I had a jza70 ecu with my soarer harness, and I just installed a 2jz gforce ecu on my car. Now my car is running really rich, it seems to be breaking up a lil bit if I cruise in the 1500-2500rpm range, & my car idles between 1000rpm & 600rpm, which is lower than before.

My main issue is that i'm going single (precision 6266) very soon and would like to get feedback so I know what to do next....


Only mods to the car/motor are: gforce ecu, boost controller, & fmic.

How do I fix the running rich issue? Since the ecu is from a supra, would I need at least 550cc injectors & a tune?

What is causing the car to break up if I cruise at 1500-2500rpm?

I have an apexi SAFCII, but was told to sell it and get an AEM FIC...thoughts? Only ask because I see a lot of ppl using the SAFC, but will the AEM be better since I'm going single?

Will a fuel pressure regulator help at all?


Any other suggestions/Info?

Thanks

 

what injectors are you running? those GeForce ecu's are modified for a specific car and setup. you'll probably have to have a piggyback to get it dialed in .

 

I am on stock 370's and should I use the safc or an aem f/ic?

 

you can use either one, the safc is simpler and has less options, the fi/c is more complicated wiring and tuning but has much much more options. both should work on your car.

is it from a USDM or JDM supra. and do you know what injector size the G force is mapped for?
You will need to figure that out. you shouldn't be running rich, if it was mapped for 550's or larger and you are running 370's you would still be running lean even though there is the difference in displacement.
If its mapped for 440's I would think it should be very close as it is. If its mapped for 550's or 660's I would imagine you need larger injectors and you are running lean right now.

I can't think of a situation where your 370'cc injectors are running rich from an ecu which is programmed for larger injectors even with a little less displacement. I remember reading a few threads on using a 2j ecu on a 1j ecu, and they had figured out the injector sizes needed on a 1j for the different 2J ecu's. You need to know what your ecu is programmed for though or it will be a guess and check.
If you have a wideband you would know right away and it would be easier to tune.

 

the gforce ecu's are USDM ecu's IIRC.

which means it should be mapped for 550cc or bigger. Like Ali said you should be running lean with your current setup

I personally wouldnt bother with an safc, your going to need something more capable once you start going single and addding cams etc

first thing you need to do though is get a wideband and see what your AFR's are doing.

Look into the mapecu, emanage, and the aem fic

I personally have the emanage and i like it a lot. Its not perfect but it gets the job done. A majority of people use the mapecu and have good results . The aem is newer(atleast in the jz world) and less people have used it, but i think a few people have had good results

you might want to try and find a stock aristo ecu and a set of 440cc's, itll be a lot better tune for what you have now. Ive personally run the aristo ecu w/440's and had excellent drive-ability on my 1j

 

Exhaust tips have smoke, smells like gas, pops during deceleration, bumper turning black, etc...is that rich or lean?

instead of buying the mapecu, emanage, & aem fic, why not just go full standalone?

Instead of wasting time/money buying stock ecu's & 440's, should I just go with a full standalone, bigger injectors, etc. since I'm going single soon?

I want to avoid buying parts, then having to sell them to get better parts.

 

it really depends the whole standalone vs stock ecu thing, and what you will be happy with.
stock ecu may not have the best WOT tune, but regular driving is going to be good.
standalone is usually the opposite, you will get max potential out of your setup, but regular drivability and starting won't be as good as factory without a lot of tune time. Remember its not only the cost of the standalone, be sure to factor in the initial tuning, and you may want to have some things tweaked or re-tuned down the line.

 

this^!! if you have the time, money, and a compitent tuner a good standalone is the way to go

 

Do you have a wideband? That is the first thing you should do.

When I ran the Gforce ECU I used it with the HKS VPC W/440 chip and Safc. RC 440 injectors and a walbro. My tuner did not like its stability and obviously standalone is much better/safer especially if you have a good tuner like Ian, but if money is an issue you do what you got to do.

 

i just switched to a jdm 2j ecu with 440's on my 1j and have been having the same problems. on a 3rd gear wot pull it would hag till a certain rpm and then take off. my buddy that owns kaizen motorsports in socal said it might have something to do with the o2 sensor. ill let you kno if it fixes anything when i change mine out

 

didn't know the 2j and 1j had the same ecu plug pins.

 

Im using a patch harness

 

I'm getting 550's & aem wideband now....should I go with a mapecu or the aem f/ic?

 

if you get the injectors that the ecu is programmed for you don't need either of those.
The wideband is good to have for monitoring, but the gte ecu will only connect up to a regular heated o2 sensor.