfect. 11.1 at full boost and the car pulls hard. I guess i will have to keep an eye on things.

turboed350z

So last few weeks my car has been dipping into low AFR again.

I noticed that it happens on hot days. Is this possible? Can i be running rich due to outside temp being 90-100?

Hotter air is less dense, so same amount of air flow, 7psi, but less air molecules causing it to be running rich?

Unicus

iTrader: (3)

Hotter air, less oxygen. Same as if you go high alt. What's the humidity like there?

turboed350z

No humidity. Just extremely hot and dry

rcdash

iTrader: (18)

lol. Answer the 2nd post questions! We have no idea when you post no data. At the moment my answer is "something else".

turboed350z

in the third post i stated that everything went back to normal. now, a year later, it happened again. around the same time as it usually gets hot this time of year. and since i dont daily the car let alone get on it much, i only notice this problem poping up this time of year.

but to answer the question in post 2, i am tuned with uprev. the problem did suddenly happens and it comes and goes. which leads me to believe it isnt a sensor related. i havent had this problem in the colder days which lead me to the follow up question.

the car was tune in jan when temp are at the coolest, with temp rising over 40F, is it possible for the heat to be the reason for the AFR to dip into the 10s from 11.4ish? i recall remembering something about tuning cars in the fall or spring since that when the temp is roughly in the middle of too cold and too hot which helps during the winter and summer months from keep a steady afr. not sure if its true.

my thinking is, since the pressure is still the same, hotter air has less oxygen molecules there for, for the same amount of psi, im getting less air, causing the rich condition. im no pro, thats why i am asking you guys. just trying to give you my train of thoughts.

edit: i switched out MAF and cleaned my TB, and problem still pops up every once in a blue moon.

rcdash

iTrader: (18)

If tuned with UpRev the MAF accounts for air density with the built in temperature sensor vs air flow. You need to data log your MAF readings, AFR, and air temp during a run when the issue arises. It sounds like you may have a cell in your map that is off. It probably just did not come up during tuning as that load or temp cell was never hit.

turboed350z

So i should try to to find a way to data log it and get a retune?

Yesterday temp was around 75ish, took it out and the afr seems fine. But in the high 80s near 90s or higher, it starts acting up.

rcdash

iTrader: (18)

I have not used UpRev in a long time. Can you check for an air temp compensation table? Post up your screenshots for your maps if you have them. I suspect a software (tuning) issue, but logging is the best way to confirm that.

turboed350z

Im going to have to find a wat to data log it. Because as of right now, i have no way to log it

BoostedGSdn

Funny im having the exact same problem. Momentum ST kit. Long x country drive last hour it threw a code P0172 System too rich bank 1. It idled a bit shittier with a very noticeable power loss 10:1 under boost. Also normally it hits 8psi easy, now it hits more around 6-7PSI.

Also a weird thing the BOV sounded very weak and airy sounding and it didnt flutter like it used to during low rpm shifting.

I pulled out and cleaned the maf (Uprev) and thought I would order 2 NTK AFR/o2 sensors. Installed and cleared the code took it out for a drive same problem.

10:1 under boost very weak sounding BOV power loss. All I had time for was to do a cigar boost leak test and found that the boost gauge filter was cracked and leaking so i pulled that out I didnt have time to do a serious boost leak check because I had to park the car and go back to work for 2 months so Im sitting here wondering what it could be. Im assuming boost leak so when I get home Im gonna hook up the boost leak tester and soap that thing down hopefully thats it.

If you fix yours post it up!

turboed350z

My initial thought was boost leak also, however, the more i drive the car, the weirder it gets.

Everything, fuel, boost, power all seems to be in tact. The only difference is that my AFR gauge is reading weird. Itll read 11.2 one day, then 10.2 the next. And im pretty positive that it ISNT the gauge itself since i had JUST replace the sensor and gauge not too long ago.

Havent driven it a while since it now has a seperate issue, but ill end up making a thread for that later on today.