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Hey everyone

Well i had a tune a while back on my car using an Safc/avcr and when i drive it and hit full boost it shows my boost hits 0.77 bar and goes all the way up to 0.90 bar, yesterday i was bored so just scrolled through the settings and noticed learn gear was on so i disabled it, as I’ve heard learn gear causes the boost to change a bit and doesn’t give constant boost? Secondly i went into my boost/duty cycle menu on my avcr and the boost was set on 0.75 bar, so i thought ill try put it to 0.8 bar.. then i took it for a drive, when i full boost it held at 0.8bar but when i hit about 5000rpm it went to 0.90 bar and it kind of sounded like it was hitting a fuel cut or some limp mode on the stock ecu so i stopped straight away.

i wound it back to 0.75 and again noticed it holds at 0.75-0.77 bar under 5000rpm then it reaches 0.88 bar above 5000rpm ( i set my avcr so it shows the highest number)..

Later on i was driving home and i had a query as i have a Apexi Safc 2 also. i noticed my fuel/air ratio on idle is at 5.8%, when i start spooling and hit boost under 5000rpm stays at approx 0.9% after 5000rpm or upper area of the rpm range it goes to 0.1%..

To help a bit more my car is a R32 gtst with the following:

Rb25det S2 engine conversion

Stock turbo

Stock ecu

Stock injectors

Straight through exhaust

Pod

R32 Gtr fuel pump

Apexi AVCR

Apexi SAFC

I just have a few questions first being is my car leaning out? Secondly if so could it be because of the R32 gtr pump or another issue?, does anyone know if having VCT can throw off the AVCR that much?

Thanks guys

Ni

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if you got your car tuned on a dyno it should be running good, first point of call i would consult the guy who tuned it.

secondly it sounds like u need to read into how to use the AVCR a little as i think you have your gain/duty set wrong to help you achieve target boost properly.

if you got your car tuned on a dyno it should be running good, first point of call i would consult the guy who tuned it.

secondly it sounds like u need to read into how to use the AVCR a little as i think you have your gain/duty set wrong to help you achieve target boost properly.

hey man, yer just downloaded the pdf for the AVCR now

quote

(it kind of sounded like it was hitting a fuel cut or some limp mode)

fuel cut is a big bang (some times) and a sudden loss of power

i doubt it was this

i think you would have been hearing abit of missing (pop pop pop)

if this is the case get your self some new spark plugs gap them to 0.8mm (or buy them pre-gaped)

wind you boost back up!

if it goes pop pop pop again, you have two options.

keep you boost low enough so it doesn't miss

OR

get your self some new coil packs

i use splitfire but there are a few brands most have been covered so do a search.

  • 2 weeks later...
quote

(it kind of sounded like it was hitting a fuel cut or some limp mode)

fuel cut is a big bang (some times) and a sudden loss of power

i doubt it was this

i think you would have been hearing abit of missing (pop pop pop)

if this is the case get your self some new spark plugs gap them to 0.8mm (or buy them pre-gaped)

wind you boost back up!

if it goes pop pop pop again, you have two options.

keep you boost low enough so it doesn't miss

OR

get your self some new coil packs

i use splitfire but there are a few brands most have been covered so do a search.

hey man, ah good to know it wasn’t a fuel cut then.. and yer i had changed my spark plugs recently so that wasn’t the problem either, however i found out it was my SAFC so all is good :)

hey i have the same problem with my car its a r32 gtst with the rb25det cant cant find out the problem. if u can help me thx.

hey man, for me it ended up being my SAFC that was set up wrong so i used my friends SAFC settings with the SAME mods as my car, and now the car runs great and it reads the proper way by the fuel/air ratio % actually increasing instead of the other way around..

Good luck man, Ni

Good luck man, Ni

Sounds like you need to adjust/reduce the duty a few % in the 5k rpm range

Because as you say the learn gear was on and it would have changed the boost map.

hey man

yep i turned of learn gear and put the duty down a bit, i think it was my SAFC that was the problem

i am useing a series 2 ecu on a series 1 engine u guys think that could be the problem? and my maf is the rb20det one form the old engine?

hey man

not to sure, but do you mean AFM? not maf? anyways that could be one problem, secondly try plugging in a S1 ecu, i dont see the point of having a s2 ecu if you dont have a Series 2 motor..

ok i will try 2 do all of those things. but this what the car dose it pulls out good but when i hit around the 5000 rpm's it its hiting a fuel or a boost cut i dont know what it is

and it missfires sometimes it sound like pop pop pop and the rpm drops too 0 and the car turns off some times.

ok i will try 2 do all of those things. but this what the car dose it pulls out good but when i hit around the 5000 rpm's it its hiting a fuel or a boost cut i dont know what it is

and it missfires sometimes it sound like pop pop pop and the rpm drops too 0 and the car turns off some times.

hey bro if you mean its hell loud pops and your car starts to jerk i had the same problem and mine was the crank angle sensor plug had a broken clip and had come of slightly and wasn’t making full connection

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