Hello everyone, I just bought this 92 gta with a 5.0 and 5 speed. the guy i bought it from said it has a mild cam. The car ran pretty good but it smelled horribly of fuel, had a miss going down the highway and i could hear a vaccum leak. I took the TPI off and replaced all of the gaskets removed the egr (which wasnt even hand tight) and replaced all of the vacuum lines, capped off the egr vacuum ports and blocked off the egr on base plate. I went ahead and replaced the injectors with bosch III style and replaced all the sensors with new ac delco parts. Did a complete tune up that included a new distributor also.

Now, the car is hard to start but give it a little tap on the throttle and it'll idle great. I did some datalogging and it seems to never come out of open loop and the 02 status is always lean. The miss on the highway is gone now though.

I downloaded the best files that i could find online for xdf and bin to connect to get the data logging done and was going to hook up to do an emulation. I found a moates adaptor and downloaded the tune off of it. Everything is maxed out and i dont even know where to start. The bin i found online is called 122730_8D. i think i got it off of tunerpro's website. Can anyone confirm this is a good bin file to start with for my car?

5.0 TPI with a smallish sounding cam, bosch III injectors and headers.

Thanks for any info or advise.

 

Axxd might be a good start and add to ve . Might change voltage offsets first that will help a lot.
btw a bin is not needed to datalog wasn’t sure if that’s what you were asking.
If o2 is stuck in the .450mv area get a heated one.

 

Thanks for the advise. The computer from the car has a AXYC sticker on it and the chip in the memcal has the same number printed on it. Would this be the bin file i need to search for. i couldnt find anything like Axxd. The O2 sensor reading with the coolant temp at 220ish with the engine idling is at about 300 but the status shows ready. I was meaning the definitions file when i talked about datalogging.

 

http://gearhead-efi.com/Fuel-Injecti...Information-8D

 

Thanks, I signed up for this forum and i am awaiting permission to download this.

 

Programming the offsets should make a huge difference hopefully close to get o2 swings.

 

Recommend the following:
1) Have you extracted the BIN you're currently using. If so, please post it.
2) If not, then downloaded the referenced AXYC BIN and use it without making any changes.
3) Begin logging before starting the engine and log until into closed loop while driving for a while. Also let it idle in Closed loop for approx. 10 seconds. Don't stop logging until about 3-5 seconds after turning off the key.
4) Post the log (xdl file), or preferable, export to .csv and post that (Ctrl-E and follow prompts)
These steps will allow proper analysis of the issues.

Elky

 

Sorry im just now getting back to working on this issue. I finally found AXXD and used it added some to the VE table and will datalog this evening. I just dont know what this tune i attached ever did. I dont understand how it ever ran. To me is seems this is a work around that forces the use of limp mode or something. Take a look and see what you think.

 

With headers you need a 3 wire heated O2. I think the p/n for the Delco is AFS-74.

 

after changing the bin and modifying it to work with my injectors, it will go into closed loop now. Now that you say that about the o2 sensor though, will this cause it to read lean, or does the heated o2 sensor only help it to reach closed loop sooner?

 

Heated o2 sensor ensures engine remains in closed loop at idle and low RPM. Without one, idle/low RPM exhaust temps can remain inside the thresholds for CL and engine goes into OL. Sensor must provide a reading above approx. 700mv or below 200mv to allow CL.

 

Thanks i found that sensor on amazon for about 40 dollars. Ill go ahead and swap it see what happens.

 

 

Thanks, I was just looking for that part also. Should be here on Sunday. Any advice on where to go to get the switched 12v. Straight off the fuse panel or is there anything close by i can piggy back off of? I really appreciate yalls help.

 

Fuel pump feed at relay works for accessory power

 

I data logged today and going down the highway i noticed the oxygen sensor is bouncing from 8-900, the lean to rich status is doing the same. This is probably the surge ive been experiencing at highway speeds. Im not sure if it needs the heated sensor or just the new sensor all together! When i get the sensor in I will datalog again to see if the issue went away.

Thanks for the help

 

Is it going below the swing point or staying 8-900 mv ?

 

Im not sure what "swing point" means. It looks like it is ranging from high 700s up to max of 900 then dropping to 8 or 9 for a second then back up. Its pretty drastic like there is something wrong.
I also may need to check the fuel pressure again at the AFPR, but i dont think the readings should be falling that low. Its not long enough to cause the loop to change from closed to open though. It is enough to cause the engine to "surge" will the throttle is steady. I attached a zipped datalog file from the run if you care to look at it.

 

Blm averages 140-160 I’d try to work on recurving ve. Was voltage offsets and lower pw tuned ?

 

Please export the xdl log to a csv file and post it so it can be viewed in its entirely in Excel. That's the only way everything can be analyzed together. Otherwise with xdl, can only use TunerPro and analysis is limited.

 

I am running the bosche III injectors. I added about 15% to the existing VE table and removed about 25% from the voltage offset. i haven't touched the Pulse width yet. What would your recommend. I'm very new to this. I just want my car to run smooth and reliably. I am also running a miniram intake i bought from you lol! I noticed if i advance timing to about 10 degrees BTC the car accelarates a bit smoother especially around the 1800-2200 rpm area. I think i should add a bit more timing in that area but im not sure how to change that map. It idles better when at the 6 degrees but stumbles around 1800-2200. I am waiting to see what the 02 sensor might change for me as i did notice the 02 changing a lot there too.

 

Here is the csv file for the data log.

 

https://www.thirdgen.org/forums/diy-...gn-iii-pw.html

 

Some comments:

1. If engine is running with bin posted in #8 above, it's a miracle. All values are 0xFF. Please post bin that provided csv log in post #22. Also post your xdf file.
2. o2 sensor appears ok at idle and otherwise. Only had one OL period during idle at samples 1022-1051. Cross counts are being registered which indicates it's operating correctly.
3. BLM for the most part is pegged at 160 Lean or 108 rich. INT also lean in the 140s at idle but seems normal when running. Makes no sense.
4. Some PW values while not idling should be flooding a 5.0L engine. They don't seem to be what they should be.
5. Voltage at just over 13 seems low at both ignition switch and pump. Not related to how it runs, but just seems low.
6. IAC steps seems very low at idle (5-10) and TPS voltage too high (0.75). Have you adjusted the IAC and TPS according to factory procedures? Seems that is needed.
7. Forget messing with voltage offsets. They merely add fuel which does not seem to be needed.
8. With those injectors, recommend zeroing out the low PW table.

Having said that the o2 sensor "appears" OK above, changing it would seem warranted because in CL it's what determines the INT and BLM which are clearly not right, and BLM helps determines the PW.

 

Im not sure how the car ran with that earlier bin either. Here is the bin and xdf i used to create the log. the csv file seems to have filtered out a ton of stuff the actual datalog showed.

The car is a 92 speed density system so the TPS is non adjustable. i have re set the IAC many times i may be using an incorrect method though. "turn key to on, wait 30 seconds, unplug IAC, turn key to off plug in IAC" I may have to search the forums to find a better way.

I have set the low PW to zero and changed the voltage offsets to ones that tunedperformance steered me towards. The tune attached has neither of these done. I installed the tune late last night and the car idled fine and pulled into the garage with no issues. I still havent installed the new O2 sensor yet as today has been a busy day with the family.

Thanks again

 

Thanks for the correct BIN.

1)
Some TPS sensors (even for '92) may require slightly rounding out of the mounting holes to achieve the required voltage. The voltage cannot be higher than 0.78 volts at 0% TPS or the ECM will think the engine is not idling.

2)
Procedure for setting IAC is a bit more detailed than you described. Maybe you provided just a summary but see attached doc.

3)
With all respect to tunedperformance, all the voltage offsets do is add fuel. Unless you have a finely tuned race car, they are not your issue. You could use virtually any values because whatever the values are, they are added to the PW computed from your VE values. To begin, just keep offsets at some value and adjust VE to get proper BLM/AFR. See Post #1 here: https://www.thirdgen.org/forums/diy-...ml#post6322496