Hi all,

for those who heard before my problem. i'm running a remapped ECU that's boosting at 0.9 BAR STOCK TWINS.... but at the peak of the boost level, my air fuel still remain at 7.9 to 8.5 range...

i don't think stock injectors are capable of pumping that much fuel at 0.9 bar setting. suspecting the injectors are non-standard 550 850. i have no history on the car.

my question will be, how do i check if the injectors are still stock 550 and 850 or changed to something like 550 1000 ?

 

You have to pull the injectors and have them flow balanced by an injector shop.

 

Mahjik knows the dance.

And 7.9 AFR? Wow...be careful!

 

Are you using a narrowband o2 setup, or a wideband? If it's a narrowband, don't pay much attention to the reading.

Either:

1) Your AF data is incorrect due to having a narrowband.

or

2) Your injectors (upgraded or not) are running a really high duty cycle which could be quite dangerous.

I think it's probably #1. 7.9 to 8.5 is so rich at WOT the car would not perform well at all... If you really do have a wideband set up properly, pull the injectors, and either have them flow tested (always a good idea anyways) or post some pictures of them. I know there are some people here who could tell you what they were just from looking at em.

Good luck!

 

I've never seen a wideband measure below 9:1, most don't go below 10:1, so how are you getting your results?

 

the numbers i obtained from a dynotune shop....their AFR meter able to read 6 onwards. no idea if it's a narrowband or wideband.

as for injector balance and inspection, i need to source for a injector shop that does that. not sure if in my country they have anyone that able to do that.

now i started to be worried.....

i need sometime to get it done.....




a remapped ECU can cause me such problem... sighs.... terrible terrible...

 

I'd love to know what they are using because I've never seen a professional wideband that went below 9 or 10:1, as I stated above. I also find it hard to believe the car would run really great with those AFRs.

Anyway, I would be surprised if your country doesn't have any injection engineering services, but if not, you could send to RC Engineering in the USA for cleaning/inspection. Otherwise, you could just pick up some new injectors if yours are in bad shape.

 

actually, the place i get the reading below 9 is from this place called Links Dynotune.
pretty famous shop around in my country. famous for tuning Lotus Elise, Subaru Imprezzas and Skyline GTRs. previously i tried at other place that uses Dynojet. their afr reading flatlined at 9 from 5000 RPM onwards.

after all the boost fix etc here and there..... i haven't got the chance to put my stock ECU on it to run on the dyno. i've only done it on the remapped ECU.

about early this year, i got my injector full serviced.. took out by mechanic and sent for full cleaning. but i'm not sure if my country have the services like injector balancing or pattern analysis.

ditch the remapped ECU go for PFC ? or continue to diagnose my injectors ?


stock ECU runs on the road without any staggering at all. but having quite a big spike 0.8 BAR before internal wastegate regulate to 0.6 BAR. not as responsive as the remapped ECU that runs solid at 0.9 BAR drop 0.1 BAR during transition and then stay solid at 0.9BAR.

if u ask the question hard to believe it runs great on those AFR.... yes.. it runs better than the stock ECU but not good when it's at 7K RPM... staggering happens...

 

hi nan777,

of course we have the technology in Malaysia to flow test as well as spray callib. test. Call GT auto and talk to thomas. Tell him dave sent you.

I doubt you're running that rich.The car would run really badly. What wideband did they use? Where did they get reading from?

 

When was the last time you changed your spark plugs and wires?

 

If a place was set up to tune with E85 ethanol blend or 100% ethanol then their sensors would be able to read down to ratios of below 7:1. Not too sure if you can use these sensors with gasoline though?? Under 10 is just too pig rich.

 

dave,
i got those readings from Links auto. near GT auto.
i got those injector sent for cleaning by ah choi but did not have any report regarding the flow rate etc.

goodfellafd3s,

my spark plugs i routinely take them out to clean and put it back. i have 2 set, 1 set NGK 8 and 9. another set all 10 iridiums. i rotate them once in awhile as long as they are not fouled.
my plug cables i just changed to Apexi power cable plug like beginning of the year.

shall i continue to debug the injectors or focus on the ECU ?

 

injectors or ECU ?

stock ECU runs fine. but never dyno them before. earlier with alot of leaks. my stock ecu giving me lowest af at 12. this remapped gives me 8

 

the other question will be is it possible to have stock ECU to provide that MUCH fuel........