Or at least I feel stupid and am getting desperate.

We are heading to Moab on Thursday and the new FI is not running correctly.

What I had: It's a 79 SB350 (30 over) with cleaned up truck heads, around 9.25 compression, a Comp Cam Extreme Truck Cam (I can get you the info on the cam but it's basically just a little bit hotter then an RV cam and built for torque), and a performer intake.

What I put on: A stock 5.7L Chevy TBI setup with 7747 computer, no EGR or VVS.




I started out putting my O2 gauge on it (simple bar style with heated O2) and a fuel pressure gauge. I set the timing to stock and the fuel pressure to 15psi. It runs but is rich at idle, rich at WOT, rich when warming up, lean when running pretty much anywhere in closed loop and part throttle, and you can make it lean backfire thru the carb if you get on it to fast from idle.


I and a couple of friends looked it over, couldn't find anything wrong, and decided the motor is probably different enough that we needed to play with tuning it. So for the last month I have been trying to get some sort of dataloger to work with no luck. I have tried three different laptops, 2 ECU's, several ALDL cable setups, WinALDL and TunerProRT with no luck. I even had a friend who is a computer guru and tuned a 7747 setup for his IH Scout look at it and we just can't figure out why we can only get incomplete/unreasonable data out of it. However my father-n-law's fancy 4000$ code reader works just fine but obviously doesn't log data.


A couple of weeks ago I ordered up a Ostrich_2 emulator from Moates and installed it. I decided I am out of time for getting a data logger to work and I would try to tune it without the help of BLM's.... just like a carb.

Well the emulator works (to a point). I loaded a stock BIN and it ran exactly like it did with the stock chip. So today I tuned out the lean carb backfire, adjusted the WOT to an acceptable range. Then I started playing with the partial throttle lean issue.

Witch leads me to my first of I'm sure many questions: It seams no matter how high I push my VE1 and VE2 tables my O2 gauge still shows lean. Not totally lean for the most part and it tends to fluctuate and surge but I can't even get it to rich when I crank my VE's all the way up. It's like the VE tables are making no effect on the mixture. Do you guys have any ideas? I don't know where to even begin

I do have a small exhaust leak at the collector right above the O2 sensors but I can't see how it would effect this. Tomorrow I am going to fix the leak, put on a vacuum gauge, and replace the MAP sensor with a new one. I will also try it with the knock sensor off to see if something is setting it off and retarding the timing.



If I can't get this thing to work I'm going to have to either convert back to a carb, do a total swap of a 93 TBI motor from a running truck, or get a rental jeep for the trip and watch everyone else have fun on the hard stuff :no:

Thanks for any help you guys can give.
ROB

 

Are you using a socket booster with the Ostrich 2.0?

Is the CEL (Check Engine Light), when tuning, off, solid or flashing quickly?

In TP RT, you do have "emulation" selected, correct?

You have uploaded complete tables and/or bins to check to make sure the changes are taking effect?

What ADS/ADX file are you using to datalog?

I suspect that you may be in LHM (Limp Home Mode), since you say adjusting the VE table seems to do nothing, and that you get either no, or garbled data from the ALDL.

 

So am I correct in assuming that modifying the "open loop air fuel ratio vs. coolant temp" numbers is how you tune you're warm idle mixture? I have been searching and reading FAQ's for weeks and don't recall people talking about this...I am assuming it's so simple no one has to ask

 

Six_Shooter,
Yep I am using the socket booster (I think set to 24 pin)

I have not hooked the check engine light up but I don't think the code reader was saying there was a problem when we tried it a couple of weeks ago. However we just ran it on the trailer and didn't drive the rig around. I can do that tomorrow if you think it will help.

Yep I have emulation selected in TP-RT and it shows green on the bottom of the window. When I upload a newly modified BIN it says it's happy and the "verify emulator ram contents against current bin" button gives a valid response when the BIN is the same or modified.

Is the Verify button how I make sure it's taking effect? I know when I changed the "Power Enrichment" and "Accel. Enrichment" tables I got rid of my lean carb pop so it appears that's working correctly.

I tried the 42.ads and 1227747_42.ads files from TunerPro and the 1227747 one that came with WinALDL for dataloging. What's a ADX file?

Would the limp home mode be from the knock sensor thinking a collector leak is a knock? Is there any way to lock the limp home mode out? I am running stock timing and high octane fuel so I daught I am actually getting detonation. However the lean O2 gauge worries me; it's not a very expensive motor and it has a lot of hard years on it so it owes me nothing but I'd rather not burn it up if I can help it.

Thanks for the help!
ROB

 

While the CEL is a simple thing being "just" a light, it does help in verifying the state of the ECM, at a simple glance. A simple test light could be used temporaily. (I'm doing this in my Grandfather's '71 Chev pick currently). With the CEL, you can verify at key on, that the ECM is actually reading from the EPROM/Emulator, by the flash of the CEL, if it just comes on, with no flash, then you are in LHM, or at least not using the EPROM/emu the way it should be. Quickly flashing CEL indicates prom failure and in LHM.

Yeah, it sounds like you have emulation working correctly. Did you "disable checksum"? There is a setting in the preferences pop box under the emulation tab in TP RT V4, that allows you to set this "by upload", which means that as the bin is loaded to the Ostrich, this byte as set by the two boxes will be changed to disable checksum. For the '7747, it should be AA at 0x04. Once this is used, "verify emulator contents" will result in a "fail", since this one byte is different than the bin loaded, even if nothing else is changed. You can edit the bin manually using the hex editor, but lets keep things simple for now.

I believe those are the same ADS that I used. Yep, I just checked, and I used the 1227747_42.ads when I was tuning my friends truck, before we swapped to a '7730. I made some changes to the ads to add in a couple new values, but still the same basic file. Check to make sure the data pin, "M" I believe, is connected to the correct pin at the ECM, that the ground at the ALDL connector is good, etc. You can also try re-installing the original PROM, turning the key on, then check for TPS value changes, that the MAP read out looks correct etc, without starting. Just to make sure, you are clicking on the two blue arrows in the tool bar to connect to the ALDL stream, and that that preferences are set correctly, to the type of cable you are using, and com port?
An ADX file is the same as an ADS file, but is used with Tuner Pro V5.

No, LHM wouldn't be set by a single faulty sensor. That would throw a CEL, but not put the ECM into LHM.
Be careful with just unplugging the KS, this will usually cause max "knock retard", since the ECM then reads an open connection as lots of knock, or at least defaults to max retard when not seeing the KS, in addition to throwing a CEL. I don't recall if there is an easy way to disable the KS parameters with $42, but using a resitor of proper value, between the KS wire and ground will make a simple check to see if it's having an effect. IIRC you would need a 3.9K ohm resistor, but don't take that as correct, I'm trying to search my memory "archives". lol You should be able to use a DMM and measure between the pin and the base of the KS for a value that you can use for a resistor.

 

I did some searching about the "checksum"... still don't realy understand what it is but I didn't disable it.

People say to not disable it that way but to "Open the bin in TunerPro. Hit Ctrl + H to open the hex editor." and then put AA where it needs to go... from you're post it sounds like it should be on the first vertical line, 4 postions down. Does this sound correct? I know you say you want to keep this simple but it doesn't sound that complicated to do it this way.

I will do it the way you recomend for now.

Thanks for all the help!

 

From searching I think you can turn the knock sensor off by turning off the flag/switch "Err 43,ESC Error Enable" on the 42.xdf setup.

Also if I go to the 747.xdf they have a ton of Flags/Switches. the first bunch say "Checksum Enable and Flags - Bit 7-" and so on all the way down to "Bit-0". Do you think checking the "Bit-4" switch will result in disabling it the correct way? I wasn't using this xdf since it has so much extra stuff in it.

 

Thanks for the help Six_Shooter! I got it working (it was throwing itself into limp home mode) and got it close enought for our trip. I'm sure I will be back to learn more about tuning it better after we get home.

ROB