1227165 Running 12P for a GM 2.5L Iron Duke with Turbo

American GM ECUs and PCMs
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Joined: Mon Apr 03, 2017 2:33 am

Re: 1227165 Running 12P for a GM 2.5L Iron Duke with Turbo

Postby Mark_ZZ3 » Thu Apr 13, 2017 2:55 pm

Holden202T wrote:post your bin and I can have a look....

also how do you have the relay wired up to the flex output ?


I use A2 as the connection (ground) to the relay. This was the EGR solenoid in the truck ... so easy to reuse the wiring. The relay is a stock volvo part specific for the boost control.

Mark.

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Re: 1227165 Running 12P for a GM 2.5L Iron Duke with Turbo

Postby Holden202T » Thu Apr 13, 2017 3:55 pm

Ok I've updated for flex b setup with RPM v's MAP axis and its whatever settings you already had in your tune in the flex b table.

this is how I set it.

alex - flex1.jpg
alex - flex1.jpg (81.23 KiB) Viewed 345 times

alex - flex.jpg
alex - flex.jpg (331.81 KiB) Viewed 345 times

So as you can see, the relay should turn on at 3023rpm and over 150kpa ... obviously you can change the table values to suit the map and rpm you want for no/off points.

I've also attached the modified bin file, and xdf file to suit.

Alex - $12P - Flex b.XDF
(377.14 KiB) Downloaded 14 times

Alex 12P 2 Bar 1.0-flexb.bin
(32 KiB) Downloaded 14 times

just for your knowledge, you need to load your cal/bin file in the flex table editor, then select the flex a/b/c/d etc then change all the settings to suit what you want, then from there you can

1. save the cal/bin file (this then needs to be uploaded to the computer to take effect)
2. modify the XDF which will give you the correct axis info and update the table name with what axis type (rpm/map/cts/tps etc)

make sure once you have done this you use that xdf to edit, and also make sure you use that bin file to load when you make changes, if you go back to an earlier bin file you will overite all the settings.

As i understand it the reason the flex table editor is in the ose flash tool and not part of tunerpro is that it needs a lot of special selections and coding to make it work which just isn't possible to do in tunerpro tables/flags etc. normally in tunerpro XDF the table settings are something that is hard coded and doersn't ever change once its been setup, so to allow all the axis changes needed in the flex tables that was the answer.

Posts: 17
Joined: Mon Apr 03, 2017 2:33 am

Re: 1227165 Running 12P for a GM 2.5L Iron Duke with Turbo

Postby Mark_ZZ3 » Thu Apr 13, 2017 11:52 pm

Ok. Thank you.

I will give this a try.

I thought I did it that way, but I must have missed a step, or picked something out of sequence.

Mark.

Posts: 17
Joined: Mon Apr 03, 2017 2:33 am

Re: 1227165 Running 12P for a GM 2.5L Iron Duke with Turbo

Postby Mark_ZZ3 » Thu Jul 20, 2017 11:34 am

Well we are back at it ... time to get it up and running.

So here is what has changed. My son made up a nifty adapter to mount the TBI from a 4.3/5.7 engine on to the little old 2.5L. This will give us TWO injectors vs. the single one found on the 2.5L. The adapter plate is a simple 1.5" thick aluminum block with one 48mm hole (or so) on one side and twin 30-something on the other side, and a blend connecting them. Since this adapter is effectively a "restrictor" plate, no worries about the BIG TBI unit adding too much air. Self limiting.

So fast forward. It's mounted on the engine. All sensors connected. Cables attached. With some INJ flow tuning, I can get it to fire up and run, but it stalls almost right away. No amount of throttle will keep it going.

I figured it was too right or too lean ... tried setting the injector flow up and down. No luck.

Got it run with ONE injector connected. Hmm ... thought it was the fuel setting. Then we noticed if we connected the second injector up while it was running, the engine would die.

I tired the same thing with a spare injector (not connected to any fuel), and it does the same thing. I can feel it "clicking", but as soon as it is connected, the one that is running the engine drops down to a poor spray pattern.

It's like the computer can't run the TBI injectors? Is that the case?

I ran a dedicated 12V to the injectors. No luck. It's on the ECM side. I verified the wiring is correct. D15/D16. Doesn't matter which is connected or not, same result.

What should I have done to run TBI style injectors? Different driver to power them?

Mark.

Posts: 17
Joined: Mon Apr 03, 2017 2:33 am

Re: 1227165 Running 12P for a GM 2.5L Iron Duke with Turbo

Postby Mark_ZZ3 » Thu Jul 20, 2017 12:12 pm

hmm. So more testing. Runs fine with one injector plugged into D15 or D16. Either or, no matter. As soon as the second one is plugged in, the spray pattern goes bad and the engine stalls. You can feel the injectors clicking, but maybe not opening up completely or long enough. I tried to trick it by setting the flow rate way down. No luck.

I measured the resistance ... 3.5 ohms per injector. Seems ok with others I tested. Now the 165 computer can run a TBI with a single injector (stock 2.5L) or the TPI setup with banks of 4 injectors. The 4 injectors are each 15 ohm or so, so in parallel they are about 3 ohms. All seems fine.

I tried to run both TBI injectors from D16 (crazy idea). Same result.

Feels like the ECM can't power both. I've run dedicated +12.

I'm stumped.

More research.

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Joined: Mon Apr 03, 2017 2:33 am

Re: 1227165 Running 12P for a GM 2.5L Iron Duke with Turbo

Postby Mark_ZZ3 » Thu Jul 20, 2017 1:16 pm

Hmm. So some research. I'm using peak and hold injectors. Seems that they draw lots of current (hence peak and hold ... at a lower current). Only one injector per driver ... which is what I am seeing. Now the D15/D16 split should be two drivers, but they are not acting like that. Some suggestions are that D3 needs to be shorted to D9 in order to trigger the sense function for D15 to operate as a peak and hold. Wish I had a diagram to read instead of google.

Other options are to have an external driver for the injectors ... yuk.

More research.

Posts: 17
Joined: Mon Apr 03, 2017 2:33 am

Re: 1227165 Running 12P for a GM 2.5L Iron Duke with Turbo

Postby Mark_ZZ3 » Thu Jul 20, 2017 2:03 pm

Hilly Billy Garage ...

So the TBI injector is 2.5 ohms. The bank of injectors on a TPI is 4 X 15 ohm or about 3.75 ohms in parallel. Seeing as the injector driver can't handle the load of the TBI injectors, I tried some re-wiring to provide another ground. No change. It's late ... so one more change ... I added a 1 ohm resistor on the positive side of the injectors. TA DA ... they both fire now. Pattern is ok.

... and the engine finally rev's up nice. I wonder how well the heat will be with the 1 ohm resistor ... need to get one rated for a bit of amps.

I suspect I need to tweak my resistor setting to make it work (and last). Guess I'll be carrying around another '165 computer just in case.

Mark.

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