brahm

I was under the impression that once my car enters closed loop it should stay there? Is this wrong, as my car will go into closed loop for maybe 10-20 seconds then jump back out. It seems to also only go into closer loop if I entice via higher rpms. Is this normal? I was under the impression once everything heated up it stayed there? I can link up a DataMaster file if that will help.

WS6T3RROR

It should stay in closed loop unless there is a bad sensor or something else wrong. Post the file and if you can a copy of your tune.

brahm

Thank you for the response here are the files.

www.brahmgoodis.com/xfer/bintunebrahm.zip

MikeGyver

Thats weird. Why is the Data error indicator flashing randomly in datamasters? A couple of times it looked like the O2's weren't cycling low enough so it went back into Open Loop. The 'low res fail' data trouble code needs to be resolved. Pull the foot long pigtail wore out of the optispark and make sure all the pins on both ends are making good contact. Also your closed TPS voltage might be set too high.

brahm

Thanks again for your feedback. I don't know why or how, but my laptop decided to play nice today so I was able to do a much better pull on the way home from work. I apologize if this is a bit excessive but I've never been able to pull data when I was actually driving the car the previous datamaster pulls were the car in park, and me revving it to 3k. This file I made on the way home from work, it's got about 20 mins worth a data and all the conditions I normally drive under, starts off cold, then a little "city", then freeway cruising, as well as putting it under load on the freeway, and finally a test launch (in a secluded area ) after that a bit of low speed freeway driving.

http://www.brahmgoodis.com/xfer/brahmfulllog.zip

Things I noticed.
It only dropped out of Closed loop when I came to stops @ lights, the BPW mS would randomly turn yellow and go to 0.00, the CCP DC, and the EGR DC would hit 100.0 and turn yellow, the trim was all over the place to.

I'm still just a novice when it comes to figure out what the heck all this means so any advice and help is greatly appreciated.

In direct response to your questions/comments. I'm not sure what's up with the 02's they are brand new delteqs I put them in on Saturday, I also replaced my harness which was previously spliced with extensions so all the wires are clean now. They are both located right after the collector on my headers before my X pipe.

What is a Low Res Fail? (will google) but I'm not seeing that code, I cleared all the codes before this test I see an 11, 26, and 97. the MPH seems to be getting noticed by the PCM though as I was driving I could watch it in freescan so I'm not sure what is up with the VSS. This time around it seems the dataconnection was alot more stable, but it did still drop at times.

Thanks again, and I'll yank the opti cable toss some dialectic on it, and put it back in. As far as the TPS volts what should they be?

MikeGyver

I saw the low res fail code in the very first datalog you posted. It means it's not getting distributor reference pulses from the otpispark for some reason.

When the Bpw goes to 0 and yellow it's cuz the engine has gone into deceleration fuel cutoff (DFCO).

Is the VSS error causing the trans to shift like crap?
My closed TPS is like .57v. Have you opened the idle set screw?

At 424seconds it went back to open loop for fueling because the O2's stopped cycling. Are their heating elements working? It almost looks like the heater isn't working and it's relying on exhaust heat (off idle).

brahm

Thanks again for your response,
Could the Low Res, and VSS issue be due to the Low volts I'm getting across the board, could that also because the heating elements to not work right?

They are brand new 02s, and the wiring is solid. I noticed I'm getting between 10.9v and 11.6, with a multimeter @ the battery with the car off i get 13.6, and with it running and a quick rev to excite the alternator I get 15+.

As far as shifting, it seems good as far as I can tell, I bought this tranny of a member here and haven't put that much time on it, it's always been somewhat firm. (not like race firm but a good shift). The car in general is running better then it ever has, which makes me wonder how it will run if I can get the last of these kinks out

brahm

ok so I re-wired how I was powering the car.. I am now getting 13.6v via the pcm but this brought up another question please see.

https://www.camaroz28.com/forums/sho...37#post6080037

bobdec

Summing up some questions..
1 - yes low voltage below 10V to PCM can cause weird types of failures
2- VSS failures will put the 4l60E into 3rd gear and alter the tranny line pressure
3- VSS (speed) readings are used to control DFCO, erroneous reading could cause false DFCO.
4- I added a response to your other post
5- Alternator should go to 13.8 +/- .5 at high RPM, but 15 is sort of high, keep an eye on it.

brahm

Thanks you again for your responses Bob, I'm hoping re-wiring the PCM to get proper volts will clear the VSS errors, I'll find out today after work. The alternator was staying in the 13s via the PCM but was only reading 15 @ the battery level after I excited it, I believe it was just charging but I will keep my eye on it. I'm almost done with my re-wire this time soldering, no twists and tape haha.. Thanks again everybody for your help I'm looking to take here about 1000 miles this weekend, and I've got my fingers crossed

Mike, good call on the idle screw! I had it way up from when I still had some other issues and couldn't get the car to stay running when I came to a stop after it being hot. I cranked her back down and she is holding great (I also get that "sucking" noise coming from the filter now )