sj408

iTrader: (6)

Hey guys, so went through much headache after picking up a car from a local shop I had mystery misfires and liquid on my plugs, trans is slipping to all hell etc.

Now i got my plugs all cleaned out and its running smooth but before going into boost as soon as it went full boost it would peg to 10.5 and stay there. Now it looks like its around 11.5-12 which scared me so i haven't gotten into it hard at all.

cliff notes

-trans slipping to all hell
-plugs might be slightly fouled from misfires
-used to be 10.5 a/f in boost now 11.5-12 no pinging, but all it takes is once lol

95SC3T

iTrader: (3)

Swap out the auto junk and go manual.

The wetness on the plugs was probably excess fuel. 10.5 a/f is rich as hell. I'm not a professional but I believe all tuners tune cars to 11.5-12.5 anything higher than 12.5 is dangerous while in full boost. Take the car and have it retuned.

95SC3T

iTrader: (3)

Who told you 11.5 - 12 a/f is lean?

SC3NAT

Yeah I thought I heard that if your over like 13 a/f in boost its bad, not in the 11 or 12 range?

sikes

11-12 is lean for an "untuned" car, check fuel system to start with, just maybe the fuel pump is on its last leg.

95SC3T

iTrader: (3)

How is 11-12 lean? If the car is untuned it doesn't need to be driven anyways IMO. 11-12 is the target a/f that almost all tuners shoot for. Unless they are tuning on ethanol.

To the OP, just or your safety please don't drive the car if its untuned and get I tuned. I would really hate to read a thread about how the a/f was 11-12 and the car blew up. Just because a/f is fine, doesn't mean it's okay to drive. There are other things like timing that need to be looked at to make sure that the car isn't pulling timing and going to blow up.

95SC3T

iTrader: (3)

Op change plugs. If the others ever misfired I would change them. No use of chancing anything.

sj408

iTrader: (6)

OK? Soo since a w58 is not really an option, an for price sake neither is a v160. Sounds like i would stuck on an r154? which isnt the problem. Its the fact that i can just build an a340e for minimal cost, go high stall, upgraded vb and throw in a supra stick with my is300 steering wheel. And tbh, I still have not caught up with the same fascination of driving stick that everyone else has. I daily drive my car, seems like alotta work when you add in the clutch and arm action. I once drove 10k in a couple months in my old sc. cant imagine shifting.

Car is not currently tuned. Have 14kish miles on it so far with an aristo ecu and a/f has always been consistent 10.5 in boost. Since i was not looking to use aftermarket tuning for a while its fine though im sure leaving gobs of power on the table.


Im speaking relatively before and after issues/changes. I had consistent 10.5s in boost before with the aristo ecu as others do.
Fuel pump is brand new, Injectors were said to be though bought second hand so who knows.

Its been driving great for 14kish miles now of daily driving. This is a new issue im seeing, likely will check timing. Change plugs and go from there. I run 8 degrees of timing base with the aristo ecu also retarding timing on shifts. Car is pretty basic setup-wise and very conservative.

Thanks for the advice guys, ill have to start with basics, ill let you know what i can find.

lexforlife

iTrader: (7)

a/f of 10.5 is not good either .. you are washing down cyl walls with fuel and diluting your oil . not good for oil on bearings .. target should be around 11.5 ish and as pump hp goes up closer to 600 then you want to richen it up just abit at peak trq . toyota pistons love to run and the richer side but once you delve into the mid to low 10 range , you are diluting your oil .. if your tuner is tuning you into the 10.s which is robbing power as well , then hes making up for some loss by adding timing , not a good approach

sj408

iTrader: (6)

Thanks for the info, i do plan on aftermarket tuning soon. Its not a good approach to respond fully without reading through the thread fully. Im on a stock aristo gte ecu, there is no "tuner" per se.

For everyone, Took a ride today with my buddy and it seems to be back to normal. but boosting high than expected from my 10psi spring.

lexforlife

iTrader: (7)

i did read the thread , just letting you know that seeking to run so rich is not a good thing ..

sj408

iTrader: (6)

Oh ok? was wondering who you were referring to when you spoke of my tuner "tuning me into 10.s" and "he's making up for the loss by adding timing " Im on a stock ecu there is no "tuner" like i said before.

I appreciate the response though.

Ali SC3

iTrader: (10)

yeah its just the tendency of the aristo ecu to run that rich, maybe the US spec runs a little better cause of emissions requirements being very different. I change my oil out pretty regularly it does tend to get darker a bit quicker but I haven't noticed any issues either.
mine does the same thing except it pegs at 10.0 at 14 psi. most people solve this by installing a bcc and turning up the boost till its in the 11's. if you are na-t make sure you at least have a tt headgasket to run more boost.

It's possible one of the plugs was fouled for 14k, but more likely there is something different now, I would change the plugs anyways bkr7eix is my go to plug. how you route your charcoal canister can affect afr's because of buildup in the tank starves the pump so double check on that, and also the line on your fuel pressure regulator I wouldn't tee anything off of it except for maybe the map sensor so whatever the map see's the regulator see's and everyone including the ecu are on the same page.