closed loop cruising problem.. need help please

s300 and SManager software questions & answers
peasly23
Posts: 79
Joined: Tue Sep 25, 2007 9:58 am

Post by peasly23 »

Just to get in on the subject... I am currently experiencing a similar problem that I am trying to narrow down. While I am at low load and slight throttle, my car slows/surges slightly and the air/fuel ratios go slightly richer, not leaner. I also don't have an older version of Smanager to test with.

frank316
Posts: 2
Joined: Thu May 27, 2010 10:13 am

Post by frank316 »

I'm kind of having the same problem as most here. At part throttle,(anything below 10 inches of vaccum) the car sometimes runs right, but more often that not it leans out to like 17-18 to 1 and starts missfiring, as soon as i get it above 10 inches of vac it quits for awhile.. It also only does it when the car is warm,(IE takes at least 15 minutes of driving to make it start doing it) but i currently don't have closed loop on, its runnin in open loop all the time. But it sounds liek the same problem these guys are having.

peasly23
Posts: 79
Joined: Tue Sep 25, 2007 9:58 am

Post by peasly23 »

I just did a couple of test drives and I am in fact having the same problem but only in closed loop. Everything was working fine before the upgrade to the newest version(s). My last update was before October 2009. My A/F ratios definately jump between richer and leaner while driving in closed loop only.

I switched to open loop and the problem disapeared.

Please help!

nathanlol
Posts: 2
Joined: Sat Jun 12, 2010 12:02 am

Post by nathanlol »

peasly23 wrote:I just did a couple of test drives and I am in fact having the same problem but only in closed loop. Everything was working fine before the upgrade to the newest version(s). My last update was before October 2009. My A/F ratios definately jump between richer and leaner while driving in closed loop only.

I switched to open loop and the problem disapeared.

Please help!
same problem over here.. open loop is perfectly fine but in closed loop when crusing at the moderate low throttle it would sweep from rich to lean every few secs.
so i tested to see if ecu was giving out any volts threw the o2 plug and it was dead. so i got a new working ecu.. things are much much better.. car is running smoother but on the highway this time its much less.. it still sweeps back and fourth but much smaller ranges from 14. - 16 every few secs. im on a aem wideband. any knowledge folks?

peasly23
Posts: 79
Joined: Tue Sep 25, 2007 9:58 am

Post by peasly23 »

You have to change the "rate of change" section to substantially lower numbers. They must have changed this section in the newer versions. Don't just guess... find Spunkster's calibration and use his numbers.

I'm pissed they changed this and didn't tell anyone.

on1
Posts: 1
Joined: Fri May 20, 2011 12:32 am

Re: closed loop cruising problem.. need help please

Post by on1 »

well his numbers make the afr jump all over too. i got the same problem. either u set high and it over compensates or u set it low and it takes forever to get to the perfect stoichiometric mix. it seems with these controls u cant get it right. i know its not my engine having a mechanical problem. vacuum leak, misfire etc. because i can set it in open loop and its smooth. the only thing is, i am running a base map its not tuned so its rich. if i turn the closed loop on the ecu it is trying to adjust to get to the widebands target voltage but its over shooting. if you have a 100 for your fast rich to lean or lean to rich it add 100% of fuel. then it sees "whoa im way to rich and over compensates again. this is why the afr jumps all over. sure u can set it reallly low but then if u jump on it and it and afr drops to 12.5 and then u press and hold the throttle evenly it will take a while to get back to your 14.7 to 1 afr. so my question is how do i get an older version of smanager where this not adjustable and honda engineers have already designed a system that was working fine. why would they want to make closed loop adjustable. closed loop is for idle and light throttle applications.

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