MicroSquirt.com read only forum (Jan.15,2018)

ford zetec 1800 with t3 turbo

ms v3,direct coil,std injectors,nb lambda sens

right got car started but rough idle.so eric gave me some advice of tuning ve table at low down revs to smooth out idle

First question dose my afr matter at low down revs??will i get proper reading??

at 900rpm my arf sits around 16.1,very lean,when i go to tuning,ve table,then move around green dot up(ritcher)my afr dose not move but car gets realy bad(ready to stall=to much fuel iwould think.


can any 1 help please, i would like to tru and get on the road for the weekend


thanks tommy

If you are changing the air fuel mixture and the car is reacting that much, yet the wideband (I assume) o2 is still reading the same old 16.1:1 reading then something is not right with your wideband, either the wiring of it or the sensor itself has gone bad. They can be damaged from leaded fuel, or silicone sealant (gasket goop) that's not o2 sensor safe being used upstream of the sensor, or just from being old.

You should definitely get a proper AFR reading at low revs if your wideband o2 sensor is working properly and is in it's proper temperature range. I'd look into this some more as it's a great tuning tool and will save you alot of time here.

One other thought--

What kind of wideband is it and how are you getting the reading? It's possible it's working fine but your display just isn't calibrated properly...

Also what ECU are you running, and what tuning software (versions).

xr3iturbo wrote:ford zetec 1800 with t3 turbo

ms v3,direct coil,std injectors,nb lambda sens

right got car started but rough idle.so eric gave me some advice of tuning ve table at low down revs to smooth out idle

First question dose my afr matter at low down revs??will i get proper reading??

at 900rpm my arf sits around 16.1,very lean,when i go to tuning,ve table,then move around green dot up(ritcher)my afr dose not move but car gets realy bad(ready to stall=to much fuel iwould think.


can any 1 help please, i would like to tru and get on the road for the weekend


thanks tommy

You say you have a NB sensor, and I'll assume this isn't a typo since N & W aren't close on the keyboard. If you have a NB, you can't know that you're running 16:1 -- the sensor isn't capable of that kind of information. You also didn't mention which version of MS you're running, so I'm assuming MS-I.

When I first got my car running, I was able to close in on 'usable' idle settings by using the EGO correction. Since you're running a 4 cylinder, you may want to change the 16 to 8, but 16 should work too. See the area outlined in red:



I've used these settings on my Chevelle, along with Jerry's little writeup, http://www.diyautotune.com/tech_article ... squirt.htm
to get my car roughed in.

*NOTE* -- do NOT go into boost -- this is for low load (ie-- idle, less than 60kpa) areas only.

-Dave

Dave's right, I missed the narrowband comment my first time through and with a narrowband sensor you'll have pretty much useless information EXCEPT when it's reading 14.7:1. Outside of that it will just tell you lean or rich, and somewhat erratically.

MStweak will help you tune it in with a narrowband-- if you want to fine tune things at higher loads and/or in boost you'll be best served by dyno time or with a wideband o2 setup where you can tune it yourself with accurate AFR feedback. Innovate LC-1 widebands are pretty affordable and do a great job with the MegaSquirt, and work great with MStweak too.

thanks guys,sorry for short hand,i am using a n/band sensor and my afr reading at idle is 16.1 so it looks like out to buy a wide band,i wont run car just now i will wait till get wide band

thanks alot for tour help guys