• Mustang Forums
  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • Fox 5.0 Mustang Tech

Car bucking untill i push in clutch !!!!

  • Thread starter Thread starter lx2c6
  • Start date Start date Oct 23, 2006
L

lx2c6

New Member
Apr 6, 2005
37
0
0
Oct 23, 2006
#1
  • Oct 23, 2006
  • #1
hey fellas , i have a annoying problem thats driving me crazy , heres the skinny on my woes , quickly heres what i got ,
brand new 302
forged bottom end
forged pistons
pro comp heads 2.05/1.60
24lbs inj
accufab tb 70mm+egr
ford motorsport maf conversion kit
73mm C&L
gt-40intake
smog delete
a/c delete
190lph Fp
3:73's
FP set @ 40
timing @13
erson cam 544/544''
new plugs , wires , distributor
new flywheel , clutch 2 yrs old , 70% life ( motorsport king cobra)
stock t-5
Heres the problem as im driving at lets say anywhere under 1500 rpm's the car will buck violently ( like it does when when a newbie driver first starts out driving stick and they let the clutch out with out enough gas and it bucks back and forth untill the clutch is put back in ) thats the same characteristic that my ride is having under 1500 rpm no matter what gear i could be driving in 5th and as soon as it goes around or under 1500 and i let off the gas it will buck. as soon as i hit the gas again it goes away and if i push in the clutch it goes away , same with parking lot driving i push in the clutch and the bucking goes away . I checked codes and i do have a speed sensor code along with some emissions codes ( prolly due to no smog) , i checked the speedo gear on the cable side and it looked fine , my car is a 87 w/o cruise control im not sure what else to check PLEASE HELP . sorry for the long novel , i appreciate any help and thoughts
 

stangjunkie

New Member
Nov 15, 2004
381
0
0
Oct 23, 2006
#2
  • Oct 23, 2006
  • #2
my car does the same in every gear between 1k and 1500rpm looking for good advice
(i also have prothane motor mounts so that may attribute to alot of mine)
 

Flavadave4

Active Member
Nov 28, 2003
1,044
21
49
Utica, NY
Oct 23, 2006
#3
  • Oct 23, 2006
  • #3
i have heard of people with an aggressive cam having bucking at lower RPMs, Mine does a little but i dont drive it much under 1500rpm anyhow!
 

stangjunkie

New Member
Nov 15, 2004
381
0
0
Oct 23, 2006
#4
  • Oct 23, 2006
  • #4
I have TFS stage one but lx2c6 has a hair more aggresive cam i think
 

Flavadave4

Active Member
Nov 28, 2003
1,044
21
49
Utica, NY
Oct 23, 2006
#5
  • Oct 23, 2006
  • #5
I wasnt sure about his, just offering my thoughts
 

1FatPony

Member
Jun 5, 2005
241
0
16
Oct 23, 2006
#6
  • Oct 23, 2006
  • #6
that exact thing was happening to me a few days ago. I found out that it was because of my high idle. All I did was lower the idle and it was fine.
I had also put in a new 302.
 

mob

the guy who hits on his mom
20+ Year Stangneter
Oct 3, 2003
2,566
136
104
Dallas, TX
Oct 23, 2006
#7
  • Oct 23, 2006
  • #7
My car did this when I broke a bolt on the upper to lower intake. Had a bad vacuum leak. Fixed it and ran fine. Did the head swap, and broke another bolt in the same spot, ill be cruising at 35mph in 4th gear and itll violently start to buck until i push in the clutch, so im thinking its a vacuum leak. Get a vacuum gauge and see that you pulling enough vacuum.
 
D

Deleted member 87397

Oct 23, 2006
#8
  • Oct 23, 2006
  • #8
Sometimes that's just the tradeoff with a heavy duty cam, a lot of power and a grippy clutch. Mine does it too, but it's just the aftermarket clutch wanting more rpms in a given gear.
 

dastang2

Active Member
Dec 11, 2003
2,020
0
46
tx
Oct 23, 2006
#9
  • Oct 23, 2006
  • #9
mine does that with the f cam, nothing you can do about it except push the gas
 

ninety15.0

New Member
Mar 10, 2004
1,336
0
0
Oct 23, 2006
#10
  • Oct 23, 2006
  • #10
mine does it too...i think the only remedies are back the idle down and take some timing out of it. low end driveability goes to $h/t with HCI cars.
 

bynummustang

Seen my other Jackstand?
Jul 24, 2005
1
2
69
NC State University
Oct 23, 2006
#11
  • Oct 23, 2006
  • #11
dastang2 said:
mine does that with the f cam, nothing you can do about it except push the gas
Click to expand...


Exact same thing with me.
 
P

projectfiveo

Member
Aug 30, 2005
347
0
17
Oct 23, 2006
#12
  • Oct 23, 2006
  • #12
my buddy has a freashly built 347 that does the same thing so i will besure to tell him to set his idle down some!
 

Roland69

Sergeant Tangnet
Sep 17, 2005
2,867
3
58
Port Elgin, Ontario
Oct 23, 2006
#13
  • Oct 23, 2006
  • #13
my bone stock GT does this but not bad....just the idle drive bucking like it needs more gas pedal.
 

1FatPony

Member
Jun 5, 2005
241
0
16
Oct 23, 2006
#14
  • Oct 23, 2006
  • #14
Mine idles around 700 and I have no bucking at all.
 

vristang

15 Year Member
Mar 31, 2005
4,933
101
124
Seattle
Oct 24, 2006
#15
  • Oct 24, 2006
  • #15
You need a tune if you are not happy with this condition.

The cam and the Injector/MAF mismatch are wreaking havoc with the puter.

Either get a tune or tuner
OR
Downshift to increase your rpms.


Good Luck
jason
 
I

iwashmycar

20+ Year Stangneter
Apr 7, 2004
1,236
1
39
Columbus, Ohio
Oct 24, 2006
#16
  • Oct 24, 2006
  • #16
mine used to buck like that taking off (was like i was a nooB at drivin), mainly when the car was cold, this last weekend i put a new belt on, and as strange as it sounds, it doesnt do it anymore...odd, but im not complaining.

I had also taken my car down to the local NTB for a tire balance, and if they did somethin i dunno...probably just burnt half the clutch off...that could be it lol
 

Black1987Stang

Active Member
Aug 22, 2004
1,422
0
37
Jersey Shore
Oct 24, 2006
#17
  • Oct 24, 2006
  • #17
playing with the timing on mine fixed the bucking for me...and cleaning the maf helped out some too
 
You must log in or register to reply here.

Similar threads

Drivetrain 83’ Glx convertible C5 Trans help!
  • JacksonJared2113
  • Dec 25, 2025
  • Fox 5.0 Mustang Tech
Replies
2
Views
397
Fox 5.0 Mustang Tech Dec 26, 2025
JacksonJared2113
Engine 1990 LX 5.0L EFI Mustang Fuel Management Problems - HELP!
  • 5.0LXStanger
  • May 25, 2025
  • Fox 5.0 Mustang Tech
  • 2 3
Replies
45
Views
2K
Fox 5.0 Mustang Tech Jul 11, 2025
5.0LXStanger
F
Trouble Shooting Sudden Shift of AFR at low RPM
  • Farva_84
  • Jun 6, 2025
  • SN95 4.6L Mustang Tech
Replies
8
Views
500
SN95 4.6L Mustang Tech Jun 8, 2025
Farva_84
F
New Member with a 1992
  • Clutchfork
  • Oct 18, 2025
  • The Welcome Wagon
Replies
5
Views
308
The Welcome Wagon Oct 19, 2025
Clutchfork
Engine Surging idle only on start up
  • keel
  • Jun 18, 2024
  • Fox 5.0 Mustang Tech
  • 2
Replies
33
Views
4K
Fox 5.0 Mustang Tech Sep 14, 2025
keel
Share:
Bluesky Email Share Link
  • Mustang Forums
  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • Fox 5.0 Mustang Tech
Menu
Log in

Register

  • Forums
  • What's new
  • Media
  • Resources
  • Contact
  • Sponsor
X

Privacy & Transparency

We use cookies and similar technologies for the following purposes:

  • Personalized ads and content
  • Content measurement and audience insights

Do you accept cookies and these technologies?

X

Privacy & Transparency

We use cookies and similar technologies for the following purposes:

  • Personalized ads and content
  • Content measurement and audience insights

Do you accept cookies and these technologies?