LS motor start problem

[nismoautoxr]

This engine is fresh but the car has been squirted for several years. the engine is a 6.0 aluminum LS2 block with a 24x stroker crank . it is using the LS2 front cover with an LS2 cam sensor . its using a cam gear that has the trigger on it. previously the engine had an LS1 cam sensor that triggered off the rear of the cam. It ran fine . I tried to start it up and it just sputters like its only hitting on a couple cylinders. I'm still using the LS1 ignition decoder. I was not able to establish comms with it last night to pull a composite log for some reason.....this project has been dormant for about 6 months and I'm just picking it back up. has anyone been down this road using a 24x crank and LS2 block which usually would have had a 58x crank but I believe in 06 the GTO used the 24x in the 6.0 . not positive but the timing set was listed for a 6.0 with a 24x crank?

[nathaninwa]

Can you pull the sensor and see if it's the half moon cam gear or the 4 tooth cam gear? Try starting it again in wasted spark and fuel mode to see if it will fire

[nismoautoxr]

Im pretty sure I remember it being the half moon but when I get home and get comms established Ill find out. I had it set up for BT adapter but.thats in my miata. I just gotta get the serial setup so I can see whats up. Im also trying to get oil pressure too so its maki g me a little nervous because I assembled it several months ago and the pump isnt wanting to act right. Ill try wasted too.

[jsmcortina]

24X crank and 4X cam is not currently supported.

James

[nismoautoxr]

It starts and runs on wasted cop so the cam trigver has to be the issue.

[nismoautoxr]

24X crank and 4X cam is not currently supported.

James

So what would it take to get it to work?

[jsmcortina]

24X crank and 4X cam is not currently supported.
James

So what would it take to get it to work?

Possibly a new wheel decoder.

James

[nismoautoxr]

Im not even sure its a 4x gear. I have an issue right now where I dont think the oil pressure is right so untill I sort that...its kindof moot. Im gonna log a csv and see what the cam sensor is seeing.

[nismoautoxr]

here is the csv...it looks to me like either the pot needs to be fiddled with for the cam trigger or the sensor is just not working. it triggered once on key on but after that the cam is out to lunch. that is with the ignition decoder set to log crank and cam like I did with the miata today.

[jsmcortina]

Not sure if this helps, but remember that the LS1 and LS2 sensors use different wiring, voltages and pullup. In the manual.

James

[nismoautoxr]

Not sure if this helps, but remember that the LS1 and LS2 sensors use different wiring, voltages and pullup. In the manual.

James

Yes that occured to me last night. The crank sensor is still the LS1 but I forgot that the cam sensor is electrically differant. That is likely the culprit.

[nismoautoxr]

so in the process of finding and repairing the no oil pressure issue, I verified the cam sprocket has a half moon trigger on its face for the cam sensor. Does this mean that the LS1 decoder is going to work for sequential and cop ? Previously it used the black 12volt hall sensors for the 24x LS1 cam and crank. The ms manual says that they have built in pullups . Reading in the manual the grey sensor for the cam needs a pullup and 5 volt power source. Does this mean that I need to install the pullup on the MS3x board and change the power source on my sensor from 12 to 5 or would it be just as well to just do a harness pullup in the engine compartment? Just looking for some opinions on the pros and cons. I would have to acquire a pullup for the 3x if I went that route.

[nismoautoxr]

what size pullup is recommended ? 470? 1k?

[nathaninwa]

I did 1k pull-ups off the 5 volt feed for the tps and map sensor in the harness near the sensor. I'm sure it could be done inside if you wanted. Also the pinout is different than the LS1 sensor

Since it's half moon, the LS1 decoder will work fine

[nismoautoxr]

thanks man. I hit the easy button and I tapped into the TPS 5 volt and I put a 1k pullup in the harness going to the cam sensor and it works just fine. I'm sure I could have added JP? on the x board and it probably would have worked but I didn't have a pullup for that .