MattZ28

iTrader: (4)

Here is my setup:
'96 Z28
Bolt-ons
Strange 3.73s
3200 stall, CPT 4L60E
MSD Digital 6
MSD Digital Window Switch
NX GM EFI kit
NX GenX2 upgrade
Racetronix 255lph fuel pump
NGK TR6s @ .035
Bottle is mounted correctly (blowdown fitting direction is up, bottle is angled properly)
Shark Nozzle in stock IAT sensor location
MSD retarding timing 2 degrees (100 shot), activated by WOT switch


When spraying, it randomly shuts off....mostly in third gear. Actually, I'm pretty sure it's ONLY in third gear. My friend is also having this same problem with his car, but he is using a BMN window switch with the same N2O kit.

I was at the track Wednesday, and I sprayed in top of first, it sprayed all through second, then in third gear, it shut off, and then came back on before the traps...I gained 8mph in the 1/8th and 7mph in the 1/4 from a 100 shot because of this.

My window switch is set for 3000-5700.

Any idea what would cause it to shut off randomly like this? It only happens sometimes...bottle pressure is good and it happens when the bottle is full too....


*Edit - FYI I did not use the FPSS with the GenX2

Robert56

iTrader: (2)

Misadjusted FPSS?
Robert

MattZ28

iTrader: (4)

No FPSS..

2 Stroke Racer

iTrader: (11)

I would have guessed fpss also but since you dont have one, sounds like something with your window switch.

MattZ28

iTrader: (4)

Is it common for MSD Digital window switches to be defective?

Airwolf

iTrader: (2)

Check the connection for the MSD off the ECU. I used the tap supplied with the MSD unit and at high speeds it would loose contact. I ended up soldering the connection and have not has any problems since.
Hope this helps...

ITSTOCK

iTrader: (1)

It is, but that doesn't sound like your problem this time.

I would assume it is going through a relay, correct? If you don't have a relay in there, make sure you get one. With that said, check for a loose ground. If ALL grounds are good, check for any wire connections. The connections might be overheating causing a bad connection.

MattZ28

iTrader: (4)

I'm pretty sure the MSD is getting its signal from the Digital 6....it's been awhile.

And yes, it's through a relay. All grounds look good and connections seem nice and tight

MattZ28

iTrader: (4)

bump.

markp03

iTrader: (4)

i have the same problem!!! it happens with my msd digital window switch too!!!! almsot always in 3rd! i think it is my connection to the tach wire though...I would check that out before you test anything else

Qwick98Z

I have had problems also with the digital MSD. I have changed over to the old style box with the pills and it works like a champ.....

MattZ28

iTrader: (4)

FYI guys I got rid of the Digital MSD. Sent it back to Jeg's for a full refund, and got the analog MSD like ^^that guy did. Made 4 passes at the track last night and all is good

JRracing

iTrader: (35)

Glad to hear that. I am also glad I ran across this thread. i had the same problem the last time I used the juice. But it seemed like it came on then shut off pretty quickly.
I have no FPSS and I use the MSD window with the pills. I'm wondering if its a bad connection at the ecu. I know my ground is good, but something else is going on.

Luckly it happened when I tried it on the street and not the track. But I need to get this adressed before next season.

Its got to be a connection problem I think.

Robert56

iTrader: (2)

Us vette guys have that problem at the computer, a tiny wire to tap. If you don't use the pink/red snap connector, problems are often seen (using the blue connectors which are slightly to big).
Robert

oange ss

iTrader: (50)

wire taps seem like a good idea, but i dont use them or splices unless it's a life or death situation, for peace of mind and relability always solder electrical connections........i'm guessing wiring

Z-nos

Good thread I am glad I read that. I didn't know that the msd digital had that many common complaints..

Hocky

iTrader: (5)

I see the same problem and I also have a digital window switch... though I've constantly atrributed my issue to insufficient wiring.




haha