NGK Iridium Sparkplugs Problem!

[The '01 Beast]

I installed NGK Iridium Sparkplugs in my semi-modified '01 GT thinking it would be a good addition for my pony. However, my beast has been acting strange ever since putting them in. I have an AODE tranny with a 2400 stall torque converter and when I shift it into reverse the tach drops below 500 RPMs for a few seconds and the car wants to stall. Also, if I step on the gas and come to a quick stop the tach responds the same way dropping below 500. My beast stalled out on me several times when I am making a sharp turn and I step on the gas then quickly brake. These problems are very noticeable when the weather is below 40 degrees. I live in Jersey, so this could be a problem ALL winter long.

Can anyone shed some light on the NGK Iridium plugs? Did I blow about $60 installing garbage in my Stang? Any and all recommendations are appreciated.




Mods:
MAC Cold Air Induction
Accufab 70MM TB
Diablosports Custom Tuned Performance Chip
Level 10 Performance Torque Converter (2400 stall)
Level 10 Performance Shift Kit
3.73 Ford Racing Gears
MAC O/R H-Pipe
3-Chamber Flowmaster Cat-Back (not my choice, but the car used and the previous owner dropped it in)
4" Dynomax Chrome Exhaust Tips (20" length)
Cobra R 2.5" Cowl w/ '96 Cobra Scoops
Mach 1 Grill Delete Kit
Mach 1 Chin Spoiler
17" Cobra R Chrome Rims

 

[rx7speed]

I would almost think something else is wrong there

sharp turns and hitting the brake should not have an effect on the ignition


not too sure of how the motor bay is but you might want to check to make sure didn't knock a vac line loose

and also I would say check your IAC


other then that I have no idea nor do I even know why the IAC would go out but I am just saying it is worth a shot

 

[The '01 Beast]

I would almost think something else is wrong there

sharp turns and hitting the brake should not have an effect on the ignition


not too sure of how the motor bay is but you might want to check to make sure didn't knock a vac line loose

and also I would say check your IAC


other then that I have no idea nor do I even know why the IAC would go out but I am just saying it is worth a shot

Thanks Stanger! I appreciate your feedback. I just set up an appointment to have my car dynoed at Crazy Horse Industries tomorrow, so I will have someone take a look at it.

 

[99SilverGT]

I'll almost guarantee you that its merely coincidence. The problem you describe fits what rx7speed already said. I'll bet you its your IAC. It causes the engine to idle very low when your foot is off the gas.

When mine went bad it would barely idle in neutral. When I put the clutch in and shifted gears the RPMs would drop like a rock all the way down to 500 or less instead of hovering like they should so you can shift smoothly.

IAC is located on the front of the throttle body and attaches with two bolts, one on top and one on the bottom. Its "L" shaped and comes off and goes towards the passenger side of the car. There is a plug on that end of it.

Good luck on the dyno!

 

[The '01 Beast]

I'll almost guarantee you that its merely coincidence. The problem you describe fits what rx7speed already said. I'll bet you its your IAC. It causes the engine to idle very low when your foot is off the gas.

When mine went bad it would barely idle in neutral. When I put the clutch in and shifted gears the RPMs would drop like a rock all the way down to 500 or less instead of hovering like they should so you can shift smoothly.

IAC is located on the front of the throttle body and attaches with two bolts, one on top and one on the bottom. Its "L" shaped and comes off and goes towards the passenger side of the car. There is a plug on that end of it.

Good luck on the dyno!

Hey thanks for the info 99! As soon as I get home from work I will check out the IAC to see if possibly there is debris on or near it. The passenger side functional scoop on my Cobra R hood is right above the TB, so possibly the IAC got wet during this past weekend's snow storm and heavy rain downpour yesterday. I rigged some sort of funnel underneath the hood so that my engine does not get wet, but it's not a 100% guarantee.

With my mods I am hoping to get 260 to the wheels (305 flywheel). I will post my results hopefully sometime this weekend.

 

[el_kid_1]

It could also be a sign that the TPS is about to go bad. It happened to me.

 

[99SilverGT]

Hey thanks for the info 99! As soon as I get home from work I will check out the IAC to see if possibly there is debris on or near it. The passenger side functional scoop on my Cobra R hood is right above the TB, so possibly the IAC got wet during this past weekend's snow storm and heavy rain downpour yesterday. I rigged some sort of funnel underneath the hood so that my engine does not get wet, but it's not a 100% guarantee.

With my mods I am hoping to get 260 to the wheels (305 flywheel). I will post my results hopefully sometime this weekend.

Sorry, should have elaborated a little more. The IAC actually goes bad from carbon buildup on its internal parts. Once it goes, its gone, some people try to clean them, but it pretty much doesnt work and if it does, you'll have problems again soon. Water also won't affect it because its pretty much completely sealed, I think the only thing where water could get in would be on the motor and if it did that you'd probably have total failure.

You can pick up a new one at most part stores for around $50-60. They might have to order it for you.

 

[rx7speed]

lucky guys

my BAC (bypass air control, same thing as an IAC) is about 199


but also to give a little better idea on what it does just incase your not sure is controll the idle speed when you apply load to the motor at idle
you know hitting the brakes, A/C lights, something like that which can put enough load to stall the car out

the way they work (least taking my BAC as an example) is letting air bypass the Throttle body to go into the motor letting it maintain a steady idle

now there are a few different designs some are stepper motors where they only open so much depending on how much extra air you need to keep the idle at 750 with the added load

others are the type that open and close
and the faster they open and close the more air it allows in the motor again to maintain that idle


carbon buildup can kill them
but also you might want to check the connections just to make sure you didn't bump something loose

as far as testing them I don't know
know on the rx7 you can put a 12v power supply and listen to it so see if it opens.. with the stang I'm not sure though if that would wok you might wish to ask around a little further

also put a vac tester on your car just to make sure your not running low vac from a leak somewhere


if you already know this info I'm sorry just trying to give a little help