The Top DSM Community on the Web

For 1990-1999 Mitsubishi Eclipse, Eagle Talon, Plymouth Laser, and Galant VR-4 Owners. Log in to remove most ads.

Please Support Fuel Injector Clinic
Please Support Morrison Fabrication

o2 not cycling (log inside)

This site may earn a commission from merchant
affiliate links, including eBay, Amazon, and others.

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

dynedta

10+ Year Contributor
33
0
May 10, 2010
Massillon, Ohio
heres my log, o2 isnt cycling (brand new) also it seems like everything is really rough, any ideas???

agggh I should add im using 3"gm maf with ecm cable blow through, evo 560s, 43psi base fp
 
Last edited by a moderator:
Cant look at it right now as im at work but you can get a bad o2 sensor even if you just purchased it so get a multimeter and get testing it.
 
Ecmlink forums have the evo 560's listed as a -18% compensation, you are up at 25.4%.

Try changing that and see if it corrects it enough to cycle your 02.
 
Something strange is definitely going on.

It looks like your O2 signal is intermittent (maybe a wiring issue?). Pull another log and include your battery voltage, ICS, and idle switch.

Have you adjusted your TPS? Your idle seems to be high and not very stable as well.

Global fuel is close at -25, but you have deadtime set to 0. I have no idea what the DT for Evo 560's should be, but I'm pretty sure it isn't 0. :)

With the GM MAF in blow-through, you almost certainly have airflow issues at idle, but you haven't done any compensation for it yet.



EDIT: In that log, you have the ECU locked in BISS adjustment mode.
 
ok heading out in a second to do another log with revisons, i have done the tps adjustment (via dsmlink vid), yea global settings should 18% like artic said with dt set at 0, hopefully after i get this o2 thing figured out it will help the maf situation
 
Last edited by a moderator:
yea global settings should 18% like artic said with dt set at 0

Where are you getting 18% for fuel?

Using the calculator in link, I come up with -25.5% for global if you are running 43 psi base fuel pressure (although I'm not sure why you aren't at 37psi). And why would deadtime be 0? Although it's possible to have DT at 0 (depending on what the battery voltage DT points are), I would think something between 200 and 400 would be a more likely starting point for an injector of that size.

EDIT: Just saw that the ECMLink page recommends a deadtime of 0...not sure if I would trust that value though.
 
Last edited by a moderator:
ok new log, revisions made, global -18, fp back down to 37psi, new log items. fwiw car has 272s, also the isc and fiav has been deleted (sorry for not stating that at the beginning)
 
The O2 sensor is working... it's just confused as to when it should be working. AirFlowPerRev is very low, and CombinedFT is pretty much maxed unless you open the throttle a bit... so I think you need to do some basic idle tuning to get things in the ball park first.

BTW - Why (and how) was the ICS deleted?
 
I got the car with it deleted, it has a blockoff plate on the bottom of the tb, I asked why it was done and was told because the car was to be a spring/summer weekend warrior of sorts. I thought the o2 should be cycling during idle in closed loop? It seems to only cycle when the car is held @ a rpm. Any suggestions on where to start with the idle tuning? It came with the stock injectors, 2g maf and safc (all have been removed)
 
Gotcha I'll start from the beginning tomorrow, after just alittle browsing on those links I can only assume by looking at how far my logs are off that's its screwing up my 02 readings
 
Support Vendors who Support the DSM Community
Boosted Fabrication ECM Tuning ExtremePSI Fuel Injector Clinic Innovation Products Jacks Transmissions JNZ Tuning Kiggly Racing Morrison Fabrications MyMitsubishiStore.com RixRacing RockAuto RTM Racing STM Tuned

Latest posts

Build Thread Updates

Vendor Updates

Latest Classifieds

Back
Top