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idles (barely) but won't rev at all???

  • Thread starter Thread starter jadedinpa
  • Start date Start date Apr 28, 2004
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jadedinpa

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Aug 2, 2002
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lancaster, pa
Apr 28, 2004
#1
  • Apr 28, 2004
  • #1
my 86 5.0 coupe is acting up. idles (barely)- sounds like it's running on 5 or 6 cyls. when i press the throttle it acts like it wants to shut off. it won't rev, it just stays at idle. replaced TPS, TFI, cap, rotor, plugs. reset computer, no change.

any suggestions?
 

ECU5.0

Banned
Jan 10, 2004
1,803
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0
raleigh, nc
Apr 28, 2004
#2
  • Apr 28, 2004
  • #2
im sure you did it with all the other things you replaced but the only thing that comes to mind is a new coil. it could also be bad fuel injectors....did you check all of those. if youve replaced everything else than that would be next culprit
 

88stangmangt

Active Member
Nov 25, 2003
2,332
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Stafford,VA
Apr 28, 2004
#3
  • Apr 28, 2004
  • #3
ooh boy since it is a 86 it should be F.I sound like it isnt geting much fuel i would try there is it still the 86 fuel pump? if so you have got lucky it lasted this long.
 

jadedinpa

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Aug 2, 2002
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Apr 28, 2004
#4
  • Apr 28, 2004
  • #4
tried a different coil, no change.
 

jadedinpa

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Aug 2, 2002
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Apr 28, 2004
#5
  • Apr 28, 2004
  • #5
fuel pump was replaced not long before i bought the car.
 

ECU5.0

Banned
Jan 10, 2004
1,803
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raleigh, nc
Apr 28, 2004
#6
  • Apr 28, 2004
  • #6
whoops...didnt see it was an 86...my bad....
 

88stangmangt

Active Member
Nov 25, 2003
2,332
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Stafford,VA
Apr 28, 2004
#7
  • Apr 28, 2004
  • #7
i would still check to see what the F/p is.
 

jadedinpa

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Aug 2, 2002
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lancaster, pa
Apr 29, 2004
#8
  • Apr 29, 2004
  • #8
88stangmangt said:
i would still check to see what the F/p is.
Click to expand...

it's on my to-do list.
 

Mike86Stang

Advanced Member
Apr 11, 2000
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Red Lion, PA
Apr 29, 2004
#9
  • Apr 29, 2004
  • #9
I had the same problem when I left my MAF disconnected but I dunno if you converted to mass air or not. SOoooo... I'd say check for vac. leaks, or try some starter fluid through the trottle body to see if it's fuel related (A/F ratio)

Mike
 

jadedinpa

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Aug 2, 2002
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Apr 29, 2004
#10
  • Apr 29, 2004
  • #10
speed density i'm not going mass air (staying mostly stock)

i've heard that speed density cars are very dependant on vacuum, but i don't HEAR any vacuum leaks ( not to say there aren't any, there very well could be ) so i'm not sure what's up. i still have to do a fuel pressure test and a compression test, but first need to get the tools to do so. i'm learning as i go, and when it breaks it's a great opportunity to learn something lol
 

jadedinpa

Founding Member
Aug 2, 2002
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lancaster, pa
May 1, 2004
#11
  • May 1, 2004
  • #11
replaced the fuel filter. no change. ttt
 

93tealstang

Founding Member
Jan 24, 2002
1,242
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McSherrystown/Hanover Pennsylvania
May 1, 2004
#12
  • May 1, 2004
  • #12
Maybe you could try pulling codes just to see if anything shows up.
 
G

gold73fastback

New Member
Jul 30, 2003
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Michigan
May 2, 2004
#13
  • May 2, 2004
  • #13
I had the same problem with my car, which is carburated.
Somehow oil was getting inside my distributor cap (bad seal on the shaft?) and spraying a mist around in there, I think it was causing the spark to go to ground.

also, check the positive wire on ur coil to make sure it's getting 12 V. if u don't have a voltmeter, connect a jumper wire from the positive battery terminal to the positive side of the coil and see if that helps.
 

jadedinpa

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Aug 2, 2002
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May 2, 2004
#14
  • May 2, 2004
  • #14
i just got a code reader, i'm going to see what that reveals. beyond that, right now i'm leaning towards clogged cats....
 
S

shorty1993

New Member
Apr 16, 2004
212
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Gadsden, AL
May 2, 2004
#15
  • May 2, 2004
  • #15
has the motor been down. my boys camaro did the same exact same thing that you are describing, timing was 180 out. just a thought, distributor gear
 

jadedinpa

Founding Member
Aug 2, 2002
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lancaster, pa
May 2, 2004
#16
  • May 2, 2004
  • #16
dizzy gear looks fine. i do need to check the timing.....
 
M

MatthewP

Founding Member
Dec 7, 2001
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Calgary, Alberta
May 2, 2004
#17
  • May 2, 2004
  • #17
It sounds like a timing problem to me. Make sure you pull the short plug when checking base timing.

-Matthew
 

jadedinpa

Founding Member
Aug 2, 2002
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lancaster, pa
May 4, 2004
#18
  • May 4, 2004
  • #18
UPDATE!!!!

i ran the thing long enough to get the drivers side cat to glow BRIGHT RED. methinks it's clogged. can i get a hallelujah?
 

jadedinpa

Founding Member
Aug 2, 2002
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lancaster, pa
May 16, 2004
#19
  • May 16, 2004
  • #19
update of my update...... the cats weren't clogged. the pip module in the dizzy was bad. swapped out the dizzy and it's running like a champ!
 

sixty9boss302

Founding Member
Jun 27, 2001
234
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0
Pittsburgh PA or Rochester NY
May 17, 2004
#20
  • May 17, 2004
  • #20
jadedinpa - Can you tell me the process to swap the PIP module? It seems like you just got a whole new dizzy instead of just a new PIP. Let me know cuz i think this coulld be my problem also.
 
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