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Big Problems - help please - can't get it running right

  • Thread starter Thread starter Paul Perreca
  • Start date Start date Nov 12, 2005
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Paul Perreca

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Mar 30, 2005
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Nov 12, 2005
#1
  • Nov 12, 2005
  • #1
it runs, it does not idle AT ALL - when you let the R's go down and than you get them back up it backfires n puts and backfires - the spark plugs are black and they are bran new, the thing is running rich as all hell - what in the HELLLLLLLLLLLLLLLLLLL am i supposed to adjust?? i figured i'd look at the surging idle checklist, but honestly, i have no idea what the **** any of that **** is and i don't know how to adjust it- i am at a complete, full days wasted loss
 

Michael Yount

Mustang Master
Apr 10, 2002
9,039
6
79
Charlotte, NC
Nov 12, 2005
#2
  • Nov 12, 2005
  • #2
Back up there orange-peel-man. What did you do/change/install? Was it EVER running right before you changed something? If so, what did you change -- give us lots of detail.
 

Nutzy19

Member
Mar 30, 2005
120
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16
Flemington NJ
Nov 12, 2005
#3
  • Nov 12, 2005
  • #3
check that firing order dude...
 

Paul Perreca

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Mar 30, 2005
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#4
  • Nov 12, 2005
  • #4
the firing orders has been double n triple checked lol - Mr. Yount... Shortblock - E-303 camshaft, Edelbrock RPM heads - cobra intake, 70 mm throttle -

MASS AIR CONVERSION - 76mm C&L MAF -

we just put the engine in, and have been hooking things up for about 3 weeks - finally started it today, and it started, runs good when you keep the throttle into 2000 RPMS - when u let off - it dies - when you move the R's around, the exhaust AND intake (right by the massair meter) pop and backfire n do goofy **** - Must have some answers, will not sleep until it runs good lol help guys, appreciate everything !!!

and NO it was never running right, this is a bran new 302 shortblock that we built, and this is it's first firing up - and the spintechs sound goddamn mean by the way, at 2000 R's, the spintechs humm "beeeeeeeaaaaaasssssttttt" lol

But anyway - aside from the gay mufflers, i gotta get this thing in check, before i have to have a professional look at it - thanks again guys!!
 

Grn92LX

Fidanza Man!
Founding Member
Jan 14, 2001
6,819
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129
New York
Nov 12, 2005
#5
  • Nov 12, 2005
  • #5
Paul, sounds like you have a vacuum leak. What gave it away was the lean pops you hear through the MAF. Vacuum leaks in an EFI car = a lean condition since you are letting in unmetered air.

When I first got my 347 running I had the exact same issue. Lean pops and it wouldn't idle. I ended up not capping off one of the many vaccum ports on the upper manifold and i had a leak at the lower manifold too.
 
S

spittinstang

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Nov 12, 2005
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Nov 12, 2005
#6
  • Nov 12, 2005
  • #6
sounds like you got a lower intake leak. plugs are pry black from oil lrrking into intake ports on head. pull your dipstick and see if your oil smells like gas. if it does you know thats the problem.
 
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spittinstang

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Nov 12, 2005
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#7
  • Nov 12, 2005
  • #7
also what intake gaskets did you use? dont use the perma tourques on the alluminum heads. make sure to use printo seals.
 

sweet88gt

Member
Jun 25, 2005
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16
Venice FL
Nov 12, 2005
#8
  • Nov 12, 2005
  • #8
Check the timing or at least mess with the timing so you can get it run. After that check hard and close for vac leaks. Popping thru the intake sounds like it is a timing issue. Start there and see what happens.
 

Paul Perreca

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Mar 30, 2005
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Nov 12, 2005
#9
  • Nov 12, 2005
  • #9
spittinstang said:
sounds like you got a lower intake leak. plugs are pry black from oil lrrking into intake ports on head. pull your dipstick and see if your oil smells like gas. if it does you know thats the problem.
Click to expand...

does this mean i am totally screwed and have aloootttt more work to do? damnit dude - if my oil smells like gas i'm comin after you, and thankin u lol i will check asap -

and Grn92LX - when u say lean, what do u mean by that, because thought i was getting TOO much gas - where the hell do i look for a vac leak? i have all my smog stuff plugged off, and the heads don't have any smog stuff, and the intake is all hooked up - could i have vaccuum lines mixed up? in wrong spots? help - lol
 

Modular2v

Founding Member
Jun 30, 2002
3,222
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oklahoma
Nov 12, 2005
#10
  • Nov 12, 2005
  • #10
is the map sensor pulgged in?
 

88GTtom

Member
Oct 22, 2003
198
0
17
Woodbridge NJ
Nov 12, 2005
#11
  • Nov 12, 2005
  • #11
is your maf calibrated for those injectors?
 

Grn92LX

Fidanza Man!
Founding Member
Jan 14, 2001
6,819
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129
New York
Nov 12, 2005
#12
  • Nov 12, 2005
  • #12
Paul Perreca said:
and Grn92LX - when u say lean, what do u mean by that, because thought i was getting TOO much gas - where the hell do i look for a vac leak? i have all my smog stuff plugged off, and the heads don't have any smog stuff, and the intake is all hooked up - could i have vaccuum lines mixed up? in wrong spots? help - lol
Click to expand...

Start spraying carb cleaner around where the lower intake meets the head or any other suspected area. When I say lean, meaning not enough fuel.

Are you sure you followed the cobra intake vacuum line routing properly? There is a nice helpful pic floating around the net.

You could also have the rockers adjusted wrong.
 

Michael Yount

Mustang Master
Apr 10, 2002
9,039
6
79
Charlotte, NC
Nov 12, 2005
#13
  • Nov 12, 2005
  • #13
Did you degree the camshaft upon install? Did you do the maf conversion as a part of the changes? As mentioned above, when you do that the MAP (manifold absolute pressure) sensor becomes a BAP (barometric absolute pressure) sensor and the vacuum port should be left open to the atmosphere, not plugged into the manifold like it is with the speed density system.
 

Paul Perreca

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Mar 30, 2005
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Nov 12, 2005
#14
  • Nov 12, 2005
  • #14
good tips - will definately be checking up on this stuff - i hope the rockers are correct, and we did not degree the cam, it just went right in lol - neway - seriously appreciated - i'll get back to you on progress on wednsday, because we are too busy to worko n it again till then lol
THANKS!
 

Paul Perreca

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Mar 30, 2005
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Nov 13, 2005
#15
  • Nov 13, 2005
  • #15
where is the map sensor? i may get it running tonight if u tell me
 

DMAN302

My mom says thanks for the pearl necklace.
Nov 8, 2003
2,120
2
59
windsor, Canada
Nov 13, 2005
#16
  • Nov 13, 2005
  • #16
Paul..first check your TPS setting. Next pull the codes with the engine off. Next check all your vac lines to ensure they are connected..all of them including canister and PCV. If you didn't degree the cam did you install it dot to dot? Are you sure you did all the required wire swaps for the Mass air conversion..double triple check your wires. Did you get the grounds in place and secure on steel surface, not painted?Is the orange ground wire by the passenger firewall connected? All I can think of for you to check..but keep at it.
 

DMAN302

My mom says thanks for the pearl necklace.
Nov 8, 2003
2,120
2
59
windsor, Canada
Nov 13, 2005
#17
  • Nov 13, 2005
  • #17
Map sensor is the little box item attached by bracket to the firewall to the left of the vacuume tree.
 

Michael Yount

Mustang Master
Apr 10, 2002
9,039
6
79
Charlotte, NC
Nov 13, 2005
#18
  • Nov 13, 2005
  • #18
That sensor with the maf conversion is now your BAP sensor -- it should be plugged into the computer (wiring harness) but should NOT be connected to the intake -- the port on the sensor should be left open to the atmosphere.
 

ram360

Founding Member
Oct 19, 2002
2,162
1
59
Pennsylvania
Nov 13, 2005
#19
  • Nov 13, 2005
  • #19
Paul Perreca said:
good tips - and we did not degree the cam, it just went right in lol - neway !
Click to expand...


ummm... you did line up the marks on the timing chain set when you put it in right???
 
S

Scorcher2005

Member
Apr 17, 2004
883
0
16
South Carolina
Nov 13, 2005
#20
  • Nov 13, 2005
  • #20
ram360 said:
ummm... you did line up the marks on the timing chain set when you put it in right???
Click to expand...



i dont think he is that stupid...
 
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