0411 Swap - 0 Degrees of advance?

[Richard_T]

So I just swapped an l-31/0411 pcm into my Trans Am and of course it won't start. Using a timing light I found the ignition timing was firing at 0 degrees TDC which explains why it doesn't want to start. Using the EFI live scan tool I confirmed that was no error the PCM is actually calling for 0 degrees of advance.

However, after looking through the tune file I see no reason for the PCM to call for 0 degrees of timing? According to the "Spark Timing When Cranking" table it should be calling for like 13 degrees of advance? I even tried changing the "Minimum Spark Advance", which according to EFI live's description is the absolute minimum timing that the PCM will ever allow, to 10 degrees and it's still calling for 0 degrees of timing?

The tune is essentially a stock 2002 l-31 express van tune with the exception of things like the VATS being disabled. I'm totally new to EFI live so I'm hoping I'm just overlooking something here. Any ideas as to what is going on?

[joecar]

Post tune/log files.

Are all the sensors connected and working...?

[Richard_T]

Yes all basic sensors are connected and seem to be working with one exception. When cranking the speedometer will read something like 20 mph when obviously that's not correct. Now since this is going into an older car there are a few items that are not being used. This is going into a car with a manual transmission so there is no range selector for the transmission. Items like the post cat O2 sensors, EGR, AIR, EVAP systems ect are also not in place. I was hoping to avoid something like this so I bought ALL new parts except for the PCM which is remaned. Thanks for your help.

[joecar]

Log file shows MAP sensor is pegged at 102 kPa during cranking... vacuum handpump on the MAP and see if it registers correctly on the scantool.

[joecar]

B0102 Cranking VE table looks wrong, this will cause a no-start.

B3701 Injector pulsewidth voltage adustment table is wrong.

Maybe a few other tables also.

[EagleMark]

DId you get the wiring spreadsheet from Lex Tech? He's got this dialed in.

[EagleMark]

Look at {B5915} Minimum Spark Advance. Stock is 10 degrees, in yours it's -15...

{B3701} Injector pulsewidth voltage and {B0102} Cranking VE table is same as stock cal... Joe must have compared to wrong cal...

[joecar]

Ah, yes, it's likely I compared to the wrong file, there are various 12212156 files.

I did see that B0102 has the same value in all cells, I didn't think that would work...

[EagleMark]

It may be your used to LS engines and this is a real Vortec, not a LS engine with Vortec badges? This is one of the .tun files used in the Vortec to 0411 swap.

[Richard_T]

So I had some time to work on the car a bit more this weekend and looked into some of the items you guys have mentioned.


MAP Sensor: It looks like when I was troubleshooting the ignition system I must have disconnected the vacuum line to the MAP sensor and forgot to hook it back up. I hooked the line back up and all looks fine now.

Speed Sensor: For now I just disconnected the speed sensor input to the PCM. I doubted that was the problem but surely an incorrect reading was not helping either.

Still no timing advance. I tried setting the minimum spark advance to 10. I tried setting the engine protection mode spark advance also to a minimum of 10 just in case. Still the PCM is calling for 0 degrees advance.

Is it possible my PCM is just shot? I mean with the minimum advance set to 10 degrees it should be set to no less than 10 degrees yet it’s totally unresponsive. Is there anything that will override that setting or am I misunderstanding what that table is all together?
Attached is my latest tune/log file which is again essentially the same thing but with the engine protection mode advanced to 10 degrees as well.


Again thanks for all your help. I’ve been tinkering with this car for about a year now and I would love to drive it again.

[Richard_T]

Look at {B5915} Minimum Spark Advance. Stock is 10 degrees, in yours it's -15...

Are you sure you don't have those reversed? I set the spark advance to 10 degrees and when I got the tune file the stock cal was -15 if I recall correctly?

[Richard_T]

DId you get the wiring spreadsheet from Lex Tech? He's got this dialed in.

Nope, I actually used the diagrams from a factory manual. It couldn't hurt to double check though. Is it posted somewhere?

[hog]

Nope, I actually used the diagrams from a factory manual. It couldn't hurt to double check though. Is it posted somewhere?
No you must contact Lextech and he will email the appropriate file to you.

peace
Hog

[onegonewild]

I am having the same issue with 0 degrees timing when cranking the engine over. Did you ever find a resolution to this issue?

[Daws222ooo]

I'm also having this issue, did you ever resolve it, if so how?

[onegonewild]

I have not. I do know that I am having a tough time getting the pesky P1336 with no luck. Am awaiting spring weather and use of a Tech II to try and resolve.

What combo is your engine? How far is your tuning coming along?

[Daws222ooo]

It's actually a ls1 6.0 turbo nitrous setup, I have a start up tune but it won't stay running long like 3 seconds. Most of the time while cranking I'm seeing 0 timing. I repined to a newer ecu. So I'm not sure of its in the tune or the wiring.

[onegonewild]

That sounds like an Anti-Theft issue.

[Daws222ooo]

Maybe but vats is off. Is there something else tied into the anti theft?

[onegonewild]

Does anyone know what the resolution was to Richard_T's issue?