Bucking under 2 grand with vortech

Warbird19

Founding Member

Sep 27, 2001

742

0

16

Washington, Federal Way

Jan 25, 2006

#1

• Jan 25, 2006

• #1

Well the car works awesome besides a low rpm bucking. Its weird its like the car just stalls at part throttle under 2 grand? any ideas? its really annoying to deal with. the Dyno Tuner said the mass air sensor need to be farther away from the blower. So i moved it about a foot farther away. Any help would be great! thanks Guys

 

L

LXracerGuy

New Member

Nov 3, 2005

30

0

0

Jan 25, 2006

#2

• Jan 25, 2006

• #2

Almost sounds like a tuning issue now to me especially with your mass air so far away from the blower.

 

Scooby5.0Doo

That's the fastest $400 car out there

Jan 9, 2003

833

0

0

beaverton

Jan 25, 2006

#3

• Jan 25, 2006

• #3

stalls like you turned the key off? i know its a long shot but i had a car with a dead spot in the tps that caused a silimalr problem cuz they always had the tps in that range so that part fryed but the rest was ok

 

ddonaca351

Active Member

Dec 1, 2002

2,055

1

48

Camas Washington

Jan 26, 2006

#4

• Jan 26, 2006

• #4

We need a slogan like "should-a-had-a-v8" only something like shoulda had a chung-o, or shoulda had a jeff...

But seriously it does sound like a tuning issue, clocking the maf might help, but if youve already moved it.... I know mine (n/a) bucks at low rpm with too much timing, but that is neither here nor there. (na vs blown)

Call Chung, he might be able to help.

Dave-

 

wicked93

5 Year Member

Nov 2, 2003

480

18

28

Winona Ohio

Jan 26, 2006

#5

• Jan 26, 2006

• #5

sounds like a fuel issue, what fuel pump are you running, injector size and fuel pres regulator is your fmu got the correct disc those are the things I would look into. also about your maf you can change the rotation of the maf and that will change the tune I would start with the maf level. I had some of the same issues at first so I hope this helps

 

Warbird19

Founding Member

Sep 27, 2001

742

0

16

Washington, Federal Way

Jan 26, 2006

#6

• Jan 26, 2006

• #6

the car has a C&L 80mm mass air, 42# injectors, AFPR, 255lph Walbro intake. The car runs like a champ when driving above 2 grand. Also below 2 grand when i open the throttle up more it works fine! Sucks cause when im trying to start out in first i have to rev the thing pretty good to get going. If its below 2 grand the thing fall all over itself and pops and crap. Im wondering if its too low on fuel or somthing. The car has been tuned by blood enterpise. I really want to take it to chung but thats a hell of a drive. Also Blood burnt me a custom chip for the car and they have a mustang dyno. So i dont know what im going to do. thanks for the help. Anything else?

 

8

86bluecobra

Advanced Member

Dec 20, 2004

4,265

12

69

B.C. Canada

Jan 26, 2006

#7

• Jan 26, 2006

• #7

my car used to buck under 2 grand aswell but i think it was when i had 2.73 gears switched to 3.73 and no longer have the problem. i noticed you have lower gears (3.73's) so i guess it is a tuning issue with you. maybe your cam doesn't like under 2 grand?

 

gospeedgo

Banned

Aug 14, 2003

978

0

0

Gresham, OR

Jan 26, 2006

#8

• Jan 26, 2006

• #8

I dont diagnose cars online, WAY to many variables. No to mention the "cooks in the kitchen" thing. But one thing that hasnt been brought up yet is: Did it just start acting up or has it been that way since the tune was done? You will be looking for different things depending on if it has always done this or not.

 

Warbird19

Founding Member

Sep 27, 2001

742

0

16

Washington, Federal Way

Jan 26, 2006

#9

• Jan 26, 2006

• #9

yeah it did it before the tune, i dont think as bad though. The car has a steeda #19 cam in it. The tuner sugested i get a 114 overlap to help with detonation.

 

M

mpette

New Member

Jul 29, 2003

11

0

1

Jan 26, 2006

#10

• Jan 26, 2006

• #10

I have just installed an vortech on my '91 GT and have a similiar problem. It is easy to stall just off idle and is difficult to start. Had Chung look at it and he slightly leaned the mixture at idle which has helped. He just burned a chip for it so it was easy for him to make this change. You might have him look at it, he can probably help.

 

Lazer2KGT

Founding Member

Jan 8, 2002

1,275

0

36

Sumner WA

Jan 26, 2006

#11

• Jan 26, 2006

• #11

Does the car have a EGR valve still on it? Try capping it if it does. See if your bucking stops. I know my car is the newer ECC version, but when I swapped in my 4V into a 2K gt I got bucking at around 2K RPM, car ran fine otherwise. I capped my EGR and the bucking went away. Could be a O2 sensor as well, hard to dignose online.
Scott

 

Warbird19

Founding Member

Sep 27, 2001

742

0

16

Washington, Federal Way

Jan 26, 2006

#12

• Jan 26, 2006

• #12

thanks for all the help guys, the car has no emmisions stuff on it.