Start, wont run problem

[quick72toy]

Ok It has been a while since I have had to trouble shoot, and am having a problem fixing this. Out of the blue, the car will start and run for 2 seconds but dies.
 I first thought it was the anti theft, and re-did the sequence, but it still behaves the same.
I then disconnected the battery for a few minutes, and tried again. Same result.
Put battery on charger to make sure battery voltage is up. No change.
Pulled WB O2 sensor, checked, and free air recalibrated. No difference.
I then thought it might be a loose park/ drive indicator wire that may have prevented the anti-theft, and pulled the console and checked from sw to ECM pin .It is okay.
Ok, thought it might be the cam sensor. checked and reset sensor with Caspers tool. No change.
Fuel pump is working fine and pressure is good.

Running Modded ECM, 52 lb Siemens injectors,  MAFTpro, Bob's Extender chip, WB O2 Sensor. Running in Speed Density mode.


Help! 

[Steve Wood]

what's the battery voltage and what is it reading when you are cranking the car?

[motorhead]

What is the wb showing? Assuming it can even register a reading.  Mine goes really lean at idle 16-20+  AFR and needs a fair bit of Afterstart Enrichment to hold an idle until Part Throttle Tracking takes over.

[quick72toy]

Steve
I've got it on a charger when I'm cranking it over, but I'll measure the voltage next time i try to start it.

Mike
Not enough time to register anything.

Cant get the Power logger to work ~!@# So I'm going to pull it out, and hook up Direct Scan to see if I can get any readings.

[Steve Wood]

Pull Pl off and see if it will run

Steve

[quick72toy]

Pulled the PL and hooked up DS. Recorded a key on engine off, and a start/ run/stall file. Too tired to post them tonight will post later tomorrow.

[quick72toy]

Fixed it! 
I noticed in the DS file that my voltage dropped/dipped when starting, and remember thinking maybe the battery was low on charge, but I had it on a charger, and used the charger to start the car, so... I had a look at the battery cable lug on the solenoid, and saw that the nut was slightly loose. Tightened it up, and car cranked much faster. Reset the ant-itheft and bingo! Car started and ran fine. I guess there was enough of a voltage dip during cranking to trigger the anti-theft in the chip.

Thanks David Justa6 for lending me your spare ECM and chip for test purposes.

Paul

[daveismissing]

Good News! You had it from the start!
If it was in a Buick a clue would have been the clock resetting when cranking...

[Just a Six?]

Fixed it! 
I noticed in the DS file that my voltage dropped/dipped when starting, and remember thinking maybe the battery was low on charge, but I had it on a charger, and used the charger to start the car, so... I had a look at the battery cable lug on the solenoid, and saw that the nut was slightly loose. Tightened it up, and car cranked much faster. Reset the ant-itheft and bingo! Car started and ran fine. I guess there was enough of a voltage dip during cranking to trigger the anti-theft in the chip.

Thanks David Justa6 for lending me your spare ECM and chip for test purposes.

Paul

Well my parts didn't help but sometimes just sitting & talking about it gives you good ideas. 
Altho Steve nailed it right away with his cranking voltage test. 

[quick72toy]

Yeah Dang hybrid  LOL
Yeah, I needed the break David. Sometimes it's just good to just chew the fat, and forget about it for a bit.
Thanks Steve you were bang on as usual 

Cheers,
Paul

[earlbrown]

Fixed it! 
 
 I guess there was enough of a voltage dip during cranking to trigger the anti-theft in the chip.


Paul

And it's AMAZING just how little it takes to reset the anti-theft.   I was ready to burn my car to the ground (and my house around it) a few months ago over that stupid feature

[Steve Wood]

that is the reason I don't use antitheft chips

[Just a Six?]

that is the reason I don't use antitheft chips

Me too! Never had it & never will! Lots of threads around about it causing issues.