V3 idle tuning

[tkstoygsx]

Ok guys, having a severely horrible time trying to get my idle cruise tune dialed in. Before I start I will post the info on the car:

1993 talon tsi
fresh 6 bolt with 260 miles and 150psi across the board as of yesterday
oem bottom end rebuild
mild built head with delta 272 cams, MAP beehive and valves
head studs and SCE Titan HG
Stock 450cc and stock MAF

zero boost leaks as of this past week
rebuilt throttle body from throttlebodies.com
properly adjusted TPS
properly adjusted throttle cable
Mechanical timing is spot on and the base it right at 5* when grounded in link.

I am having a hell of a time getting this tune down just for idle and cruise. First off, I am having a horrible time getting the wideband to read correctly and match the AFREST value. I have tried using the values in the paperwork that came with the gauge and tweaking them a bit and nothing seams to help. Its a Digital AEM Wideband gauge and I'm pretty sure I have everything set correctly but may be missing something.

Secondly, I know that the car needs to idle up a little higher then normal when first started but mines idles at about 2000 rpm until its fully warmed up. My ISC was supposed to be good when I got the throttle body back from Steve at TB.com and was tested so I don't think that's the issue however I am having the hardest time getting the ISCPOSITION to 30 when idling. Its seems to stay around 14-20.

Also , when I adjust my maf comp to lower the airflowperrev my combinedft goes way up to around +18 and then raising the deatime makes little to no difference. What could be causing this? Could it be a bad maf?

Those are the starting questions and I will post more issues once these are resolved! Thanks in advance!!

 

[gofer]

You cant post a log that you did while you were tuning because it only captures the settings when you began capturing it. Post a log of the idle after you've made your adjustments to globals/deadtimes/mafcomp.

 

[tkstoygsx]

Ok my bad. i will get another capture done this evening to post up! Thanks

 

[tkstoygsx]

Also had a quick question in regards to why my o2 sensor reading doesnt vary more than just .20 - .80 I thought it was supposed to read all over when operation properly. This is a brand new sensor as of 260 miles ago!

 

[c2ypt1c]

Also had a quick question in regards to why my o2 sensor reading doesnt vary more than just .20 - .80 I thought it was supposed to read all over when operation properly. This is a brand new sensor as of 260 miles ago!

Link is simulating a narrowband signal with your aem wideband. .20-.80v is the simulated narrowband voltage range and it's currently set to occilate at 2.33v (raw voltage from wideband). The ecu uses the narrowband signal (named FrontO2 in Link) for closed-loop operation. Looks like it's working fine to me.

If you want to look at the raw wideband voltage, go to displayed values->raw value->RawFrO2VoltsInput. Notice how FrontO2 is switching high and low at around 2.33 raw volts. You can actually set this voltage value under the NBO2 sim page in link. You can read more about it on this page:
v3narrowbandsim [ECMTuning - wiki]

 

[tkstoygsx]

Link is simulating a narrowband signal with your aem wideband. .20-.80v is the simulated narrowband voltage range and it's currently set to occilate at 2.33v (raw voltage from wideband). The ecu uses the narrowband signal (named FrontO2 in Link) for closed-loop operation. Looks like it's working fine to me.

If you want to look at the raw wideband voltage, go to displayed values->raw value->RawFrO2VoltsInput. Notice how FrontO2 is switching high and low at around 2.33 raw volts. You can actually set this voltage value under the NBO2 sim page in link. You can read more about it on this page:
v3narrowbandsim [ECMTuning - wiki]

Thanks for the response and I have read through the ECMTUNING wiki page just had my doubts. Guess im just paranoid at the moment. I will be posting another log once i get my idle surge issue figured out. I think i may need to reset my idle switch and cable positioning now that i have set the tps properly. Also could test the ISC to be sure its good even though its from throttlebodies.com

 

[tkstoygsx]

Also had another quick question before making any changes to the idle tune. Since i am running a large camshaft set what would a good target AIRFLOWPERREV be. I noticed in the ECMLINK DEMO vids that he is aiming for .25/.26 but im unsure if this would be a good goal to hit with the larger cams!

 

[lil corb]

Also had another quick question before making any changes to the idle tune. Since i am running a large camshaft set what would a good target AIRFLOWPERREV be. I noticed in the ECMLINK DEMO vids that he is aiming for .25/.26 but im unsure if this would be a good goal to hit with the larger cams!

This seems to be the answer no one knows for sure. I am at .32-.35 with FP2s (comp 101200 cams) I cant get it to .25-.27 without everything else going to crap and car running like crap.

 

[gofer]

Airflowperrev is roughly proportional to engine displacement.

(current engine displacement / 2.0) x 0.25 = target idle airflowperrev​

That being said, on a 2.0l you should target 0.25gm/rev no matter what your cam setup.


Since you've got stock injectors there will be no global fuel adjustment, just adjust your MAFComp sliders to bring in AirflowPerRev then adjust your injector deadtimes to get CombinedFT's to hover around 0% (+/- 8%).

 

[SonySlave]

I know I'm going to get flamed again for this but here goes...

I'll put money down that you're issue is the re-ground Delta cams. I am not surprised that you are having idle issues. Delta Cams is local to the Seattle area where I lived my whole life before moving to Maryland. A lot of people up there have used these cams in the past 15 years and every single one I know had abnormal vacuum issues that usually affected idle and never made great power. I personally ran both Delta's 272 and 280 re-grinds, both with nothing but problems with idle and cruising. My first and only recommendation would be to change cams. A nice set of FP2s or GSC S1 or S2s would be where I'd go. Put some real cams in the cars and I guarantee your tuning issues will disappear.

Anyway, I'll get off my soapbox...