Disable VATS, no injector pulse. has spark. LS3

[jamesdt]

Hey guys. I currenty have an ls3 crate engine which has a cam only, 237/248 @ .612" lift. I have done a conversion into a car using a turbo 400 transmission.

The e38 ecu im using is from a manual 2010 model vehicle #12633238

the os is 1250230

I have disabled VATS 1 & 2, disabled the starter checks, under the systems tab i have disabled the starter diag and the clutch interlock.

Is there anything else im missing here? the engine has spark but no injector pulse. With the ignition on there is 12v at the injector.

Really need to get this thing started.

Attached is the current tune if any one could help out.

Thanks.

[witchertorque]

had the same problem belive it or not in a 68 camaro LS swap with a e78 here comes the belive it or not i disconnected the battery for 15 minutes hooked up back again problem solved

looks like needed hard reset jajajajaja

[jamesdt]

i wish disconnecting the battery would help but still no go.

I logged the pid fuel cut type and it says none,
during cranking i can see the crank sensor counts
throttle position says 28% when im not even touching the throttle but and only goes to 84% when my foot is fully pressed.
cranking speed is around 120rpm
also during cranking the INJ. pulse width avg for bank 1 and 2 is around 2.2ms

does everything sound about normal?

Thanks again

[EDH]

I don't have a full answer to what is happening but 84% is a normal full throttle reading and the 28% is probably normal for dbw cranking throttle position. 2.2ms should be enough fuel to crank. When you say you have no fuel, do you mean the injector never pulses or that you have a dry spark plug? Have you put a test light on one of the injector connectors to check for ecu signal? Does 120 rpm cranking speed seem low.....

[MikeOD]

Did you do a "Write Entire" after picking all the disable vats stuff? If you only write the calibration that first time, it won't work.

[jamesdt]

i have a noid light fitted to the injector which has no pulse during cranking.

Yes write entire

[01 MidMet WS6]

Does it crank at 2.2ms consistently or is it moving around some. That seems low for a stock LS3 injector on a cold motor. I am sure you have but need to ask, did you check codes?

[jamesdt]

im thinking there is an issue with the map sensor.

for some reason its only reading 16kpa with the engine not running. During cranking stage it remains the same at 16kpa.

the map sensor values are 128.13kpa and the offset value is -0.31kpa.

i changed the map sensor valves to what the vcm enhanced 2 bar map speed density would have read which was 200.00kpa and an offset value with 10.34kpa.

Doing this i was able to see injector pulse also injector pulse width jumped to around 10.5 ms on the first crank then dropped to ~4.7ms during the rest of the cranking

So engine has spark, injector pulse is there but something is still not right.


now i had a look at another one of my vehicles which has l76 6.0l gen 4, with the engine not running the map sensor reads 102kpa, during cranking you can see is decreasing as the engine starts to pull a vacuum.

the map sensor fitted to the ls3 is #55573248. what are the correct sensor values for this?

The person who modded my harness to suit had to change the map sensor pigtail as the gen 4 engine it was removed from had a different map plug to the ls3 engine.

Thanks for the input so far. Also please view the tune again. As the one i first posted was incorrect.

[jamesdt]

attached is a photo of how the map sensor has been wired in. Is this correct?

Thanks

[EDH]

So, the ecu is reporting the normal injector pw values but you still have no injector noid light activity.

[Jon S.]

attached is a photo of how the map sensor has been wired in. Is this correct?

Thanks

The light green wire (MAP signal) and orange / black wire (MAP ground / low reference) appear to have been transposed (in the wrong connector cavity). Try switching these two wires and see if that corrects the MAP issue.

[jamesdt]

after some reading, the ls3 map sensor should be wired as

Pin 1 - C = Grey, +5v
Pin 2 - A = Org/Blk, Ground
Pin 3 - B = Light green, signal


so from left to right green, org/blk, grey.

Not grey, green, org/blk as its currently wired. Ill change the wiring when i get home and see what happens.

[jamesdt]

good news. Got it fired up. Map sensor was wired incorrectly. I wired it as per my above post and the map now reads a more realistic value and started straight away.

Now the scanner reads 169kpa with the engine not running. shouldn't this read closer to 128.13kpa as per the linear settings?

Because its reading higher than it should its running fairly rich..

I'm guessing i will have to play around with the offset value so the scanner reads a more realistic atmospheric pressure with the engine not running?

[MikeOD]

shouldn't this read closer to 128.13kpa as per the linear settings?

No, it should not read 128 KPA...that's way too high for engine not running. The stock LS3 MAP sensor is 128.13 and -0.31, and at key on engine off, it should read atmospheric pressure (close to 100KPA depending on your altitude and the weather that day).

[jamesdt]

Ok,

with the scanner pluged in to my L76 vechine, the map reads 102kpa with the engine not running, the map sensor linear for that E38 ecu is 94.34 with offset of 10.34 but this has a delphi style map sensor.

If my LS3 is reading 169kps with the engine not running, what do i have to do to get it down to ~102kpa with the engine not running?or is the sensor damaged from not being wired up correctly the first time?

Thanks again

[jamesdt]

Got it running heaps better, to get the map to read 100kpa with the engine not running I had to adjust the offset to -3.31 instead of -0.31

Is this common? Why would did I have to adjust the offset from the factory values?

Cheers

[01 MidMet WS6]

Got it running heaps better, to get the map to read 100kpa with the engine not running I had to adjust the offset to -3.31 instead of -0.31

Is this common? Why would did I have to adjust the offset from the factory values?

Cheers

You should not have to adjust the value, what was it reading with -.31? What is your elevation?