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XxSlowpokexX
04-10-2011, 08:14 PM
Well I forced open loop in my car and it till doesnt idle and seems like its dumping fuel.

It wil idle and start right up but once I give it gas it wont start easy again or idle.

So Hell. I was looking at different variable and it all looked greek to me.

So what exactly should I datalog that may help someone knowledgable figure out if I have a tune issue> Im in the rocess of hooking up my lc1 but that may not be done just yet.

Thanks guys

neverfastenough
04-11-2011, 09:57 AM
First, what was the point of forcing it open? And is this all cold start you are working with here?

XxSlowpokexX
04-11-2011, 12:26 PM
My car was running perfectly fine with the tune I have then some issues. I had the whoel top end of the engine apart and the issues still are there. Tested all sensors all came out fine. Checked for air leaks none.

Therefore I was hoping that forcing closed loop which I did would take teh computers learning out and just run off the tables that had originally worked...Unfortunately it didnt.

SO i want to data log variables that may give a hint as to whats going on here That being said It may tell me where to look..If not Im ripping it all apart again

S_Mazza
04-11-2011, 12:46 PM
My car was running perfectly fine with the tune I have then some issues. I had the whoel top end of the engine apart and the issues still are there. Tested all sensors all came out fine. Checked for air leaks none.

Therefore I was hoping that forcing closed loop which I did would take teh computers learning out and just run off the tables that had originally worked...Unfortunately it didnt.

SO i want to data log variables that may give a hint as to whats going on here That being said It may tell me where to look..If not Im ripping it all apart again

For starters, RPM, VMAF, SPARK, KMRF1 (spelling?), KMRF2, ECT, and ACT. The KMRF1 and KMRF2 are the short term fuel trims. This will show you whether the engine tends to run rich or lean as it is calibrated now. This will only work within the narrow band of the stock O2 sensors, but this is enough to show any major problems, except for full-throttle operation, where the commanded mixture is richer than stoichometric.

XxSlowpokexX
04-11-2011, 02:17 PM
full throttle it seems much better..But I wont take the car anywhere as its a pain to drive....When I data log however I want to get a log at idle when it idles..One cruising part throttle then one WOT..

If nothing can be figured out I will tear the blower and intake off and redo. Smok test showed only slight leakage at TB linkage and my complete IC setup help 22psi for over 15 min....Doesnt mean I dont have a leak on the return adaptor or the inlet I supposse Or even teh hat adapter plate on the AR

S_Mazza
04-11-2011, 04:26 PM
full throttle it seems much better..But I wont take the car anywhere as its a pain to drive....When I data log however I want to get a log at idle when it idles..One cruising part throttle then one WOT..

You can leave it in the same log file, so you don't have to worry about switching the datalog on and off while driving. Then just find the sections you want and "save as" each to a smaller file if you want.

I forgot to mention, if you look at the Dashboard screen, you can check all your sensor outputs right there. It's not much use for the O2s because they switch so much, but you can check the TPS, ECT, ACT, and BAP voltages, and see if there is any obvious problem with one of those sensors.

While idling, you could take a screenshot of the dashboard and post it here. ("Printscreen" key to take the shot, then open "Paint", "GIMP", or whatever image program you have, and paste it in as a new image.)

A quick check of the MAF transfer function can be done by taking the entire log file and sorting all the data by the VMAF value. Then you can take a look at the short term fuel trim (KAMRF) for each bank at the VMAF values that are mapped in the transfer function, like 0.6V, 0.8V, 0.9V, 1V, 1.2V, etc.. This method isn't perfect, as it mixes and matches readings from different times in the drive cycle, temperature readings, and load values, but it is a quick way to see if you are rich or lean.

XxSlowpokexX
04-11-2011, 06:06 PM
Thanks. This weekend I think I have a full saturday to work on it. Casey helped me get it all operational yesterday as I was heving a few issues but now its reading just fine. Maybe ill get a chance to install the LC1 as well