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  • Fox 5.0 Mustang Tech

backfire's and sputters at low rpm's

  • Thread starter Thread starter casey4093
  • Start date Start date Aug 27, 2004
C

casey4093

New Member
Nov 15, 2003
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Gulfport, MS
Aug 27, 2004
#1
  • Aug 27, 2004
  • #1
I have an 87 5.0, when i first start it up sputters and will backfire and pop if i try to get on the gas to hard before it warms up, and sometimes after its already warm.

I've tried messing with the TPS, different settings of Fuel pressure, different settings of ignition timing, cleaned my mass air sensor, etc... I can't get it to quit for nothing.

It has a new IAC, new TPS set at .95v, new O2 sensors, 19lb injectors, BBK AFPR set at a steady 40psi, trick flow cam 221/225 duration .499/.510 lift, 1.90/1.60 manley stanless steal valves, trick flow springs, Ford racing 65mm throttle body, 73mm mass air, edelbrock performer intake, no cats, no egr, no smog pump, accel 300+ ignition box, Accel TFI, ford racing 9mm plug wires, Accel u-grove plugs, Accel coil, Black magic electric fan.
 

ram360

Founding Member
Oct 19, 2002
2,162
1
59
Pennsylvania
Aug 27, 2004
#2
  • Aug 27, 2004
  • #2
How's your timing?
 
S

seijirou

Founding Member
Aug 15, 2002
2,417
4
48
DFW
Aug 27, 2004
#3
  • Aug 27, 2004
  • #3
This may seem like a dumb question, but you said steady 40psi of fuel pressure? Does this mean it is 40 at idle and 40 at wot?
 
C

casey4093

New Member
Nov 15, 2003
15
0
0
Gulfport, MS
Aug 28, 2004
#4
  • Aug 28, 2004
  • #4
I started out with my timing at 10 then went up to 12 then to 14 and now 15 degrees advanced.

The fuel pressure is set at 40 with the vacumme line off
 
M

mackey

Active Member
Jan 25, 2003
1,284
1
38
Beverly, Massachusetts
Aug 28, 2004
#5
  • Aug 28, 2004
  • #5
Same problem here. ttt
 

MSM0075

Member
May 13, 2003
741
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16
Central Jersey
Aug 28, 2004
#6
  • Aug 28, 2004
  • #6
I got the same problem with my '82GT. If its not warm it makes putting noises through the exhaust.
 
C

casey4093

New Member
Nov 15, 2003
15
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Gulfport, MS
Sep 1, 2004
#7
  • Sep 1, 2004
  • #7
little help please????
 

Legendary

Founding Member
Oct 10, 2002
1,925
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City of Angels
Sep 1, 2004
#8
  • Sep 1, 2004
  • #8
I have the same problem at cold starts only. I actually asked about it here: http://forums.stangnet.com/showthread.php?t=497990

I think the gap in my plugs are too big. Started happening after the tune up.
 
R

Rerun

Founding Member
Mar 31, 2002
312
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16
South Bay, California
Sep 1, 2004
#9
  • Sep 1, 2004
  • #9
Sammmme problem, I get the sputting in the exhaust if I don't let the car warm up, like it's pissed or something. Well ****, if someone rolled me out of bed and started throwing me out the door I'd probably raise some hell too. Anyhow, I just pull over and let it warm up for a few more seconds, usually fixes it. I always thought it to be a timing problem.
 

jrichker

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Mar 10, 2000
27,512
2,813
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Dublin GA
Sep 1, 2004
#10
  • Sep 1, 2004
  • #10
Dump the codes and see what the computer says is wrong…

Here's the link to dump the computer codes with only a jumper wire or paper clip and the check engine light, or test light or voltmeter. I’ve used it for years, and it works great.

See http://www.troublecodes.net/Ford/
OR
See http://www.dalidesign.com/hbook/eectest.html for more descriptive help
OR
See http://www.mustangworks.com/articles/electronics/eec-iv_codes.html

IF your car is an 86-88 stang, you'll have to use the test lamp or voltmeter method. There is no functional check engine light on the 86-88's except possibly the Cali Mass Air cars.

Codes have different answers if the engine is running from the answers that it has when the engine isn't running. It helps a lot to know if you had the engine running when you ran the test.

Trouble codes are either 2 digit or 3 digit, there are no cars that use both 2 digit codes and 3 digit codes.

For those who are intimidated by all the wires & connections, see http://www.actron.com/product_detail.php?pid=16153 for what a typical hand scanner looks like. Normal retail price is about $30 or so at AutoZone or Walmart.
 
C

casey4093

New Member
Nov 15, 2003
15
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0
Gulfport, MS
Sep 2, 2004
#11
  • Sep 2, 2004
  • #11
I will check my codes but, I don't have a check engine light on!!!! will that make a difference in the codes?
 
S

seijirou

Founding Member
Aug 15, 2002
2,417
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DFW
Sep 2, 2004
#12
  • Sep 2, 2004
  • #12
no
 

Legendary

Founding Member
Oct 10, 2002
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City of Angels
Sep 6, 2004
#13
  • Sep 6, 2004
  • #13
I solved my problem.

http://forums.stangnet.com/showthread.php?p=4549726#post4549726
 
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