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  • 1965 - 1973 Classic Mustangs -General/Talk-
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Car sputtering/not running smooth

  • Thread starter Thread starter rnrjunkie
  • Start date Start date Jun 6, 2010
R

rnrjunkie

Member
May 22, 2010
54
0
6
Germany (100% USDA Grade A American!)
Jun 6, 2010
#1
  • Jun 6, 2010
  • #1
Hi,

Went out for a cruise last night with the local V8 rowdies and really wasn't satisfied with the way my Stang was running.

I put a new Edelbrock Manifold/600er Carb Combo on a few weeks back, and since then it's been sputtering a bit now and then. Here's my setup:

289/4 Speed Toploader
Pertronix I
Edelbrock Performer Manifold
600 CFM Edelbrock Carb (Manual choke is wired open at the moment)
New Fuel Pump
New Fuel Line between Pump and Carb
New Fuel Filter
Tank and Lines are 2-3 years old. Hoses are all new.

So here's the problem. If I accelerate, I have no problems at all. Also my Idle is no problem. If I am out cruising, and I let off the gas to, the car starts to "sputter" with it jerking a bit. If I step on the gas again, it goes away.

Also, when I put the manifold in I pulled the distributor to get it out of the way. Upon reinstalling, the oil pump shaft was off for some reason, and I ended up one cylinder further on the rotor than I should have been at TDC. Instead of pulling the oil pan and the oil pump to get the shaft lined up, I just moved the wires over one spot on the dist. cap to get things running. Shouldn't be a problem, but I thought I would mention it.

Thanks in advance for any help!

Andy
 

tx65coupe

Active Member
Nov 29, 1999
1,551
1
37
Jun 6, 2010
#2
  • Jun 6, 2010
  • #2
This is just a thought, but is the idle too low? Also, it could need the floats adjusted.
 
R

rnrjunkie

Member
May 22, 2010
54
0
6
Germany (100% USDA Grade A American!)
Jun 7, 2010
#3
  • Jun 7, 2010
  • #3
tx65coupe said:
This is just a thought, but is the idle too low? Also, it could need the floats adjusted.
Click to expand...

I checked the floats before putting the carb in. Do you mean the carb idle or timing? I had a friend adjust both, which he did with a vacuum gauge. Kinda thought it was funny that he didn't use a timing light. I think it ran a bit better how I had adjusted it by ear after changing parts
 

horseballz

10 Year Member
Sep 30, 2009
824
19
49
Las Vegas, NV
Jun 7, 2010
#4
  • Jun 7, 2010
  • #4
Andy,
Try backing out the mixture screws 1/8 turn at time. Sounds like it might be running just a little lean.
HTH,
Gene
 

tx65coupe

Active Member
Nov 29, 1999
1,551
1
37
Jun 8, 2010
#5
  • Jun 8, 2010
  • #5
I meant the carb idle. The timing could be off too. Use a timing light to check the timing though.
 
R

rnrjunkie

Member
May 22, 2010
54
0
6
Germany (100% USDA Grade A American!)
Jun 10, 2010
#6
  • Jun 10, 2010
  • #6
horseballz said:
Andy,
Try backing out the mixture screws 1/8 turn at time. Sounds like it might be running just a little lean.
HTH,
Gene
Click to expand...

Just did that and took it for a test drive. Not any better really...

I did manage to change the carb spacer from a 1" to a 1/2", which allowed me to get the new air filter and choke on the carb, AND close the hood.
 
R

rnrjunkie

Member
May 22, 2010
54
0
6
Germany (100% USDA Grade A American!)
Jun 10, 2010
#7
  • Jun 10, 2010
  • #7
tx65coupe said:
I meant the carb idle. The timing could be off too. Use a timing light to check the timing though.
Click to expand...

Time to borrow a timing light
 
R

rnrjunkie

Member
May 22, 2010
54
0
6
Germany (100% USDA Grade A American!)
Jun 11, 2010
#8
  • Jun 11, 2010
  • #8
Soooo...I was out cruisin and the son of a b#*%h started misfiring. Definately ignition problems, as it kept losing power all the way home.

I picked up a coil, set of plugs and plug wires and put em in. While changing the wires I found the culprit. Annoying what a difference a cheapo item can make.

The car drives like it just got a heart transplant.
 

tx65coupe

Active Member
Nov 29, 1999
1,551
1
37
Jun 12, 2010
#9
  • Jun 12, 2010
  • #9
Thats great news. I'm glad it was an easy fix. What was actually wrong?
 
R

rnrjunkie

Member
May 22, 2010
54
0
6
Germany (100% USDA Grade A American!)
Jun 12, 2010
#10
  • Jun 12, 2010
  • #10
One of the plug wires was bad. The funny thing is that it wasn't really noticeable as an ignition problem until it started misfiring. I think the break was kinda hit and miss, and that is why it was sputtering and hesitating.
 
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