Car quits at 1/2 track

[N2BUICK]

Posting in this forum because I have a Fast XFI system. Not sure gremlins are Fast related?/
Problem is car runs and drives great off the track, but at times on the drag strip the car will "nose over" badly at 1/2 track. Car does not die, data logging is lost, check engine light comes on. Try full throttle again, car stalls
badly.
At our Ford/Buick shoot out this weekend on the final pass they said it popped real loud when it nosed over.
We thought it was fixed Saturday AM when we ran a ground wire from the battery top terminal to the intake. Thinking was the top post was having and internal problem. My top post powers the Fast system.
Made a pass after adding this ground, car ran great. Final pass in elimination its back to it loosing power.
I am adding some data logs, they are brief and weird. The logs on all of the sensors look like "saw teeth"
These saw teeth logs showed up on some logs weeks ago when I was dealing with a dying/ dead 3 BAR map
The volts show 15+ is this an issue to the Fast?
Added note Friday night while in the staging lanes, starting and stopping the car at one point I tried to start the car and just cranked, Fast said ECU could not be found. Panicked, tried to start again, all was fine ?
Looking for ideas.
Big thanks to E Ticket for his help at the race.

 

[pacecarta]

how about a little info on your combo
fuel used etc
looks like a race gas tune (25deg timing 11.5 AF target) but i dont know what you have in the tank

your logs lack esc (knock) , add that to your log dash
i don't see any spark being retarded but depending on the firmware version of your xfi it may not pull timing with kr . if you aren't on 2.0 see sticky http://turbobuick.com/forums/threads/important-esc-retard.330397/

your fuel pressure sensor is either off or your base fuel is set incorrectly (looks like 37 psi base --0psi) it should be 43-45 psi with line off

your log getting cutoff looks like you have the max log setting set for 30 seconds and you timed out in middle of pass .
goto logging >setup real time logging and increase the max log time

the breakup and pop could be ignition related... bad coil , bad wires ,bad plugs , loose wobbly balancer /crank trigger
have the ignition tested when its hot , test the wires and check the plugs , check the balancer

 

[TurboDave]

I'm not an XFI guy, and can't look at your logs, but...... And this may be a stretch; but I suffered a problem that sounds VERY much like yours. many years ago.

I doubt this is your issue, but look real close at where your positive battery cable heads down toward the starter, and passes under the passenger side header. Look for any evidence that the engine could be torquing over and touching the positive cable (grounding out your entire electrical system).

 

[N2BUICK]

how about a little info on your combo
fuel used etc
looks like a race gas tune (25deg timing 11.5 AF target) but i dont know what you have in the tank

your logs lack esc (knock) , add that to your log dash
i don't see any spark being retarded but depending on the firmware version of your xfi it may not pull timing with kr . if you aren't on 2.0 see sticky http://turbobuick.com/forums/threads/important-esc-retard.330397/

your fuel pressure sensor is either off or your base fuel is set incorrectly (looks like 37 psi base --0psi) it should be 43-45 psi with line off

your log getting cutoff looks like you have the max log setting set for 30 seconds and you timed out in middle of pass .
goto logging >setup real time logging and increase the max log time

the breakup and pop could be ignition related... bad coil , bad wires ,bad plugs , loose wobbly balancer /crank trigger
have the ignition tested when its hot , test the wires and check the plugs , check the balancer

 

[N2BUICK]

The car has c16 in it for the race. I will add the knock to the dash. Fuel pressure is on the low side I can crank that up.
The logs are cutting off at half track because I am loosening connection. The logging on the at least on the last pass was set to trigger on 50% TPS. 30 sec should be enough?
I am sure I have the latest firmware.
The car never pops or breaks up. It only was heard to pop once Saturday at half track. Not saying the ignition is not at fault, at this time all is in question.
To Turbo Dave's comment the positive cable is high on the list to look at. With these HR Parts motor mounts the engine does not seem like it would be torqueing over, especially at half track?
Thanks for the input.

 

[pacecarta]

30 seconds apparently isnt enough
the "friday" log was definitely clipped from the 30 second max log limit . you didnt leave the tree until until 27.40 seconds into the log you may have started the trigger snapping your wheels in the water or in the burnout or waiting for the track to be clear or wiped down

i use the spacebar to start my logs and dont hit it until my opponnent and i are ready to roll into the beams

 

[krom]

I'm not an XFI guy, and can't look at your logs, but...... And this may be a stretch; but I suffered a problem that sounds VERY much like yours. many years ago.

I doubt this is your issue, but look real close at where your positive battery cable heads down toward the starter, and passes under the passenger side header. Look for any evidence that the engine could be torquing over and touching the positive cable (grounding out your entire electrical system).

I have had this same problem.

 

[RIFF RAFF]

I have had this same problem.

SO DID HELLOBOZOS

 

[kidglok]

SO DID HELLOBOZOS

But his was because of the stock ECM


Posted from the TurboBuick.Com mobile app

 

[RIFF RAFF]

But his was because of the stock ECM


Posted from the TurboBuick.Com mobile app

THEN HE SWITCHED TO XFI . AND HAD THE SAME PROBLEM .. I THINK . BUT I DONT WANT TO GO BACK AND READ THAT CRAP AGAIN .

 

[N2BUICK]

Yes my logs were hosed up early on, changed them latter. I also went to triggering the logging as I pulled into to beams.
Check Engine light, coming on when car quits, the only error code in the Fast log was Wide band fault.
Anyone know what the difference of a blinking Check Engine light and just a steading on lamp? When I was in the staging lanes the car ECU could not be found by the Fast, Check engine lamp was blinking. Cranks good just would not fire. 5 minutes later what ever was wrong went away, car started like normal.

 

[HighPSI]

Your having a voltage/ground issue. The flashing SES light is because the voltage is dropping below 9 volts when cranking and putting the XFI in "Flash" mode. You have to turn the key off, to reset this, otherwise it will never start. You may want to install a relay and hotwire the XFI. I didn't look at the logs, but if they are shutting down mid run, the ecu is probably resetting.

 

[N2BUICK]

Your having a voltage/ground issue. The flashing SES light is because the voltage is dropping below 9 volts when cranking and putting the XFI in "Flash" mode. You have to turn the key off, to reset this, otherwise it will never start. You may want to install a relay and hotwire the XFI. I didn't look at the logs, but if they are shutting down mid run, the ecu is probably resetting.

Cal
Thanks for the input. I will try and get a word with you one day at Bowling Green. See you there.

 

[HighPSI]

We have four tents set up and I try not to venture to far away from them. Stop by and we can try and figure out what the issue is

Posted from the TurboBuick.Com mobile app

 

[Eticket]

There is no fuel pressure issue. Please, do not touch your fuel pressure regulator.

Check your power and ground wiring as Cal has said. Also, even swap batteries to see what happens. I have a dual terminal battery in my pickup truck right now in which the side ground terminal does not work and the top does. This can be your problem vice- versa.

 

[N2BUICK]

There is no fuel pressure issue. Please, do not touch your fuel pressure regulator.

Check your power and ground wiring as Cal has said. Also, even swap batteries to see what happens. I have a dual terminal battery in my pickup truck right now in which the side ground terminal does not work and the top does. This can be your problem vice- versa.

John
Why didn't you raise the battery idea at the shoot out !!! I would have pulled the battery out of my truck and tried it.
I will not mess with the FP reg.

 

[Eticket]

Your log doesn't show a voltage issue but I wasn't thinking about how the battery could have shorted.

 

[Eticket]

Austin, I sent you a PM