Jays2002vette

So i just put in a NOS system in my vette its a wet 125 shot with a plate the car only has an intake and new plugs so far besides the shot i mean i did only get the car a week ago so the first ran the car felt great till i got up to like a 100mph then the car sound like it was breaking up the rest of the way which was till 115 which was my trap it ran a 12.32 so i was like lets run in again i let the can sit for a little then ran again this time again at a 100mph it started to break up and then the check engine like started flashing i let off my trap this time was 113 and time was 12.34 so i drove the car off the track and then 2 seconds lata the light went off from what i understand the check engine light does that when it miss fires i have no idea what to do i need some help the car isn't tuned yet but i would def apprecaite some help thanks guys

-Jay

Beer99C5

iTrader: (21)

Did you disconnect any of the injectors wires to hide the noids? Guessing connector on one of the injectors is loose.

Happened with me on my install. Flashing Check engine light. Was the one injector wire we removed to put the purge noid under the fuel rail cover.

Double check the injector connections should be good to go.

Jays2002vette

i am not sure could be but it was jsut flashing when i was at like 100mph to 113mph then for like 15 seconds after then went off and has done it since and the system has been on it since sat and has not done it b4 either

Robert56

iTrader: (2)

Does it only do it when spraying? That'l really narrow things down. I suspect that's the case by looking at your times. I would not keep spraying untill figured out. Might be fual starvation, but just speculation at this point.
Robert

we_todd_did

iTrader: (97)

I would say its getting to much fuel, like your running out of bottle pressure.

Jays2002vette

yea it only happens when i am on the bottle but it only happens on the track like i know i shouldn't be spray but i actully just got home and i raced some supercharged mustang and i spanked him and there was no prob but i didn't break 100 though

Robert56

iTrader: (2)

Do you have a FPSS? If your fuel system is border line, you may be running out of fuel, or might be set to close and coming on/off?
Can you pull any codes?
Sounds like fuel cause you really have to be getting on it with the spray, meaning when you get to your heaviest demand on fuel, issue appears. A fuel pressure gauge could confirm or show ok.
What plugs and gap? To wide and might be blowing out, or heat range incorrect?
Robert

Beer99C5

iTrader: (21)

In my case it ran like crap at an idle, and you could tell something was wrong, if its fine and only top end, Look in the direction Robert is sending ya.

Z2K_MrJ

Try Lowering your shot?? see if it still dose the same thing..Your are spraying a wet shot so.. lets see if its a fuel Promblem..

Robert56

iTrader: (2)

Good idea, just might show something.
Robert

Jays2002vette

i sprayed a again today on the highway with the 125 the car moved out and felt good and no lights came on but it makes like a pinging sound i don't know hard to explain but its wierd also i but the car on the tech 2 and no hard codes came up only thing the came up was a os2 senor thing and a misfire but they were soft codes any ideas?

Beer99C5

iTrader: (21)

I am thinking you need to pull some timing...or lower your shot till you get a nitrous tune.

When I went over 100 I started to see KR and needed to pull a few degree's timing.

Are you running a stock tune or a custom tune?

Beer

Robert56

iTrader: (2)

At what speed and gear did you engauge the nitrous? Maybe some light lugging of the motor? or timing/fuel or? Best thing is as Beer suggested, get a nitrous tune for ultimate safety. Your $$ motor is worth the cost, and then no more speculating.
Robert

Jays2002vette

I am goin to TTP soon to get it tuned but i want to get the headers on there before i get it tuned i guess i am just to stay off the spray for 2 weeks or so till i can get the headers on and get in tuned ...and i sprayed at like 50ish mph not sure what gears its a auto

Robert56

iTrader: (2)

That's why I asked. I remember spraying my coupe/auto on the freeway in high gear crusing and pinging ensued. This was because I was lugging the motor (not good). Never spray in over drive when crusing, you just might burn a hole in the piston or something similar.
Robert

CAT3

iTrader: (9)

You can check plugs easy enough, I would have started there. With a flashing SES your misfiring, could be detonation as described in your "pinging" post, which at that point your removing minute particles of material from your pistons and depositing them on your plug, never a good thing. I would pull the plugs, inspect, and if there are signs of detonation start reducing timing, adding octane, or lowering shot size. Also would be very wise to monitor your fuel and nitrous pressure. Tuning sounds like a good start as well.

slow trap

iTrader: (22)

you said you changed plugs also,did you put in colder ones like the tr6s ?the pinging you are hearing is probably detonation,and at the top end your car won't be accelerating through the rpms as quick like in a lower gear so it's under more of a load.i'll say it's probably running alittle lean .definitely have it tuned before you spray again.

Jays2002vette

well i fixed the problem when i put the system in i switched the plugs and they were gapped right ...but i switch jus to a colder plug then stock instead of the autolite 103 so i was like lets pull the plugs so we did and they were messed up after just 10 days in the car and 1 bottle so we put in the 103's and the thing runs like a champ

SSmoky01

Good to see you have the problem solved before a piston took a ****.

Robert56

iTrader: (2)

Great, glad you figured it out. Now have some fun.
Robert