Autotap not working & Nitrous problems...Getting Frustrated

[01 RT SNAKE]

Sorry this is kind of long.

Well my nitrous install will never be complete if I can't sort out the bugs. I armed the FJO progressive nitrous controller and went for a ride with the bottle empty. I wanted to make sure that the gas solenoid is doing it's job and triggering at my desired rpm point. I was told that the car will basically bog down due to the rich state letting me know that the solenoid is opening.

I nailed it, blew a fuse when the FJO triggered the gas and nitrous solenoids and the car started running like crap. It smells like gas. I checked to make sure that the solenoid wasn't stuck open by removing the gas lines from the throttle bottle tubes and starting the car. There's no gas being sprayed in there. Next, I checked to make sure I didn't blow any stock fuses. I didn't. I then changed the spark plugs thinking that I possibly fouled them with too much gas. They were fine.

The fuse that blew is inline from the positive post to the arming switch for the solenoids. It's a 15 amp fuse. FJO's wiring diagram shows a 5 amp fuse for this application. I have a 40 amp fuse inline from the positive post to the nitrous relay as per NX's instruction manual. I'm guessing these are reversed because I was told by NX that their Nitrous solenoid draws 28 amps and their gas solenoid draws 4-5 amps. This would obviously cause the 15 amp fuse to blow.

Next, I completely disconnected the FJO box and the car was still running funny. Hesitating when I gave it gas in neutral. I have an Autotap diagnostic tool and tried hooking it up to the OBDII port. It will not read the VIN and says it's not connected. I hooked it up to the Chevy Cavalier and it worked just fine. So it's definitely the OBDII port on the Viper that is being stubborn. What could be causing it to not be recognized by the Autotap? I tried re-plugging it in a thousand times, pushed on the wires on the back of the OBDII port and still nothing.

I crawled under the car and checked all the wiring. Nothing looks out of place.

The little catalytic converter check engine light is on. It went off momentarily and then I hooked the FJO wires back up. It came back on. I've been driving around for two weeks with this thing hooked up and I haven't had a single problem. Now today when I arm it, all Hell breaks loose.

I took the car back out for a test drive and it's not hesitating anymore or having the strong gas smell, however, it's popping just a tiny bit close to redline on the 1-2 shift. Does this sound like an O2 sensor problem?

I'm starting to get tired of this install. Please lend any suggestions you might have.

Thanks,

Mike
2001 RT/10

 

[RTTTTed]

Seriously, every first time instal is a learning process, it gets easier each time you do an instal.
You said you changed your plugs, they were fine. Did you put them back in? You may want to use a push button to activate your Nitrous until you have it working, then start the FJO stuff. Try a different OBDII code reader and see if it works. The engine must be running perfect before using the Nitrous otherwise there may be blown headgaskets, burned pistons, etc. If you get too frustrated ... you can always pay someone to do the job.

Ted

 

[viperrt96]

You didn't say what shot you had in it but it will flood your car especially if you only let the fuel solenoids come on. You can test the FJO with the car not running. I run the FJO and have no problems with it. I wouldn't use anything else. So I'm going to go thru a few things you said.

You said "The fuse that blew is inline from the positive post to the arming switch for the solenoids. It's a 15 amp fuse. FJO's wiring diagram shows a 5 amp fuse for this application. I have a 40 amp fuse inline from the positive post to the nitrous relay as per NX's instruction manual"

I know it's hard to explain what you've wired thru description so I'll ask a few basic questions"

How and where are you activitating (arming your system) the FJO?

The power source (what you will be arming it from inside your car) should go only to the input wire ((Slot A) or the white wire on the FJO) and the (87) side of the relay that is the power source to your NX solenoids. Looking at your relay (power source for the NX solenoids) the (30) should be the direct wire to your battery. 87 should be the side that goes to the solenoids. 85 goes to your FPSS(fuel pressure safety switch) and if you are not running one it needs to be grounded. If you are running a FPSS make sure it's not close to any of your NX solenoids as the interference from the coils will mess with it.

How are you signaling the FJO?

The white/red (slot B) wire should be your TPS signal.
The red wire (slot C) is not used
The green (slot D) wire should go to your tach signal. *This one is important

Please use the tach signal and not a coil driver. Unlike the Raptor shift light the FJO can pick up the Vipers Tach signal just make sure your RPM multiplier is set at (divide by 2.5)
I'll get to programing later after you verify your wiring

The FJO Controller gound (slot K-black) and Driver ground (12 AWG black) both should go obviously to a good ground

Then Finally the Blue (stage 1) from the FJO should go to the other side of your NX solenoids. Red (stage 2) not used.

So your NX solenoid wires (2 each) should only go to the power side of your relay (87) and the blue (12 AWG) stage 1 wire from the FJO.

And you can test your FJO without the car running. I would depressurize your fuel line. NOS empty. Key on engine off. Arming on and flip your TPS and you will hear the solenoids click.

 

[Jack B]

Sorry this is kind of long.

Well my nitrous install will never be complete if I can't sort out the bugs. I armed the FJO progressive nitrous controller and went for a ride with the bottle empty. I wanted to make sure that the gas solenoid is doing it's job and triggering at my desired rpm point. I was told that the car will basically bog down due to the rich state letting me know that the solenoid is opening.

I nailed it, blew a fuse when the FJO triggered the gas and nitrous solenoids and the car started running like crap. It smells like gas. I checked to make sure that the solenoid wasn't stuck open by removing the gas lines from the throttle bottle tubes and starting the car. There's no gas being sprayed in there. Next, I checked to make sure I didn't blow any stock fuses. I didn't. I then changed the spark plugs thinking that I possibly fouled them with too much gas. They were fine.

A couple of points:

The AutoTap tool at one time didn't support DC pcm's. I could not get it to work on my 97, I ended up going with the EASE unit from Roe.

Trying to use a five amp fuse when you are pulsing the solenoind is not going to work for long. Different solenoids pull diffrerent currents, especially when pulsing. Pulsing solenoids also can lead to premature failure. There is not domestic manufacturer that guarantees their soleninoid when pulsing if there is not another solenoid in series for safety reasons.

When you say the CEL was on, you cannot guarantee that it was a cat code, you need you scanner working. I have been running nitrous since 2000 and have learned you need to monitor both a/f and fuel pressure, if you don't you are guessing and looking for trouble.

The fuse that blew is inline from the positive post to the arming switch for the solenoids. It's a 15 amp fuse. FJO's wiring diagram shows a 5 amp fuse for this application. I have a 40 amp fuse inline from the positive post to the nitrous relay as per NX's instruction manual. I'm guessing these are reversed because I was told by NX that their Nitrous solenoid draws 28 amps and their gas solenoid draws 4-5 amps. This would obviously cause the 15 amp fuse to blow.

Next, I completely disconnected the FJO box and the car was still running funny. Hesitating when I gave it gas in neutral. I have an Autotap diagnostic tool and tried hooking it up to the OBDII port. It will not read the VIN and says it's not connected. I hooked it up to the Chevy Cavalier and it worked just fine. So it's definitely the OBDII port on the Viper that is being stubborn. What could be causing it to not be recognized by the Autotap? I tried re-plugging it in a thousand times, pushed on the wires on the back of the OBDII port and still nothing.

I crawled under the car and checked all the wiring. Nothing looks out of place.

The little catalytic converter check engine light is on. It went off momentarily and then I hooked the FJO wires back up. It came back on. I've been driving around for two weeks with this thing hooked up and I haven't had a single problem. Now today when I arm it, all Hell breaks loose.

I took the car back out for a test drive and it's not hesitating anymore or having the strong gas smell, however, it's popping just a tiny bit close to redline on the 1-2 shift. Does this sound like an O2 sensor problem?

I'm starting to get tired of this install. Please lend any suggestions you might have.

Thanks,

Mike
2001 RT/10

A couple of points:

1. You cannot guarantee that it was a cat code, you need your scanner.

2. A 5 amp fuse won't work when you are pulsing, the effective (rms) current drastically increases. Another thing to think about, many a solenoid has failed when pulsing. No US manufacturer will guarantee their solenoid while pulsing without installing a safety solenoid in series.

3. I have been running nitrous since 2000, and have learned you are in dangerous territory if you are not logging a/f and fuel pressure.

If you are interested I am installing a new twin sensor logging system and will soon be selling my Innovate LM1.

 

[01 RT SNAKE]

Ok I made some progress today and figured out why the car was running so poorly. I took the car to Autozone and they hooked up their OBDII reader and found a low/weak TPS signal code. I unhooked the TPS signal wire (white/red) coming from the FJO, they cleared the code and the car is running like a champ again.

So, what went wrong? Why all of a sudden did the car start having problems with the TPS signal? I have one of those little blue connectors that slices into both wires connecting the two. They're connected right where the TPS orange signal wire goes into the throttle body. I had driven the car for about two weeks prior to arming the system for the first time and it ran great.

Yes, I have new plugs in there that are one step colder.

Yes, I will be getting an air/fuel gauge..probably the Dynotune gauge.

I'm only going to be running a 100 shot until I get used to the new power. I will have it put on the dyno and have the air/fuel checked at that time.

How and where are you activitating (arming your system) the FJO?

I'm using a toggle switch mounted in the ashtray. The power wire was hooked directly to the battery jump start post, the negative was grounded to the frame and the accessory post on the toggle switch is hooked to the white wire of the FJO box. This white is also connected to the #86 red wire on the relay.

The power source (what you will be arming it from inside your car) should go only to the input wire ((Slot A) or the white wire on the FJO I'm also tied into the (86) side of the relay as shown in the instructions) and the (87) side of the relay that is the power source to your NX solenoids. Looking at your relay (power source for the NX solenoids) the (30) should be the direct wire to your battery. 87 should be the side that goes to the solenoids. 85 goes to your FPSS(fuel pressure safety switch) and if you are not running one it needs to be grounded. If you are running a FPSS make sure it's not close to any of your NX solenoids as the interference from the coils will mess with it.

I have my wires exactly as you state.

How are you signaling the FJO? I'm using the TPS wide open throttle option

The white/red (slot B) wire should be your TPS signal. I'm spliced into the TPS but read above, I'm now getting a weak TPS signal for some reason
The red wire (slot C) is not used I'm not using this wire
The green (slot D) wire should go to your tach signal. *This one is important I'm spliced into this wire right as it enters into it's wiring harness

Please use the tach signal and not a coil driver. Unlike the Raptor shift light the FJO can pick up the Vipers Tach signal just make sure your RPM multiplier is set at (divide by 2.5)
I'll get to programing later after you verify your wiring

The FJO Controller gound (slot K-black) and Driver ground (12 AWG black) both should go obviously to a good ground I'm grounded to the frame and verified it's a good ground with a test light.

Then Finally the Blue (stage 1) from the FJO should go to the other side of your NX solenoids. Red (stage 2) not used. I have my gas/nitrous solenoids hooked to this wire.

So your NX solenoid wires (2 each) should only go to the power side of your relay (87) and the blue (12 AWG) stage 1 wire from the FJO. I have the other two wires going to this side of the relay

And you can test your FJO without the car running. I would depressurize your fuel line. NOS empty. Key on engine off. Arming on and flip your TPS and you will hear the solenoids click. I'm assuming that when I program the FJO I don't use the enable first gear lockout option?

Where should my fuses be? NX recommends a 40 amp fuse between the relay and the battery post. I have done this.

FJO recommends a 5 amp fuse on the power side of the arming switch. This is what I keep blowing. I have no clue why. This is the switch mentioned up above that has the white wire coming from the FJO box and is tied into the 86 side of the relay.

Should there be an inline fuse on the power side of the nitrous/gas solenoids that goes into the 87 side of the relay?

For all of those who lent some advice...thanks. I love this board.

Mike

 

[viperrt96]

Mike

Are you sure you tapped into the right wire coming off of your TPS.

It has three.

One is a ground
One is 5v power supply
One is for signal.

Not knowing what color your wires are for your year of car I'm guessing you could have tapped into the 5v power supply and not the signal side. This might have screwed with the signal thus making it weak and the computer not reading it right?.

What is your tach multiplier set at ?
It should be (divide by 2.5)

I forgot to ask what Gen FJO do you have? It should say on the instruction sheet. Make sure you don't have a gen1 (no relation to the viper). All else fails call FJO and ask for Jerry in service. One heck of a guy and he'll help you out.

 

[01 RT SNAKE]

I'm spliced into the orange/blue striped wire. It's the 2nd one down from the top. The top one is black/blue striped and the bottom one is solid orange.

My car is a 2001 and I read on here that 2nd generations are supposed to be tapped into the orange/bue striped wire. Am I wrong? Anyone??

I running the 2nd gen box.

My divider is set at divide by 2.5.

I was reading about low TPS signals last night and found this on a Grand National website.

CODE 22
Trouble Code 22 indicates that the Throttle Position Sensor (TPS) is reading abnormally low. TPS volts should be close to 0.42 V at closed throttle and rise smoothly in about 0.02 volt increments to a maximum reading of about 4.85 volts at WOT.
The conditions for setting this code are:

• the engine is running, and
• TPS reading is < 0.20 volts

Note: During a Code 22 condition, the ECM uses a default TPS value of 2.6 volts. This will cause the engine to idle very high.

Typical causes for this code include:
1) Maladjusted TPS
2) Defective TPS
3) No +5 volt reference to TPS
4) TPS-return to ECM is shorted to ground or to sensor ground
5) Defective ECM
NOTE: The TPS must be adjusted to about 0.42 volts at closed throttle for the ECM to auto-zero properly. If necessary, adjust the TPS to bring the voltage up or down to this value at closed throttle.

Is it possible that when i blew the fuse from the FJO arming switch to the 12v source that the current went somewhere and shorted the sensor momentarily? I also read that once the trouble code is set, the ECM will set a default value to the TP sensor and some vehicle performance will return. My car ran, but not very good. Once the code was cleared, it ran good again.

I've decided to take it slow and start the wiring connection process over. I can't afford to make a costly mistake.

Also, anyone with a gen 2, where are you tapping into a switched 12v power supply? I have 4 open slots on my driver's side fuse panel and none of them are switched power sources.

Mike

 

[viperrt96]

Also, anyone with a gen 2, where are you tapping into a switched 12v power supply? I have 4 open slots on my driver's side fuse panel and none of them are switched power sources.

Mike

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These work nice and you don't have to tap into anything. You should be able to find it at your local auto parts store. They also should have then for both fuse types.

 

[01 RT SNAKE]

I've seen those. Basically, I'd still have a 12v supply constantly going to the switch correct? I was looking for something that was only "hot" when the key was engaged.

Why two "5 amp" fuses? Why not one 10 amp fuse?

Mike

 

[viperrt96]

It's basically a piggyback. The front fuse will continue to fuse your existing accessory (whatever that is) and the back fuse will give power to the wire lead.

As far as being "Hot" when the key is on just take a test light and pick a fuse in the panel (I would pick a 10amp up to a 20amp) randomly that is "Hot" when the key is on. It doesn't take a big draw to arm the FJO. I run a 10 amp fuse and have never blown a fuse.

I run three of them in my fuse box and all of them are 10 amp fused

Two are key "ON or HOT" and one is "HOT" all the time.

Why three?

One is for the arming of the NOS(FJO) - I use my mystery switch (or rear defroster button I think it is?)
One is for the Dual Heaters (power the relays) that I can control individually- I run 2 10lb bottles
One is for the Dual Openers( Control individually) but is hot at all times. Just in case I forget to close one or ?

 

[viperrt96]

Once you get the FJO problem ironed out you'll love what the unit can do for you.

And if you want to see my resume on NOS wiring you should see my Dual Heater/Dual openers and purge pendant. The folowing pic has over 200 feet of wiring in it just for the bottles.

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Here's a the finish product installed

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I didn't want to cut up my dash and this pendant sits nicely next to my leg ready for use. I can open/close or heat any of my bottles individualy while I'm driving. I never have to access my trunk unless to fill the bottles.

 

[viperrt96]

Here's another view of it

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[v10kingsnake]

that fuse is called an add a fuse. fyi.

 

[viperrt96]

I forgot to mention the best accessory you can have when running NOS is a gauge. You've got to know what you have at all times (pressure).

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[Jack B]

I forgot to mention the best accessory you can have when running NOS is a gauge. You've got to know what you have at all times (pressure).

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Just an opinion, an a/f gauge is not bad for low speed tuning, but, is worthless for wot tuning. A logging scheme is a must.