LSEGHATCH

So one day while driving the sc, it quickly bogged for a sec and then continued to normal. No more than 3 minutes later it bogged and didn't come back and the A/F's read low 10's/RICH.

Well it hadn't done that up until a week ago when out of nowhere it bogged so I pulled over, waited, and continued on my way. Later that night, after being parked for hour+, I went to leave and it wouldn't even idle and it still doesn't. A/F's read 10's/RICH so I'm thinking that my injectors are sticking/stuck open.

Now am I experiencing dirty injectors or shot injectors? From what I've read, 550's should be able to handle the mid 400hp numbers the car is putting out. My main question is should I pull the old and have them tested/cleaned or should I just go and pick up some 6XXcc's?

Also what style injectors do these cars run?

craaaazzy

iTrader: (4)

first question is: what are you using for tuning? if ur rich w/ the 550's, u'll be even richer w/ larger injectors.

LSEGHATCH

I am using SAFCII to tune as well as a PLX for a/f reading. I know where your coming from but I am running rich between idle-2k, which is all it will let me rev to when it does this.

I was thinking more along the lines of them being high in thier duty cycle while in boost, A/F's are fine, therefor being worn out. None the less I'm thinking I'll have them cleaned, tested, new fuel filter and then see where that takes me. Would be much less than 4XX for new injectors.

morris

iTrader: (2)

I would try resetting the ECU and see what happens, it may be that you fuel trims have gotten out of wack.

This happens to me on my SAFC setup

LSEGHATCH

How exactly does one reset an ecu?

morris

iTrader: (2)

Sorry disconnect the negative battery terminal for a few hours, I ussually do it overnight. But I would say 4 hours to be sure.

With the SAFC over time the cars computer starts to fight the SAFC's adjustments, ussually resulting in eratic AF's resetting the ecu eliminates what it has learned. The best way I have found with teh SAFC to minimize this effect is to make sure that the car is dialed in around 14.7-15 for regular driving around town rpms

LSEGHATCH

I totally didn't think of this and have heard about ECU's overpowering the SAFC units. Thanks, for some reason I always find the most expencive cause for the problem and get hung up on that being the cause.

LSEGHATCH

Well I disconnected the battery and it ran good for most of the day. Let it sit for a while and it acted up while I was driving about 3 miles away. Disconnected the battery, let it sit for 10 min, and it made the rest of the trip to my destination and back without a hickup.

It acted up about 1 mile after I got on it good which means I was rich for while. If there any way around this? I'm 11.5-12.5 while in boost/on it.

5spdSC300

iTrader: (1)

Do you have any afc adjustments in close loop? If you do it sounds like the ecu is fighting the changes. A common thing for MKIV supra turbo owners that run safc's is not to make any changes in closed loop and only use the afc for WOT open loop tuning since the ecu will always readjust any changes made. This has been my experience with the 2JZGTE motor.

SCoupe

You might benifit from an hour on a dyno in the hands of someone who knows 2j's, it might better point you to suspect areas than cleaning or buying new injectors. Pulling injectors is a hassle. They are a PITA to get to.

Just in case, one of the best injector cleaners out there: http://witchhunter.com/

LSEGHATCH

When you say closed loop do you mean "Low" on SAFC? If so, there are adjustments made in that category. I've tried to mess with them but it runs really rough, is there a way I can earase that and only that section on the SAFC so that it runs straight off the ecu until full throttle?

morris

iTrader: (2)

The way to do what you are asking is to set the low settings at zero anjd then adjust the thottle point to whrere you want it for open loop ops, which would be less than full throttle I wouylod think.

I also kont know if I would reccomend doing this but I guess it is woreth a try. My guess though is tha tyou will be way to rich if you zero out your low settings. do you have a wideband so that you can see the effect of your tuning?

LSEGHATCH

Yeah, PLX M300

ranger2339

Your injector drivers on the ecu might be going bad. It happened to me when I had a 1j in my mkiii and a few others..I would also disconnect the safc and put in the stock inj. and see if you still have the same issue.also take the cover off your ecu and look for any brownish spots on the pc board,that means its burnt and on its way out.

Josh

LSEGHATCH

I'll check the ecu, I don't have stock injectors to throw in.