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Msd system now MAJOR blow by?

  • Thread starter Thread starter J90GT
  • Start date Start date Oct 21, 2005
J

J90GT

New Member
Sep 15, 2005
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0
Oct 21, 2005
#1
  • Oct 21, 2005
  • #1
Alrighty, i just installed the whole msd deal (box,coil,wires,rotor,cap, plugs). So i take it out for a spin seems fine get on it a bit, still seems good. Then i notice my idle goes way down to around 400 which turns into backfiring and pretty ,much not being able to idle without holding down the gas.


Im like WTF, pull over and my oil breather(yes the filter) is totally blown off, I put it back on, she runs good again. Now i get back on my street and let her rip again, except at the top of second ended in a big backfire and more crap idle i pull in my drive way and sure enough the breather blow off again.



Now, the breather cap on my car is rather cheap and just has a rubber grommet at the bottm and kinda pops in but why after i install the msd i cant even give my car some decent gas without blowing the breather completey off which inturn makes my car run like **** due to the huge vac leak it creates?
 

nosmatt

Founding Member
Oct 13, 2000
1,356
0
37
Bass Lake, Ca
Oct 21, 2005
#2
  • Oct 21, 2005
  • #2
totally unrelated. looks elsewhere for your problem.


i would advise a leakdown test personally.......at the VERY LEAST, a compression test.
 
J

J90GT

New Member
Sep 15, 2005
73
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0
Oct 21, 2005
#3
  • Oct 21, 2005
  • #3
Hmmmmmm strange coincidence i guess
 

Black1987Stang

Active Member
Aug 22, 2004
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37
Jersey Shore
Oct 22, 2005
#4
  • Oct 22, 2005
  • #4
u could always disconnect the stuff u just hooked to see if it could be somehow the problem, for the msd box just unplug the ground for the box and reconnect the car harness back into the stock/msd coil. Elimnate one by one and if its fixed youll know whats causing it. Always check the simple stuff first, well thats me and also the stuff that doesnt cost money to do haha Good Luck
 

18mustangs

New Member
Jun 8, 2005
533
1
0
Virginia Beach, VA
Oct 22, 2005
#5
  • Oct 22, 2005
  • #5
J90GT said:
Alrighty, i just installed the whole msd deal (box,coil,wires,rotor,cap, plugs). So i take it out for a spin seems fine get on it a bit, still seems good. Then i notice my idle goes way down to around 400 which turns into backfiring and pretty ,much not being able to idle without holding down the gas.


Im like WTF, pull over and my oil breather(yes the filter) is totally blown off, I put it back on, she runs good again. Now i get back on my street and let her rip again, except at the top of second ended in a big backfire and more crap idle i pull in my drive way and sure enough the breather blow off again.



Now, the breather cap on my car is rather cheap and just has a rubber grommet at the bottm and kinda pops in but why after i install the msd i cant even give my car some decent gas without blowing the breather completey off which inturn makes my car run like **** due to the huge vac leak it creates?
Click to expand...

This problem is totally unrelated to the MSD. You've got excess crankcase pressure. Ditch the breather cap and run this cap View attachment 499842 part # M-6766-D302** from fordracingparts.com. It allows your PCV system (which ventilates your crankcase and also prevent excess crankcase pressure which can blow out your oil filler cap or have oil leak from seals) to work properly. When you run this cap (it plugs into the VC just like your current push in cap) hook the throttle body tube to the port on the cap, and then make sure you replace your PCV filter, PCV grommet, and PCV valve and make sure your PCV hoses have no kinks behind your upper intake. Your car will run much better afterwards.
Tim
 
J

J90GT

New Member
Sep 15, 2005
73
0
0
Oct 22, 2005
#6
  • Oct 22, 2005
  • #6
Yes, like i said maybe just coincidence cause i never had the problem before i installed it. Really hard to say a hotter ignition causes blow by unless my old ignition was just totally in the ****ty but even than thats a real stretch.


I'll try that cap 18mustangs thanks
 

RsStanG1987

I shaved all my pubes playing this game.
10 Year Member
Mar 13, 2004
569
9
79
Dupont PA
Oct 22, 2005
#7
  • Oct 22, 2005
  • #7
Yeah your ignition DOES NOT have a thing to do with your blow by at all. You probabbly all ready had pretty bad blow by and never noticed it till now. Do a compression test asap.
 

18mustangs

New Member
Jun 8, 2005
533
1
0
Virginia Beach, VA
Oct 22, 2005
#8
  • Oct 22, 2005
  • #8
J90GT said:
Yes, like i said maybe just coincidence cause i never had the problem before i installed it. Really hard to say a hotter ignition causes blow by unless my old ignition was just totally in the ****ty but even than thats a real stretch.
I'll try that cap 18mustangs thanks
Click to expand...

No problem, I used to be a breather cap man until I read how the PCV system works and how efficient it is (amazingly enough, the Ford engineers really do know what they're doing!). If you spend the approximately $30 for the oil cap, PCV filter, grommet, and valve you'll notice a difference. BTW, the oil cap is only $7.50 and has a built in oil baffle.
Tim
 
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