Spark Plug Question

[BruceH]

Hey guys, so I installed a Procharger system on my 2006 Mustang GT and im running Autolite HT0s in the car. So my problem is that when i first start the car it comes on with no issues , starts right up. The idle seems pretty normal except for a slight bounce from the normal 750ish to about 500ish every so often. I do not know if the slight bounce in the idle is normal with the extra load from the procharger belt, or if it is being caused by something else. Now when i drive the car for a little while and the engine gets warmed up, when i go into neutral the engine rpm will drop to 500 and then the engine will die out. From this point when i start the car back up it will come on and then almost die again immediately. My first instinct is that maybe the spark plug gap is wrong leading to fouled plugs and engine stalling at idle. What do you guys think? Any help is appreciated thank you

There are several tables and parameters that affect idle. A good tuner will be able to stabilize most of what's going on provided that you don't have any unmetered air coming in or other mechanical issues. .032 gap works just fine as do ht0 plugs. The ecu will self adjust the idle to an extent so it might get better as time goes on. It's still preferable to have the tune as close as possible.

Are you running stock cams? How did you set up the pcv? Was it like procharger instructs or did you do something different? Procharger has has different directions for the pcv over the years but at one time they had the hybrid setup in the installation directions. Pcv setup made a big difference with my procharger. The 3v pcv is designed to draw air from the passenger side and vent it through the driver side valve cover into the intake.

I ended up running a hybrid setup. Remote breather on the passenger side and driver side was connected to the intake with the extra pcv that procharger supplied. This goes against what many smart people say will work. My guess is that the small amount of unmetered air coming from the crankcase is a very small portion of what's coming through the tb and is inconsequential. I'm also of the opinion that the motor works better with the vacuum that's provided by a pcv system.

Edit: The reason I described the hybrid setup for pcv is because that's the one that gave me the best idle. Running breathers didn't work well at all for the motor I had at the time.

 

[nicks1031]

There are several tables and parameters that affect idle. A good tuner will be able to stabilize most of what's going on provided that you don't have any unmetered air coming in or other mechanical issues. .032 gap works just fine as do ht0 plugs. The ecu will self adjust the idle to an extent so it might get better as time goes on. It's still preferable to have the tune as close as possible.

Are you running stock cams? How did you set up the pcv? Was it like procharger instructs or did you do something different? Procharger has has different directions for the pcv over the years but at one time they had the hybrid setup in the installation directions. Pcv setup made a big difference with my procharger. The 3v pcv is designed to draw air from the passenger side and vent it through the driver side valve cover into the intake.

I ended up running a hybrid setup. Remote breather on the passenger side and driver side was connected to the intake with the extra pcv that procharger supplied. This goes against what many smart people say will work. My guess is that the small amount of unmetered air coming from the crankcase is a very small portion of what's coming through the tb and is inconsequential. I'm also of the opinion that the motor works better with the vacuum that's provided by a pcv system.

Edit: The reason I described the hybrid setup for pcv is because that's the one that gave me the best idle. Running breathers didn't work well at all for the motor I had at the time.

I have a breather set up on the passenger side, and the driver side is capped off as said in the Procharger book. Im running a smaller filter directly on the head unit instead of the intake tube over the headers. Can provide pics if you want

 

[retfr8flyr]

Okay so I have an update on my situation, I switched plugs, I went with Brisk 3VR14S plugs gapped at .032 (Confirmed that plugs before were not gapped properly, they were bigger than .04) and I cleaned my MAF sensor. Car is no longer stalling at idle when warm which is nice, idle still slightly bouncing but not as much as before. Do you guys think the car is at least safe to slow poke around for now until I get on the dyno to dial it all in at the end of the month?

I think it would be safe, as long as you don't get into boost, until you get your dyno tune.

 

[gtman]

I think it would be safe, as long as you don't get into boost, until you get your dyno tune.

Id bet pbh happily supplies a start up tune to get there if he can get his handheld tuner there with any other car/mail,etc.

 

[BruceH]

I have a breather set up on the passenger side, and the driver side is capped off as said in the Procharger book. Im running a smaller filter directly on the head unit instead of the intake tube over the headers. Can provide pics if you want

FWIW I could never get that setup to idle very well at all. I am of the opinion that the motor is fighting itself at lower rpm due to the absence of a good vacuum to vacate the crankcase pressure. When I tried mine with the capped and one breather setup it resulted in a lot of oil being pushed through the only breather.

Your 3v will adjust a/f on the fly in closed loop. This means that like the others have said as long as you keep it out of open loop (wot) your motor should be fine until you get a custom tune.

 

[nicks1031]

Yeah car seems too run completely fine other than the slightly bouncy idle now, thanks for all the input everyone

 

[Stephen31201]

Spark plug gap is a game changer on blown cars! HT0s are .045 out of the box. Took them back out, gapped them correctly and it was like adding Nitrous. Also, for what its worth, buy a Bluetooth OBD2 adapter and download the app on your smartphone. I keep my iPhone mounted on the dash while driving and it allows you to monitor almost everything you want, including STFTs and LTFTs, IATs, Detonation Knock, and accurate ECT (cause the stock one is a joke). Unfortunately not AF ratio, but that's another purchase. I paid $20 for mine and it works like a champ. Just a little way to datalog visually all the time.

PS keep your appointment. Every car is different and a custom tune for your car is worth the $.