Ozmi007

hi guys,
i recently put in new injectors and im sure i have not adjusted something and i have missed a step but on idle and cruise everything is fine in regards to afr however on 1st start up cold it is lean untill a little while then settles normal any help

CDrinkH2O

iTrader: (7)

We need a little more information to help you.
What injectors did you have before and what did you change to?
What fuel are you running?

Ozmi007

Sorry cdrinkh2o it was very vague description let me try again


I have an evo 7 with a telphra 9055701 rom I had standard injectors


I recently purchased id 725cc running 98ron only, now I did get values when I purchased the injectors for latency however the volts are not the same as ecuflash, it idles ok, my oxygen feedback trim is at like 20% but on cruise not bad, its all good on warm start up idles fine at 14.7 but on cold start up its lean to 17.6 until it gets a little warmer im guessing but all I did was change scaling and latency so I doubt I would need to adjust anything else apart from them, now I have looked at all the info but cannot make much sense of it all.

CDrinkH2O

iTrader: (7)

Try these settings as a starting point for your latencies:

Voltage ms
4.69 4.512
7.03 2.352
9.38 1.512
11.72 1.080
14.06 0.792
16.41 0.648
18.68 0.552

Try 715 cc/min for your injector scaling.

This information is from the manufacturers data sheet attached. I have interpolated the latency values to match the ECUFlash voltages.

Next, go read Merlins Tuning Guide section 5 starting on Pg. 66. This will tell you how to dial your injectors in.

Ozmi007

thanx cdrinkh2o im going to give it a go now and let you know what happens

Ozmi007

hi cdrinkh2o,

i gave it a go, it started great now in the morning the only thing is that my stft is still at like 15% and thats with the injecotrs scalled down to 573 and my ltft is 12.5%

CDrinkH2O

iTrader: (7)

It is time to read Merlin's guide before you go further. Once you have read it come back and tell me what you think your next step will be. I am happy to guide you in the right direction.

Ozmi007

Hi cdrinkh2o

ok, so ive read it like 100 times and this is what i have, it idles great now and not lean.

However, my STFT is almost ZERO with is great, my LTFT low is at 12.5% my LTFT Mid is atr 8.2%
now this is with injector scalling down to about 533 and latency just a little bigger then standard.

According to Merlin's guide i would need to lower the scaling down as they are both a positive reading but what my concern is that im already lower then the standard scaling and i do not know how low i need need to go before it affect everything.

CDrinkH2O

iTrader: (7)

It's a balance between adjusting latency values and injector scaling. If you had to go down to 573 cc/min, then they are either not 725's, or they need cleaning badly.

Start with adjustments to latency. Your LTFT low is telling you to increase latencies by 12.5% across all voltages. Do this first, warm it up, and idle for 16 minutes. This should bring your LTFT low down to close to zero. Rinse and repeat until you are within +/- 5%.

Next go and drive it at a steady throttle for 16 minutes and then check your LTFT mid. If it is still at +8%, then reduce your injector scaling by another 8%. Rinse and repeat until you are within +/-5% .

ReidFletcher

iTrader: (1)

Sounds like they aren't 725cc injectors.

Did you buy new or used is the biggest question. If they are used, remove them immediately and have them cleaned. Ask the injector shop what size the injectors are. If they are new, start asking questions. ahah

RightSaid fred

Fuel pressure?

superkizuna

iTrader: (2)

I don't understand how your STFT can be close to zero but your LTFT Low and Mid is so high. I just installed a new Walbro 255 and a set of PTE 780cc injectors in my Evo 9 like last week. I just finished the MAF Scaling and now I'm cruising close to zero on all trims. I also used the mighty merlin guide but I had some help from the forum members as well (thank you guys).

Are you on a stock fuel pump? If so that is your problem but if you have an upgraded pump then the issue is something else entirely.

Scaling 725cc injectors down to the 5 hundreds is not the way to go. I understand that you are following the guide and attempting to lower the latencies to add fuel to the AFR at cruise but that scaling is very low.... like stock low. I don't think this is an FPR issue but I could be wrong.

I got good numbers from scaling my injectors to 696 (as per Merlin's guide) and adjusting latencies until I got them as close as I could to zero. Then, lastly, MAF Scaling brought me to around +/- 2 on trims. I also only have 264/264 sized cams; not sure what you are running but cams play a big part in idle.