formulax4

iTrader: (1)

I have several datalog files that playback fine Using autoprom and tprt.The problem is I am an idiot! Im having a rich condition and cant seem to pin point the issue but im sure its in the tuning (new injectors,regulator,coolant temp ect) The car is an early 87 GTA.The issue is its getting 13mpg... Thing is its pretty much stock with the exception of .030 over bore and 24 lbs injectors and flattop pistons.Its a 5.7 tpi.When the car starts cold it will run like a dog blowing tons of black smoke out the pipes (super rich).Most of the time after it warms up a little it will stop the dumping gas and stop loping like it has a cam and smooth out and run decent. Still runs rich but decent.

I have datalogs from both when im having the super rich trouble and when its almost just fine. I was hoping someone could lent me a skilled set of eyes and a brain to match, and help make some sense of my data logs.

running 6E arap bin with the 1227165 adx.Im also available to for chat on this subject anytime on the phone.If you can lend a hand or have the time to help please please do. feel free to pm or post im up for any type of help.I can email or send however is best my data logs for viewing might even be able to host the datalogs somewhere thx!

RBob

iTrader: (1)

Double check the fuel pressure, the base ignition timing, and the injector specs.

The fuel pressure needs to be between 43 and 47 psi, vacuum line off engine running, warmed up.

Base ignition timing is 6* BTDC, warmed up, with the EST/BYPASS connector open.

Do a 'net search for the part numbers on the injectors. Verify that they are 24 #/hr at 3-bar (43.5 psi).

Then burn a PROM or such (whatever you are using to tune), for the injector flow rate set correctly.

Start data logging again and note the BLM value.

Note that you should also change the injector compensation tables to match the new injectors. Bug the injector supplier for this information.

RBob.

formulax4

iTrader: (1)

Thank you for the reply Rbob.The injectors are off my 85 corvette and are known working injectors,Fpr is at 43 its a bbk adjustable. timing is correct.same issues with the oem injectors and Fpr.I have set the injector size in the chip accordingly.I haven't changed the table for injectors tho.I thought it couldn't possibly be it because with the stock injectors its the same.

I definitely will adjust the tune for the injector tables to be modded thx.

The BLM are somewhat steady alot of the time but they take turns going up and down average in the 120's Int has dropped as far as 70 and the blm has dropped as low as 108 at the odd points.Block learn cell is anywhere from 2-13.The oxy sensor is in the 700-900+ range and in the 800-900 range alot.

Every sensor except knock has been replaced or swapped with known working ones.the 02 is known to work good as well on the 85.BUT For some odd reason the o2 reading will drop from 900+ to 888 then 444 then sometimes 0?I have tapped a new wire in at the ecm for the o2 without butchering the harness.Would you be able to veiw a few of my datalogs? Or any other ideas? Many thanks.

RBob

iTrader: (1)

Verify that the CTS reading from the ECM is correct. And that the MAF airflow is in the ballpark.

The O2 reading doesn't sound correct, however, it is blowing black smoke and the INT/BLMs drop like a rock once in closed loop. The O2 signal to the ECM (pin D6) also has a separate ground to the block. The O2 amplifier in the ECM is a differential input, and that ground is required.

The CTS & MAF have the most affect on the injector PW. I wouldn't be surprised if the ECM was bad. Check that the vacuum line to the FPR doesn't have fuel in it. Also check that the CCP line to the TB doesn't have fuel in it either.

RBob.

formulax4

iTrader: (1)

All checks out good. Interesting you mention maf as I had the code 33 plague awhile back.i figured it out but have sense added a microtech 1018 maf. The car never liked this model maf but I modded the tables and deleted the code 33.
Would the trans telling the ECM that 4th and 1st gear are both engaged mess with the load calculations the ECM calculates? Could someone help me understand how the lv8 is determined?

I'm just waiting on some parts from Dana at probuilt to arrive so I can put the trans back together and the 1st/4th gear pressure switch on the valve body will be fixed. I can't wait till the old slip-o-matic is healthy again. Ima search threads and reaD till my eyes are fried this weekend in the DIY prom area here in the forums. A lot of the best information available on the net is availible here at thirdgen.org. Very thankful to have found this site and to have your help Rbob and others.As soon as this tranny is done and the salt is gone off the streets I'll be able to gather more data logs.

Last questions here car seems to only load up bad enough to do the black smoke thing when it's cold out. It seems to aggravate the issue more. Why is that? Air density thing? Again thx.

RBob

iTrader: (1)

There isn't a 1st gear switch in the trans. There is also an option flag to let the ECM know whether the 4th gear switch is active high or active low (NC vs. NO). GM used both switches among the various 700R4s.

Most $6E XDF files have that option flag labeled as analog or digital MAF option. $6E only has code for an analog MAF. It is used to select between the two sets of TCC lockup tables.

I wouldn't be surprised if the microtech 1018 MAF is _way_ out of calibration.

Wow, just looked at the microtech 1018 MAF application guide. Way wrong there too. Also lists it for some of the '85 cars which used a digital MAF.

And it has an adjustable calibration feature. Since this is mostly a cold running issue, I wonder if the electronics is drifting with temperature.

RBob.

formulax4

iTrader: (1)

Interesting,I wonder why in my data scanner it shows 4th gear as engaged and 1st as engaged?It also has the neutral and park detection.
On the 85 vette it only has a place for the 4th gear to be engaged.The thing is my trans in the gta currently is a 85 trans.

Yeah the micro tech application chart is way wrong.I wonder what it would take to make the 1018 maf into an adjustable 1018a. I think ima go with a 1018a just due to the fact its easier to change the calibration on the maf than in the chip.The calibration we are talking about in the chip for maf to compensate for it being off is the maf tables am i correct? Also would you happen to know why im seeing the 1st gear engaged in my scanner?After this question i think that wraps it up for this thread awesome info thanks!