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Spark Blow Out????

  • Thread starter Thread starter MY 85 GT
  • Start date Start date Aug 22, 2013
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MY 85 GT

10 Year Member
Mar 7, 2008
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Aug 22, 2013
#1
  • Aug 22, 2013
  • #1
How long do spark plugs last on a turbo set-up mine are around a little over a yr...I had a water pump failure so I replaced that I installed a flex-a-lite fan..then I was having very low battery voltage so I bought a PA performance 3g alt upgrade ok did that today..took the car for a ride seems nice charges awesome...But now when I get on it start building boost 5 psi and the meth injection activates I get a bog like it cant take the fuel...im thinking spark blow out...plug went bad..got wet from weak spark from low amps before I replaced the Alt?...Any ideas air fuel gauge is reading fine not going lean at all..if I drive the car normal its fine only does it once I go into boost...Oh also car is running anywhere from 180-195 temps im guessing that ok...any help would be great thanks...
 

madspeed

Colonel Mustard
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#2
  • Aug 22, 2013
  • #2
pull codes yet? Is there a custom tune?
 

MY 85 GT

10 Year Member
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Aug 22, 2013
#3
  • Aug 22, 2013
  • #3
no I didn't pull codes..it has a moates chip.Like I said this didn't do this a week ago with the clutch fan..it seem to start after I installed the electric fan and I had the stock Alt...weak spark...now today I installed the 3G alt volts are good now..but im thinking could I have foulded out the plugs..Also they have been in the car for over a yr with 14 psi and meth injection could it just be its time to change them???? they went bad
 

madspeed

Colonel Mustard
Founding Member
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#4
  • Aug 22, 2013
  • #4
i'd start with the codes. Is it a Moates Quarterhorse or just the f3 chip?
 

revhead347

Apparently my ex-husband made that mistake.
20+ Year Stangneter
Jun 14, 2004
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Aug 22, 2013
#5
  • Aug 22, 2013
  • #5
Gap the plugs way down and see if it fixes the problem. If not, then it's not blowing out the spark.

Kurt
 

MY 85 GT

10 Year Member
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Aug 23, 2013
#6
  • Aug 23, 2013
  • #6
Ok whats bothering me here is it never DID this I have had the car done over a yr ago ..the plugs are gapped at .030 and I run a crane HI-6s also this has never done this the whole time the turbo has been on the car for over a yr now just started after the water pump let go and I installed an electric fan...was running a stock Alternator...I then installed a PA performance 3g Alt and it didn't help..i thought it was weak spark due to a Alt that couldn't keep up with the electric fan and all the other draw it had on the old Alt...Just saying this never did it until the water pump let go..now antifreeze did spill all over the place I did clean it all up by washing the motor down....
 

MY 85 GT

10 Year Member
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Aug 23, 2013
#7
  • Aug 23, 2013
  • #7
I pulled one plug this is what it looked like...also there champions RC9YC im not a fan of them the shop installed them..what is a good plug to use with Trickflow 170 cc heads.I also run a snow performance meth kit too....
 

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madspeed

Colonel Mustard
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#8
  • Aug 23, 2013
  • #8
they look fine, but no harm in relacing them with some ngk v powers. I'm running R5671-a9 at the recomendations of many respected engine builders
 

madspeed

Colonel Mustard
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#9
  • Aug 23, 2013
  • #9
....and, you say it never did this ntil you washed the engine, which tells me you got water somewhere it wasnt meant to be. I can almost guarantee that anytime i do this, i have problems afterwards. Which is why I nolonger let my bay get dirty!
 

MY 85 GT

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Aug 23, 2013
#10
  • Aug 23, 2013
  • #10
Yeah the water pump let go out of the weap hole but i didnt get any electrical stuff wet i was careful...Believe me...yeah its so weird unless i just have one bad plug??? that was only 2 i pulled on the drivers side the easy ones to get to...Im also wondering if a wire is bad...normal driving its fine but under a load it cant keep up??? Oh would any one know what NGK plug i can use for a Trickflow 1700cc head????

You said they look fine not lean? i know there clean from the meth injection..wonder if the meth is doing something to them???
 

madspeed

Colonel Mustard
Founding Member
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#11
  • Aug 23, 2013
  • #11
same plug i listed will work in your heads. Here,s a nice listing for ou to bookmark

http://www.theturboforums.com/threads/281795-Spark-Plug-FAQ?highlight=ngk+5671-8
 

GroverDill

GoldMember
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Aug 23, 2013
#12
  • Aug 23, 2013
  • #12
that gap looks pretty big i run .023 on mine per kurgans recommendation
 

revhead347

Apparently my ex-husband made that mistake.
20+ Year Stangneter
Jun 14, 2004
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Acworth, GA
Aug 23, 2013
#13
  • Aug 23, 2013
  • #13
That gap does look big. It's not uncommon to have to gap down to .025 on a turbo car.

Kurt
 

MY 85 GT

10 Year Member
Mar 7, 2008
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Aug 23, 2013
#14
  • Aug 23, 2013
  • #14
I agree...Now like i said i have had the car together for over a yr Never had this issue...Only started after the water pump and electric fan install...Question does the gap open up after time..Meaning is it possible they were gapped smaller and with heat etc...the gap open up some????
 

madspeed

Colonel Mustard
Founding Member
Nov 29, 1999
8,914
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a van down by the river
Aug 23, 2013
#15
  • Aug 23, 2013
  • #15
yes, the gap opens as the plug wears. Throw a gap gauge on em, what are they reading?
 

MY 85 GT

10 Year Member
Mar 7, 2008
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Aug 23, 2013
#16
  • Aug 23, 2013
  • #16
madspeed said:
yes, the gap opens as the plug wears. Throw a gap gauge on em, what are they reading?
Click to expand...

.o30 on the 2 i pulled out, so now im thinking is it possible they had them closed up more and there just wearing and i could have fouled one with the weak spark and im noticing it now more so??? there a yr and half old and i run 14 psi...and i drove the car alot...didnt beat on it so much but drove it daily...
 

madspeed

Colonel Mustard
Founding Member
Nov 29, 1999
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Aug 23, 2013
#17
  • Aug 23, 2013
  • #17
mine are at .030 runing 10# boost
 

MY 85 GT

10 Year Member
Mar 7, 2008
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Aug 23, 2013
#18
  • Aug 23, 2013
  • #18
Ok so im guessing thats not the problem...lol...
 

GroverDill

GoldMember
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Aug 23, 2013
#19
  • Aug 23, 2013
  • #19
nice nails.
 

MY 85 GT

10 Year Member
Mar 7, 2008
1,852
208
104
New Jersey
Aug 23, 2013
#20
  • Aug 23, 2013
  • #20
GroverDill said:
nice nails.
Click to expand...
..

LOL thats my wife i had her hold the plug...
 
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