Tiger2o69

iTrader: (16)

Just installed nitrous and have ran a 75 shot fine for a while....

I just put in a 100 shot and when I run it and let off it starts popping, Its not very loud but its there. It may be popping durint wot but I may not be able to hear it.

Anyway I logged this w/ hp tuners and it doesnt look good to me....

I punched it in 2nd and after I stopped spinning I hit the nitrous and im guessing that where I went really lean. But my thoughts it my motor would have blown if it really went this low.

My non nitrous WOT numbers are like 930-940's....

When I searched I found that popping could be from

1. blown out plugs (mine are gapped at about .38)
2. rich popping
3. lean popping

GM Muscle

iTrader: (9)

If your non nitrous numbers .930-.940 what do your nitrous run O2s look like? Is it just happening after the run and not during the run? My car will pop on decel after every run. For me it's a rich condition right when I come off the bottle, if I snap the throttle acouple of times after the run it won't do it.

As for hurting the motor, I've seen the O2s drop to .050mv with a dead fuel noid and it hurt nothing. So it is possible to go super lean and still have the motor act normal.

Tiger2o69

iTrader: (16)

I was trying to post up the hp tuners log but it was too much. Ill cut it down and post....I believe its only on decel but not sure....

GM Muscle

iTrader: (9)

Can you give us an idea of what your averages where on the spray only. I think you need the HPT software to view any logs. Normally pulling fuel off the stock rails, as soon as you hit the nitrous you should see a quick and sharp lean spike, then things should richen up and smooth out. How long where you actually spraying?

Tiger2o69

iTrader: (16)

Only spraying from about 50 to about 110......It actually did exackly what you said. Maybe it is nothing but i want to be on the safe side....Do you have excel? I can post it in that.

GM Muscle

iTrader: (9)

I don't see excel under my programs list but who knows, I have so much **** on this computer I find new things all the time. I supose I can try and download it to see if it will automaticly pull up the program and open it.

It's not great to tune with your O2's but after that lean spike things should settle down at anywhere between .940-980 (that's about where my car runs when the A/F ratio is in the low 11s). If you get some extra cash pick up an LM-1 wideband or something similar. That little tool has been a life saver for me.

GHOSTRACER

iTrader: (1)

If you are getting out of the gas at the end and you are in D, you'll get popping, at least mine will. I will usually just put in in OD at the end and I dont get any popping.

Tiger2o69

iTrader: (16)

Hmmmm that weird... I do have it in OD however. I figured out a way to let u guys looks at the logs. Hopefully its nothing but this logs looks bad to me...

Tiger2o69

iTrader: (16)

Tiger2o69

iTrader: (16)

Tiger2o69

iTrader: (16)

Tiger2o69

iTrader: (16)

Those 1st 3 are actually what happened......They one above is the average of the histogram..

Tiger2o69

iTrader: (16)

The histogram is what worried me when i seen those 500 avgs I was like ........

However it looks like waht gm muscle said.....It went really lean (in the 60's on one 02 and 100's on the other) Then it looks like it went up thru the 800's then into the 900's

Is this what's suppose to happen?

If a lean and rich condition isnt the problem causing the popping could it be .38 is not cold enough for a 100 tnt shot?

GM Muscle

iTrader: (9)

At what number did you hit the nitrous and at what number did you let off. I think that lean spot is way to lean for to long, it looks like it lasts throught the whole gear. I would get that car on a wideband and see what's going on. Are you still on the stock fuel pump? I would also give the fuel noid a quick check to see if it's sticking.

If this helps I pulled out one of my LM-1 runs. This was a really rich 200 shot but you can still see how quick and sharp the lean spike is. You can also see how the A/F ratio leans out a bit then drops off when I let off.

Tiger2o69

iTrader: (16)

I hit the nitrous around the low 50mph range I believe.....A LOT of weird stuff is going on ....Looks like I was at 80mph then dropped to low 70s but it definetly didnt feel that way......Also the rpms look funny in that first pic.... I stopped spraying right at 112 so it looks like it finally got rich...My 02's sensors are always having problems...I am going to dyno feb 5 w/ a wideband...

So far I have sprayed the 100 shot 4 times and it always made the popping noise but nothing bad has happened yet that i know of....

Wouldnt there be all kinds of knock if something bad was happening??

Would you think it would be safe to go run another run starting the nitrous when I know exackly where and see what happens or do you think i should just wait to the wideband.....

Also can I check my solenoids by unhooking the lines from the solenoids and looking to see if gas/nitrous come out???

A quick touch lol?

They both click at the same time so its hard to hear if its both or one I suppose I could unhook the ground them but the wires are crimped together


yes still stock fuel pump but shouldnt it be able to handle a 100 tnt shot??? I dont know what its putting to the wheels but it picked my up from 12.5@ 114 to 11.5@ 125.5 spraying through the gears...1.90 60'

GM Muscle

iTrader: (9)

When my fuel solenoid failed and the O2s dropped into the .050 range there was no KR at all. The only thing that was a give away was that the car kind of felt "flat" and it wasn't making any torque at all. I wouldn't hurt to wait for your dyno but you could try it again. When tuning I usually do my runs from the bottom of 2nd until the top of second. When your O2 first dived in to the low .100s was that when you hit the nitrous.

As for the funny rpm and mph. That could be do to slight surging from rich or lean conditions created by a number of things. Usually low bottle pressure, not purging and fuel leaks or unstabel fuel pressure are pretty common causes.

To check you fuel noid, unhook the main N20 feed just to make sure no nitrous is the line. Then bypass you window switch and unhook the fuel lines at the nozzle and put them in a coke bottle or something. With the car running just bump the WOT with your fingers a few times. Also check for any leaks at any fittings, I've had that cause an unstable A/F ratio too. What I do is put some convoluted tubing around all the connections, go do a run, then check the tubing for any fuel.

Stock pump should handle a TNT 100 shot but it could be a culprit if you have a fuel problem. You will probrably also see a bigger lean spike wiht the stock pump.

Tiger2o69

iTrader: (16)

Thanks, I really appreciate the time you spend helping. Ill try what you said and hopefully figure out whats going on....Maybe Ill step down to a 75 shot and run that and see what happens...Everything seemed to be good however last time....If nothing goes wrong there I may try the 100 shot again

GM Muscle

iTrader: (9)

Not a problem. I've spent a good amount of time pulling my hair out over nitrous issues so I know how it can be frustrating.

Tiger2o69

iTrader: (16)

I checked the fuel noid and fuel cam out ( a lot) but my car acted funny....So I held my finger on the switch for a second and the car died....I started it up again and it did the same....I recorded it on hptuners but havent looked yet because i was going to the track...Didnt run n2o but did run a best ever n/a run....

Since there was no jets in the gas line it was probably flowing out much much more like a 200 shot so is this normal. Im guessing it took all the fuel away from the injectors.

SDB

iTrader: (7)

Try this first....when using the nitrous, go WOT, then activate the nitrous system, then BEFORE letting off the gas, disarm the nitrous system and THEN left your foot from the go-fast pedal. This solved my popping problem.. Essentially too much unused fuel in line getting flooded as nitrous is used up at the end of a WOT run. Try this first to see if it doesn't solve the popping after running.