BLACK Sparkplugs... fouling... Supercharger build startup help. 50psi fuel at idle.

[-FROG-]

Posting this on both boards for a quicker response. I started my car yesterday for the first time since my Paxton build. It starts up fine but I have been trying to find out how to route the vaccum lines so it idles properly. The vaccum lines I am talking about are the ones up in the front of the intake in between the throttle bodies, that went to the charcoal canister (I yanked out the canister and all that emissions junk). Sometimes it idles bad ass, like it has a really lumpy cam, but most of the time, it idles really out of sync and has a really strong exhaust smell. A few times it got to where it wouldn't even start at all, I guess due to the fouling plugs... last night it wouldn't start, so I let it sit over night and this morning before work I started it and it started up STRONG and sounded insane! After work, I installed the new plugs and then started it up and it seemed pretty strong again, so I was happy, but then, it sounded like it got "out of sync" again and wasn't running right. I messed with it about an hour or so , tinkering with the IAC hose and experimenting with a little filter on the IAC and what not... Then I decided to pull a plug and it was solid black, like the old ones I pulled out. I say old plugs, but the old ones were only on for a few miles right before I started the Paxton project, so they were pretty much brand new too, just the wrong plugs. So, m I running too much fuel? I thought it was supposed to be at 50psi at idle according to Paxton and what I have seen on my research on the boards.

I know I had the wrong plugs in the car but for a few quick starts yesterday, I figured they would be fine. Today, I bought some NGK's. From all of my research, I bought the ones that most are using the 4644 (BKR7E) gapped at 30.

So when I took the old plugs out to install the NGK's I noticed they were all solid black.

Old plugs on left. New NGK on right:

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For the vaccume lines, I ran the small one on the top right, to my Blow Off Valve. The 2 really big vaccum ports on the bottom on each side, I connected together as a crossover to each bank, like it was originally set up. The top left, smaller one, I ran to my Fuel Gauge.

My fuel gauge is at about 50psi unplugged and about 47psi when unplugged. Is this still too much fuel? I have Injector Dynamics ID1000 in there as well. I know my car needs to be tuned properly, but for a startup at idle and staying out of boost, I would think it would be easier to get this thing settled in. Any ideas?

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[Nine Ball]

Re: BLACK Sparkplugs... fouling... Supercharger build startup help. 50psi fuel at idl

You'll continue to foul them out until you get a custom tune done. Fuel pressure is not the proper method for adjusting lean/rich mixture. On the Gen 3, we set it at 58 psi (unplugged, at idle). My Paxton '06 fouled two sets of plugs during the dyno tune session, until it was set up properly.

I'd suggest not driving it until you get a tune.

 

[speedracervr4]

Re: BLACK Sparkplugs... fouling... Supercharger build startup help. 50psi fuel at idl

Do you have a wideband to tell you the a/ f at idle? If there is a large vacuum leak the pcm could be dumping fuel to compensate.

 

[mjorgensen Woodhouse]

Re: BLACK Sparkplugs... fouling... Supercharger build startup help. 50psi fuel at idl

Are you using the Paxton fuel enrichment or something else? What are you tuning with?

 

[-FROG-]

Re: BLACK Sparkplugs... fouling... Supercharger build startup help. 50psi fuel at idl

You'll continue to foul them out until you get a custom tune done. Fuel pressure is not the proper method for adjusting lean/rich mixture. On the Gen 3, we set it at 58 psi (unplugged, at idle). My Paxton '06 fouled two sets of plugs during the dyno tune session, until it was set up properly.

I'd suggest not driving it until you get a tune.

That was my primary thought as well. May be that the spark isn't tuned and that's why fuel is overpowering. Thanks.

Do you have a wideband to tell you the a/ f at idle? If there is a large vacuum leak the pcm could be dumping fuel to compensate.

I do have a wideband, but it's anywhere from 10 to 12 at idle... I always read where Wideband is useless at idle, it's designed more to gage A/F at WOT, so I didn;t pay much attention to it. I will consider checking it and see where it sits when it idles down. I want to say it hoovers more around 12 each time I looked at it when it settles down.

Are you using the Paxton fuel enrichment or something else? What are you tuning with?

I built a full fuel system with (2) 255 in take pumps, Injector Dynamics ID1000 injectors and will be using SCT for tuning. I'm waiting to hear back from the guy that may tune my car, who is just down the street from me, about 8 miles away.

 

[uvbnbit]

Re: BLACK Sparkplugs... fouling... Supercharger build startup help. 50psi fuel at idl

At idle, shouldn't it be 14.7? mine usually bounces around 14-16 at idle.
10-12 is WAY rich. PCM must be adding fuel as mentioned above.

 

[speedracervr4]

Re: BLACK Sparkplugs... fouling... Supercharger build startup help. 50psi fuel at idl

Yea my 99 GTS idles at 14-16 as well and my SRT 10 ram is right at 14.7-14.9. The tuner needs to compensate for the bigger injectors. Has he done this yet? If not I would ask him to build a base map for you before driving it.

 

[-FROG-]

Re: BLACK Sparkplugs... fouling... Supercharger build startup help. 50psi fuel at idl

At idle, shouldn't it be 14.7? mine usually bounces around 14-16 at idle.
10-12 is WAY rich. PCM must be adding fuel as mentioned above.

Yea mine bounces around a bit so I didn't really pay attention to it, but I will say that I don't think it has gone into 14 as of yet. And if the PCM is dumping fuel, then I guess there is nothing I can do till it has a proper tune. I was hoping, adjusting the fuel pressure on the regulator, would give me some influence on the tuning but it may be all from the PCM at this point.

 

[-FROG-]

Re: BLACK Sparkplugs... fouling... Supercharger build startup help. 50psi fuel at idl

Yea my 99 GTS idles at 14-16 as well and my SRT 10 ram is right at 14.7-14.9. The tuner needs to compensate for the bigger injectors. Has he done this yet? If not I would ask him to build a base map for you before driving it.

Ok this is starting to make more sense as you guys are telling my proper numbers for A/F at idle which I am not seeing on my car. No tune has been done to compensate for anything. I'm using an SCT XCal tuner and I only have 2 tunes left so I have to wait and get it on the dyno for any tunes to be made. I guess I'll be looking at towing the car to the tuner at some point if I can get in on their list. I guess driving it the 8 miles would be too risky.

 

[Viper Specialty]

Re: BLACK Sparkplugs... fouling... Supercharger build startup help. 50psi fuel at idl

I built a full fuel system with (2) 255 in take pumps, Injector Dynamics ID1000 injectors and will be using SCT for tuning. I'm waiting to hear back from the guy that may tune my car, who is just down the street from me, about 8 miles away.

Well there is your problem right there, staring you in the face. You have fuel injectors 3x larger than stock installed, and a PCM that is not scaled correctly to control them. Your PCM is not adding fuel, it just cannot remove nearly enough.

Do NOT try to use fuel pressure to influence AFR.

I also see another problem... you have a boost referenced regulator connected directly to your manifold. You cannot do that as it will pull your pressure down on vacuum, and then spike it WAAAAAY higher than expected on boost.

For anyone reading: BOOST REFERENCED REGULATORS ARE NOT SUPPOSED TO SEE VACUUM! CONNECT TO YOUR CHARGE PIPING BEFORE THE THROTTLE BODIES!

Another word of caution, if you are thinking of taking this car to an SCT tuner unfamiliar with Vipers, think again. Scaling injectors is not the easiest thing to do correctly, and it can creep up later if its wrong. Add that to the fact that 99% of outside shops tune the JTEC's completely incorrectly and use the wrong tables to tune- hell, even some Viper shops make this mistake. I see it constantly.

 

[uvbnbit]

Re: BLACK Sparkplugs... fouling... Supercharger build startup help. 50psi fuel at idl

Where are the upstream O2's located?

 

[drlee50]

Re: BLACK Sparkplugs... fouling... Supercharger build startup help. 50psi fuel at idl

I dont agree with the point that boost referenced regulators cant see vac. there are literally 10s of thousands of them doing so in the mustang world alone and they run just fine. I am running mine on my viper that way and there are no spikes at all. if there was a fuel pressure spike, that would mean there was some sort of boost pressure spike-- if thats the case, you need a different boost controller. its perfectly fine to pull the pressure down in vac. the car can be tuned just fine in that condition. its only going to go down a couple pounds or pressure anyway-- certainly not going to hurt your car when you have no load on it-- most peg 20+ afr when you let out of the throttle when you end a wot pull anyway-- this clean the combustion chamber out so you dont foul your plugs. what kind of a spike have you seen?? I would argue any spike you saw was the result of a cheap ass regulator. his aeromotive will not spike at all.

I totally agree with everything else-- you need to scale your injectors dude!! Call you tuner, have him send you at least a base map with the injectors scaled, and you will be able to drive to the dyno just fine. He shouldnt charge you extra for that-- he is going to have to do that anyway. dont drive the car til then-- you are going to wash your cyl walls with fuel and screw up your rings seal.

 

[Viper Specialty]

Re: BLACK Sparkplugs... fouling... Supercharger build startup help. 50psi fuel at idl

I dont agree with the point that boost referenced regulators cant see vac. there are literally 10s of thousands of them doing so in the mustang world alone and they run just fine. I am running mine on my viper that way and there are no spikes at all. if there was a fuel pressure spike, that would mean there was some sort of boost pressure spike-- if thats the case, you need a different boost controller. its perfectly fine to pull the pressure down in vac. the car can be tuned just fine in that condition. its only going to go down a couple pounds or pressure anyway-- certainly not going to hurt your car when you have no load on it-- most peg 20+ afr when you let out of the throttle when you end a wot pull anyway-- this clean the combustion chamber out so you dont foul your plugs. what kind of a spike have you seen?? I would argue any spike you saw was the result of a cheap ass regulator. his aeromotive will not spike at all.

I totally agree with everything else-- you need to scale your injectors dude!! Call you tuner, have him send you at least a base map with the injectors scaled, and you will be able to drive to the dyno just fine. He shouldnt charge you extra for that-- he is going to have to do that anyway. dont drive the car til then-- you are going to wash your cyl walls with fuel and screw up your rings seal.

The whole point of a boost referenced regulator is just that- to reference boost. It causes the pressure differential between one side of the injector to the other to remain constant.

It is fairly common to reference vacuum if you are trying to make injectors too large for an application "behave" better under low loads, and it can of course be done if you tune that way FROM SCRATCH- and there is no way he is going to want to do that pointlessly. The problem is that the Viper's base fuel tables were designed around a steady base fuel pressure, NOT a fuel pressure which becomes lower in deeper vacuum. If you effectively remove 1Bar of fuel pressure in deep vacuum, you just skewed your entire fuel table lean anywhere under 1 ATM, and your adaptives are now going to wander all over the place trying to correct for this constantly.

In a 1:1 boost referenced regulator, you will see a ~12psi fuel pressure drop [as high as ~14 in some cars] in most cases between ATM and deep vacuum. This has nothing to do with regulator quality, the only regulators we use are Weldon.

 

[-FROG-]

Re: BLACK Sparkplugs... fouling... Supercharger build startup help. 50psi fuel at idl

Where or how would you recommend I connect the regulator vaccum line?

 

[-FROG-]

Re: BLACK Sparkplugs... fouling... Supercharger build startup help. 50psi fuel at idl

Where are the upstream O2's located?

All my 02's are in stock locations.

 

[got one]

Re: BLACK Sparkplugs... fouling... Supercharger build startup help. 50psi fuel at idl

Frog...just take it to ART!