I've been having an issue with surging while cruising with partial throttle off and on for the past 2 years (I bought my EBL P4 in May of 2016 for reference). Some days it doesn't do it at all, other days its almost constant (of course its pretty much any day that I don't have my lapatop with me. Tonight I was FINALLY able to catch one on a datalog. For some reason there is one frame where my rpm jumps up to 6025, the air flow jumps to 214, and the DC on the injectors jumps to to roughly 30%. By next frame the numbers are back to reasonable values. There is no change in throttle, MAP, CTS, IAT, etc that would appear to be causing this. Attaching two separate occurrences of this issue. Any ideas?

 

The reason the airflow and DC% jumped is they are partially based on RPM. The ECM calculates RPM from the time between distributor reference pulses (DRPs). These are generated by the pickup coil and ICM in the distributor.

Also, make sure that the 4 wires between the distributor and ECM are away from any spark plug wires.

RBob.

 

Also, a partially shorted ignition coil can/will damage the ICM. I had the same issue with a cheap Spectra Premium distributor and a Pertronix Flame Thrower coil. Went with an AC Delco ICM which cured the surging. Then I had a stumble at idle, sprayed some water on the coil, not the wires, and she almost died. Found burn spots on the coil near the iron frame.

 

Just ordered the EBL P4 and just read thru both Intro to Tuning on Bob's website. Wow, got quite an education by going thru it with a fine tooth comb and lots of web searching to figure out what most of it meant.

Question for anyone who may know? Are the bin files that arrive with the EBL P4 highly modified and optimized to make a factory engine run better than what the factory provided? After some VE learns the engine should be running better than ever?

 

That is great, ir=t does take some time/effort to start to understand EFI.

Most of the supplied BINs are based on factory tunes. There are too many variables to be supplying modified hi-po tunes for folks. It is best to start with a known tune that is safe, and then go to a more performance tune.

RBob.

 

Is there a way to switch from bank to bank in the Flash-II without hooking it up to a lap top, maybe a momentary switch and a small digital display showing the bank #? Something like switching from tow/performance mode to MPG mode to valet?

 

You could wire the O2 sensor signal wires from each bank through a double pole double throw switch and the output from the switch goes to the ECM.

Once you flip the switch the ECM would display how its reaching to that side.

 

I believe he’s talking about bank tune switching. Switching the tune not each cylinder bank.

 

Ah ok...

 

Yes, bank tune switching, thanks.

 

Don't know if this is what you're looking for, but Dynamic EFI (RBob) used to sell these bank switchers for EBL Flash. You will see them for sale occasionally on this forum.

EBL Flash Switcher

 

Yes, that's exactly what I was thinking about,. Do you know if @RBob still has them? I looked at your link and on his website but I can't find where to drill down on it? Does anyone else happen to have one available?

Peter

 

We stopped building/selling them as the demand was quite low. Also, they only work with the previous EBL Flash system that was RS-232 based. Not the USB based ones we sell today.

RBob.

 

Bummer! So, there's no other solution?

 

A small tablet that runs the full version of Windows.

RBob.

 

Ha! Just purchased for my new overbuilt 383 install. My 870 ecm is incapable of a good tune. Several emails later. I get it. Awesome!

 

Hi, I'm new here to the 3rd gen forum. I actually I have a 1985 Vette with the EBL for 2 years. Recently, I had to rebuild the L98 engine and put an aluminum head 9.6:1 CR. I still in the calibration process. My idle is way too high. Hot engine, 950 RPM in parking and about 800-750 in "Drive". If I turn the idle screw to lower the revs, the engine revs are not steady and the engine stalls after 20 seconds or so.
The odd thing is in the WUD I see 0 steps. It doesn't if the engine is hot or cold. when the car is starts to move, the steps starting to climb from zero.
What do I miss? I got instructions from Bobr to verify the steps while in parking the IAC steps should be between 20 and 25.
Thanks

 

When I installed the EBL, I missed the fact that you need BAT power connected to the EBL as well as IGN. Besides forgetting any tuning, the IAC was not zeroing and parking after ignition was switched off, so it had no idea where it was; while it reported steps, they were incorrect. I couldn't get the EBL to control and bring the idle down.
You should be able to hear the IAC parking if your ear is anywhere near the TB after you remove IGN power. It sounds like you adjusted the throttle plate completely closed; I tried that too with the same results until I figured out the BAT/IGN stuff. Some folks use a .007 feeler gauge between the throttle plate and barrel to set the opening of the throttle plate at rest.

 

Terminal B1 and C16 is BAT. A6 is IGN. Not sure of your post.

 

Whats the closed throttle TPS? I feel your pain. Whats the fuel pressure? Is it lean? O2 is less than .450? Just bought a EBL for my 85 iroc..

 

Initially, I connected all three to IGN, which didn't let the IAC park correctly.

 

dont tell me, tell yariv.

 

Yariv, I think you need to set the throttle to let in a little air at idle; then the IAC can control the rest of the air to match the idle RPM and A/F ratio routines in the BIN.

 

I didn't have any issues with the old engine. maybe something happend to the IAC while the engine was out. I cleaned the TB while the IAC was attached.
I can verify, I didn't have any steps issue while standing/parking. I just checked the old logs.

 

TPI is prone to vacuum leaks.

 

As I just wrote. I checked with old engine logs. I didn't have any "steps" issues while standing/parking. when I closed a bit the idle screw while @ "P" to 900 RPMS, everything is great.

 

old engine logs.

 

The EBL is the same. wasn't replaced. I try to get another IAC.

 

Agree that you should check for vacuum leaks; In my case, the TB/manifold gasket was too thin and couldn't compensate for a slightly warped throttle body. A thicker gasket solved that. if air is getting into the engine anywhere except the IAC or throttle plates at idle, the EBL will try to slow the idle down by closing the IAC. If the IAC is at 0, it can't do anything more to reduce air. At that point, adjusting the throttle plate until it's completely closed will stall the engine. You might see fuel pooling above the plates.

 

So leaks after the TB? runners and or intake manifold? how can I check a leak from there?
to prevent the stall at idle (parking only). I raised the revs up to 900 by turn clockwise (close the screw that push the blade's lever). I let more air to get in through the blades, right? how does let more air in via the TB while idle effects the leak?
Thanks

 

Try this for finding vacuum leaks: https://www.corvetteforum.com/forums/c4-tech-performance/3263941-checking-for-vacuum-leaks-on-l98.html

"how does let more air in via the TB while idle effects the leak"

It's the other way around... If the throttle plates were fully closed and the engine stalled, you probably don't have any (or large) vacuum leaks and no air is bypassing the throttle plates via the IAC. There needs to be air entering through the IAC for the EBL to control idle speed.

Since you have already played with the idle screw, the best way to proceed is...
1. Pre-tune the throttle plate idle setting by using adjusting the throttle screw for a plate/barrel clearance of .007" with a feeler gauge.
2. Then follow the IAC/TB setting procedure: https://itstillruns.com/reset-baseli...i-7959677.html

See this article for more info, including info on IAC steps during cold start and warm running.
http://www.gmtuners.com/tech/TPS_IAC.htm

 

It appears the link to "itstillruns.com" is missing a step between 3 & 4 where you turn on the key allowing the IAC to close all the way, then pull the connector. At the bottom of the link to "gmtuners.com" is the right way to do it.

 

Thank you for that!

 

It's been a while since I last looked into this... Are there any inexpensive portable devices (like a tablet) that can run WUD, that people would recommend? I have an ancient laptop with all my tuning stuff on it, not sure it will even start anymore.

 

I just bought a old acer aspire off ebay. 100 bucks. Put in a solid state drive. Installed Win7. Although microsoft says it is no longer supported, you can find and absolutely need service pack 1 update. Works great.

 

I need some help! I just did a EBL FLASH-II change for an 85 TPI 98 Corvette. All went fine, except.. I have been getting a Code 21 TPS HIGH since the install 2 weeks ago, I tried everything with bobs help via email. Even changed out the TPS this morning with no change. So I started doing some wiring checks on the PIN swaps and what was being feed to the new ECU. The TPS ground wire is a BLK/PUPLE strip wire. Testing that wire to ground showed an open reading. SO this was my issue. I went back to the wire swaping list and found were this wire was pulled from the previous position and laid back and not used now. In the swap it said to move a BLK with into PIN A-11 and is labeled BLK/PUP. But the swap list puts a all BLK wire in A-11 not the BLK/PUP. I pulled the solid black from A-11 and inserted the BLK/PUP wire and GOLD! I now had TPS readings as I should. No more code 21.. But now she will not start and I have a Error code 23 IAT Low. From the wiring it shows all 3 the TPS/CTS/IAT use this pin for ground. Im thinking on my wiring the solid black is not all three GRNs but the solid black is the GRD for the IAC circuit and since I replaced it with the BLK/PUP wire Im loosing ground now to the IAC... Suggestions? Im dead in the water at work as the car will not start and sometimes Bob takes a say or so to answer, Its raining I dont wanna walk home LOL

 

Ok I made a post that seems to not have been approved yet so I'll post a follow up just in case it shows up.. Seems my 85 has 5 grounds off the sensors and the EBL has 4 pins. This left a floating ground doing nothing at the harness and no place to put it. With Bobr help we decided to tap into another ground. Presto, no more codes and the car is running great. I did 4 VE learns in the last couple of hours and now. And here is what Ive wound up with. If anyone wants to give a few tips ( with Newbie step by steps) I'm open! This was the last learn Corrections and the SA Main after flashed..

1985 L98 TPI,
BBK 48mm Throttle Body,
Summit SUM-1102 RV Cam.
3.07 Gear / Automatic
EBL Flash-II

 

I am running a EBL P4 on a 1992 Camaro with dual fans and A/C. Is there a way to have the ECM control the second fan based off of temp like the first fan but have it also still come on with the A/C?

Thanks

 

Yes, it is easy to do. Need a connector terminal and wire. Insert the terminal/wire into position F8 (yellow and/or lime green connector).

Then splice the other end into the wire to D12 (GRY on larger BLK connector). Note that D12 still goes out to the engine and into the ECM.

This way either: the ECM, head temperature switch, or A/C controls the secondary fan. AND, requests that the primary fan also runs.

RBob.

P.S. just wanted to add that this mod also works for stock '7730 $8D ECMs...

 

Win 10 laptop wil not communicate with my EBL P4. My old acer laptop running win vista started to act up and is not reliable so I replaced it with a newer acer running win 10. It has been refurbished and has a clean install of win 10. I downloaded tunerpro rt and the ebl wud software and the wud screen displays but it will communicate with the ebl. I tried different com ports and still no go. I tried uninstalling the program and still no good. Can anybody help? I can access the ebl with the old laptop but I am afraid it is going to crash at any time.

 

Use the Device Manager to see which port is assigned to the cable. No need to connect to the ECM, just plug the cable into the laptop.

If the driver is required can get it directly from the FTDI web site:

https://ftdichip.com/drivers/vcp-drivers/

RBob.

 

Thanks, I did some research and found out this laptop did not have any ports (Com & LPT) listed in device manager like my old laptop had. I went into the action menu and clicked on Add Legacy hardware and it added a com port to the device manager. Tomorrow I will plug into the EBL and do the key on engine off to see if will communicate. If not I will load the driver from the FTDI website. I will post my results tomorrow. I just checked device manager on the MSI laptop I am using to reply to your message and it also does not have any Com or LPT ports showing in device manager. Must be a win 10 issue. Both of these laptops came with Win 10 installed. My old laptop was a Vista machine. I borrowed a win 7 machine that had been upgraded to win 10 and it has the com ports listed in device manager.

 

Follow up, I downloaded the FTDI drivers and got the laptop to connect to the EBL. Thanks for the help and the links. Now I can resume tuning my Vortec TPI Caprice Landau.

 

You're welcome. Happy tuning...

RBob.

 

Yeah, it's a Win 10 thing. I have an HP laptop with Win 10 and it won't show any COM Ports until I plug my ALDL cable in to a USB port. Then the COM Port shows up in Device Manager.

 

Late last year I finished an engine swap on my 91 Caprice from an L03 to an L31-R (GM crate motor) and kept the TBI. Have chronicled the build on the ImpalaSS forum here.

This year I've spend tuning with the EBL. I don't get many opportunities to drive it due to work which is why it's taken ~10 months to get up to about 70 VE learns. Along the way I've learned some things on how best to do VE learns with WB (not NB) and went down some bunny trails a few times. Also found that the engine seems to like the ACDelco R42LTS plug instead of anything hotter.

At this point the car is running pretty well but seems to still be a bit rich in some areas. Additionally, I find idle to still be a bit rough. It doesn't surge (fixed that issue earlier) but I know it can be smoother. Attached is my latest bin and data log and I'm wondering if anyone would be willing to share some pointers on where to focus next. The attached data log covers a 3 VE learns that are "around town" driving to a few different stops. I believe I have the bin set up properly for VE learns (CCP off, EGR Off, both vacuum lines unplugged with the TBI capped). I've reset the IAC and set the throttle screw to make sure there wasn't any issue there.

I don't believe I have any mechanical issues as most things seem to be working with the exception of being rich and a little rough. I rebuilt the TBI at one point due to developing a fuel leak at the pressure regulator blockoff plate. One thing I'm considering checking in the rocker nuts/preload. I did a cam swap before installing the engine and changed rockers and springs. Am nearly positive I did the procedure correct with the recommended 0.5 - 0.75 turn preload. That being said, this is the first time I've done that work and don't trust that I didn't make a rookie mistake. Would welcome any thoughts on if that could be a cause for the way it's running.

My question is, should I just continue doing VE learns throughout the MAP/RPM scales until things start to stabilize and it runs smoothly everywhere? Is there anything else I should be looking at or changing (spark advance, acceleration enrichment, deceleration enleanment, etc.)?

Thanks in advance!

 

I have a question for you gurus. We've been having a discussion on another forum I'm on. On the 7747 based EBL Flash-II (or any other ECM/PCM) is the fuel pump turned on by the relay AND the Oil Pressure switch located near the dizzy? Some folks say the ECM only turns on the fuel pump relay to prime and while cranking, then shuts it off some time after the engine starts. Then the fuel pump is only fed 12V through the OP switch. This way, if the engine loses oil pressure it'll shut off, to save it from catastrophic failure. I'm thinking it's simply redundancy having them wired in parallel so either or both will keep the fuel pump running. TIA

 

I didn't think it was a debate. Looking at the wiring schematics it's a redundancy so the engine will stay running if the relay fails while driving.

 

Yeah, that's the thing - the schematic shows them wired in parallel but, what's to say the ECM doesn't shut off the fuel pump relay after the engine's running for a while? One guy there said "if I disconnect the OP switch while the engine is running, it'll die". I'm thinking "then something's wrong with your fuel pump relay." Is there anyway to dismantle the ECM's code to see what's supposed to happen?

 

Sounds more like the pump isn't powered by the relay at all, cranking till oil pressure gives the fuel pump power. Just a guess.