Closed loop problems

PR8urvtec · Post by **PR8urvtec** » Fri Jun 05, 2009 9:25 am

Ok,

The problem I am having is with the fuel leaning out when im in closed loop. This only happens with the ECU set to closed look. While in open loop the car drives good.

What seems to be happening is, while im cruising in the car the feul seems to just drop off when the pedal gets steady. Meaning I'm not on the pedal or off the pedal. The fuel will come back when I push the gas a little bit but will die out when the air levels out and just cruising.

I have read in another thread that there is min. short term and maximum short term adj. What does this do? I have not messed with it and looked at other turbo tunes and base maps of the same engine and none were changed.

If you need a datalog file and tables posted I will get them up later. I cant do that on the work computer.

I will also ask that when I post the logs and tables if someone could give me some more direction.

I feel like my engine startes to miss a little or det. after 5500 rpm. Is this an ignition problem? I have not messed with the ignition tables yet. I have another copy of my tune with the ignition retarted about 2* at 5000k rpm and up. I was going to try that out and see what it does. This is a learning experience and am using this on a stock integra ls engine. So if I have a mishap it's ok.But would like to get it right so I can drop the big one in.

Thanks for any help.
Ryan

Ps: the help menus are looking good. Did you guys add some info to it?

Turbo-LS · Post by **Turbo-LS** » Fri Jun 05, 2009 11:59 am

Not that this fixes your closed loop probelm but i have always run my cars open loop and any car ive tuned. i never put them back into closed loop and never had an issue. if its tuned properly it shouldnt need anythign more than intake temp corrections adjustment as the weather changes.

PR8urvtec · Post by **PR8urvtec** » Fri Jun 05, 2009 12:04 pm

Hmmm... I'm still learning the program and tuning. I got the fuel tuning down but I still need to learn the ignition timing.

It does seem to be running fine right now in open loop. I'm just not sure what I need to do to make the closed loop option work with my tune.

Turbo-LS · Post by **Turbo-LS** » Fri Jun 05, 2009 12:06 pm

Ive trried to use closed loop a few times and was always very unsuccesful so i stoppe bothering. LOL good luck with it

PR8urvtec · Post by **PR8urvtec** » Fri Jun 05, 2009 12:09 pm

Thanks for the input. If it's fine how it is then it's all good. What turbo are you using? I have a GT2871r on my ls engine.

Turbo-LS · Post by **Turbo-LS** » Fri Jun 05, 2009 12:22 pm

I dont run an LS anymore other than a crank & final drive & 5th gear . I used to be big into the LS scene but went to the dark said of vtec LOL. I was running a gt35/t67 though at one point in a hatch with a build LS.

Currently running sc63 .82 turbine stage 5 wheel on piston/rod stroked gsr with gsr rods and spr ls pistons its roughly 10.6:1 compression matted to an SPA top mount manifold. car runs strong

Are you running a P8R head?

Post by **Spunkster** » Fri Jun 05, 2009 12:44 pm

If a car is properly tuned it will run very well in closed loop. It will only have issues if the part throttle tuning is not done properly.

This is why the PLX widebands work so well, they have both wideband and narrowband signals output to the ECU at the same time from just one sensor.

PR8urvtec · Post by **PR8urvtec** » Fri Jun 05, 2009 1:20 pm

Nice, I didn't think the valve reliefs worked with the vtec head but I remember people with lsvtec's running them.

I don't have the PR8 head on it just yet. That is on a 2.0L that im putting together. I wanted to get some nice camsin there but don't really know what valve lash to use with that head. I'm not sure how I will figure that one out.

LS block bored to 84mm
sleeved
PR8 head
crower cams valve springs retainers.
GSR tranny w LSD

All in my super sleeper EG sedan.

I used to be all about all motor power. I had a EF hb, CRX, and EF sedan before the EG. I love those cars. Sold the CRX to my brother. I had a GSR engine w USDM type R pistons, stock head, w/ a B16 cable tranny in it. I was beating 350z's mustang GT's all over the place. People always thought it had nitrous on it lol. My brother is building a LS vtec right now for the rex.

GSR block LS crank
eagle rods
B16 head w/ skunk 2 pro 2 cams, dual VS, titanium retainers
same B16 tranny
with I think he said P30 pistons w/ a aftermarket headgasket

He's looking for like a 12.0 static compression ratio.

w/ the basic bolt ons I/H/E and a hondata S300 unit it should be pretty sweet to drive. It's a DX model so it's pretty light.

Any time with your setup(s)?

PR8urvtec · Post by **PR8urvtec** » Fri Jun 05, 2009 1:26 pm

Spunkster wrote:It a car is properly tuned it will run very well in closed loop. It will only have issues if the part throttle tuning is not done properly.

This is why the PLX widebands work so well, they have both wideband and narrowband signals output to the ECU at the same time from just one sensor.

Ahhh... ok... I will have to invest in that brand. So, I shouldnt have to change anything under the min/max short term adj if the part throttle is tuned properly. I am going to retune the car in a few days. Read over the tech articles and see what makes more sense since I have been messing with the program more.

Thanks
Ryan

Turbo-LS · Post by **Turbo-LS** » Fri Jun 05, 2009 6:23 pm

The valve lash as in clearence adjustment? for crowers its .007 on intake and .008 exhaust on a cold motor. IMO get rid of the crowers and get JG303 cams from jgengine dynamics. best LS cam ive run a few crowers and the jg303's. the jg's kick azz. and pull to like 8600

Jaker · Post by **Jaker** » Sun Jun 07, 2009 9:06 pm

Did you ever consider the possibility that your O2 sensor is failing? This could lead to the behaviour that you've described. It doesn't always kick a code.

PR8urvtec · Post by **PR8urvtec** » Mon Jun 08, 2009 5:56 am

I know the 02 is old but im sure it is still good. It was a problem with the MAP tuning. I went ahead and retuned it using a stock LS map w/ boost tables. Just sorted out my fuel in the boosted section and lef the part throttle pretty much stock. I still have a little fine tuning im sure I can do on the overall matrix but I got it running good in closed loop now. It stays in the 14.6-15.0 range.

Thanks for the help.
Ryan

PR8urvtec · Post by **PR8urvtec** » Thu Jun 11, 2009 7:52 am

Ok,

The car was running good and I have not changed anything in the tune over the passed few days. But i'm having the same problems again. Whe ever I try to steady out and cruise on the gas pedal it leans out and the car losses power until I push the gas more to speed up and then it leans out again when it stabilizes. Does anyone have any ideas?

The tune is really not that far from stock. In fact the only thing I really changed from the stock tune was the columns in boost. I took some fuel out there. The rest of the tune is stock LS. So, i'm wondering why it wont run properly in closed loop if thats how it runs from factory.

Thanks for any help,
Ryan

XPEHODATA · Post by **XPEHODATA** » Thu Jun 11, 2009 4:56 pm

I have this trouble on some ECUs. It leans in closed loop, but in open loop AFR is great. On some ECUs this bug is absent.
At b16 engine I just added about 30 points to fuel maps, not percents, to all cells when in closed loop. And AFR was good and not leaning.

When I used base map P30 (not hondata S300) I have this bug too. Tuned maps in open loop not the same with closed loop. I was enable "debug mode" with open loop together and maps was the same in closed loop.