350 Vortec wi th 454 TBI running pig rich

[rsicard]

Homemade pin tool. It is a piece of solid copper wire like used in grounding a meter base for electrical. 6ga solid. I drilled a small hole in one end and inserted a header pin from a piece of scrap electronics. Soldered the pin in and viola! The tool was dipped in liquid tin to slow the tarnishing of the copper but it isn't needed

Is this the extraction or insertion tool for ECU connector pins/contacts?

[rsicard]

Balancer inertia ring slipped? Check TDC mark with a piston stop in the spark plug hole on #1 cylinder. If the mark on the balancer lines up with 0deg mark on the timing cover, and the piston is at TDC on #1, the inertia ring has not slipped. Unplug bypass wire and set the distributor to 0 degrees advance with the engine idling with the timing light. Shut off engine and pull battery power to the ecm. Plug bypass wire back up. Reconnect battery. Restart engine and look at timing with light and compare to tunerpro. What ignition module are you running in the distributor? With all of the knock counts in the datalog, your ecm is retarding the timing (just a few degrees). Do you have the proper knock sensor installed? Knock sensor should be for a 1993,1994 or 1995 5.7 truck with ecm controlled auto transmission. The manual transmission sensor is different. Do you have the wire from the knock sensor tied to ECM pin B15? If you want to disable the knock sensor, set the Minimum Temperature for Knock Retard (under Knock Retard Parameters in Parameter Category View) to max which is 151.3C and burn the bin a chip or upload it to the emulator. Triple check your wiring from the distributor to the ecm. How close are your plug wires to your test stand harness? I saw some glitches in your datalog while replaying it. Is your timing chain new? I use Advanced $0D TP5 v251.xdf and $0D-16197427-V5.7.adx . These two files can be found here: http://www.gearhead-efi.com/Fuel-Inj...Information-0D . There are just a lot of different things that can cause your issues. I am using a 16197427 in my jeep. I have not seen the timing issues you have with my setup. I traced each wire and labeled them as I built the harness. I have patched my bin to control the electric fan and by following the instructions and wiring diagrams on this and other sites, everything has worked. I suggest you go over everything. If the timing advance at the balancer is that far off from what the tunerpro data shows, something is wrong whether it be electrical or mechanical.

I sincerely hope this helps

Brian

Could not locate $0D-16197427-5.7.adx at that link. One of the downloaded files must have been renamed, yet don't know which one>

[delcowizzid]

dont worry about rewiring tps etc if it looks good in the logs.get it running and get the IAC controlling idle it could be retarding timing to try bring the idle down cause the iac cant.and fit an unmodded ecu and memcal that hasnt been converted for TPI

[rsicard]

dont worry about rewiring tps etc if it looks good in the logs.get it running and get the IAC controlling idle it could be retarding timing to try bring the idle down cause the iac cant.and fit an unmodded ecu and memcal that hasnt been converted for TPI

Thanks for the very good advise. Will remove the jumpers from the sense resistors. Then run the engine and watch to see if IAC sets a fault. Also will see if it will idle down as it should. If all that is successful, then can fine tune the on-idle to near 14.7 AFR on Wide Band.

[sturgillbd]

It is an extraction tool. Here is the adx file.

[rsicard]

It is an extraction tool. Here is the adx file.

You have been a great help. Thanks again.

[PJG1173]

didn't see this mentioned but when you converted to the 454 TB did you transpose the 2 IAC wires required for the 454 IAC? trying to find my old diagrams from when I switched to a 454 TB and had issues.

[Nasty-Z]

didn't see this mentioned but when you converted to the 454 TB did you transpose the 2 IAC wires required for the 454 IAC? trying to find my old diagrams from when I switched to a 454 TB and had issues.

Good catch .

Here is the wiring info:

BBC IAC –
Pin A - Lt blu/blk - Coil A Low
Pin B - Lt blu/wht - Coil A High
Pin C - Lt grn/wht - Coil B High
Pin D - Lt grn/blk - Coil B Low
SBC IAC-
Pin A – Lt blu/wht – Coil A High
Pin B – Lt blu/blk – Coil A Low
Pin C – Lt grn/wht – Coil B High
Pin D – Lt grn/blk – Coil B Low


TOM

[rsicard]

didn't see this mentioned but when you converted to the 454 TB did you transpose the 2 IAC wires required for the 454 IAC? trying to find my old diagrams from when I switched to a 454 TB and had issues.

First I have to thank you for the kind response. The folks on this forum are fantastic. Everybody, keep up the good work. The harness on the engine run-in stand, was fabricated by Howell for the 454 TBI system using a 16197427 ECU. No alterations have been made to the harness with exception of putting dummy resistor in place of knock sensor to settle some radiated interference to the knock sensor input. Yet, thanks for the heads up as to the differences between IAC wiring differences between 7.4L and 5.7L throttle bodies. The 5.7L uses a square 4 pin connector, whereas the 7.4L uses a oval shaped in-line connector. Am contemplating having additional in-line connector for IAC interchange connections between the two different throttle bodies. Need to do this on the '95 pickup, as the factory harness has the square 4 pin connector that needs to be changed to the oval connector to use the 7.4L higher air flow throttle body.

[rsicard]

Good catch .

Here is the wiring info:

BBC IAC –
Pin A - Lt blu/blk - Coil A Low
Pin B - Lt blu/wht - Coil A High
Pin C - Lt grn/wht - Coil B High
Pin D - Lt grn/blk - Coil B Low
SBC IAC-
Pin A – Lt blu/wht – Coil A High
Pin B – Lt blu/blk – Coil A Low
Pin C – Lt grn/wht – Coil B High
Pin D – Lt grn/blk – Coil B Low


TOM

Tom: Thanks ever so much for your post. As explained before, the Vortec engine on the run-in stand is using a harness fabbed by Howell for the 7.4L TBI system using 16197427 ECU and throttle body. Again, thanks for the info posted.

Regards,
Rolly
Tucson, Arizona

[sturgillbd]

With the engine idling faster than what is commanded, the ecm is going to bottom out the IAC. The ecm is also going to retard the timing trying to slow the RPM as delcowizzid stated. Have you found any more vacuum leaks? I just disabled knock, egr, and ccp in this bin. I also pulled 35% from the entire Idle VE table. Load this in your APU1 or burn to a chip after warming the engine up. Datalog and post the results. Most of your BLM's from the last log I looked at were at 90. This should help. I assume no responsibility from the use of this file. I recommend you look at the file and do a bin compare in TUnerPro to see what I changed.

Brian

[rsicard]

With the engine idling faster than what is commanded, the ecm is going to bottom out the IAC. The ecm is also going to retard the timing trying to slow the RPM as delcowizzid stated. Have you found any more vacuum leaks? I just disabled knock, egr, and ccp in this bin. I also pulled 35% from the entire Idle VE table. Load this in your APU1 or burn to a chip after warming the engine up. Datalog and post the results. Most of your BLM's from the last log I looked at were at 90. This should help. I assume no responsibility from the use of this file. I recommend you look at the file and do a bin compare in TUnerPro to see what I changed.

Brian

Cannot say enough good words for all your help. Will try the modified BJYL binary. Picked BJYL as there was a comment I picked up that this is the binary for export Vortec TBI. If this is not proper, just let me know. Just checked the four wires from the distributor to the ECU. They are good. Also replaced the module in the distributor. Will search for more vacuum leaks. For the first time will try to do a bin compare. Thanks again.

[sturgillbd]

BJYL is a calibration (binary) for a 1995 5.7 TBI engine, auto transmission (4L60E) with a 3.08 rear axle ratio. It isn't for Vortec and is not export. Most export bins are not closed loop because they don't use an oxygen sensor. They don't use the oxygen sensor because of Leaded gasoline. BJYL is a good calibration to start with.

[rsicard]

BJYL is a calibration (binary) for a 1995 5.7 TBI engine, auto transmission (4L60E) with a 3.08 rear axle ratio. It isn't for Vortec and is not export. Most export bins are not closed loop because they don't use an oxygen sensor. They don't use the oxygen sensor because of Leaded gasoline. BJYL is a good calibration to start with.

As far as vacuum leaks are concerned, the same 4 barrel manifold and holley carb generated 19-20 inches of vacuum at idle with the LT-4 Hot Cam. Will hook up the vacuum gauge again to the 454 throttle body and see what it says.

[jim_in_dorris]

Riscard, I haven't seen anyone ask this question, so I figured I ought to. Are you using your wideband O2 sensor in place of the narrow band sensor as an input to the 7427?