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Problem...

  • Thread starter Thread starter nightrider50
  • Start date Start date Sep 9, 2004
N

nightrider50

Member
Aug 28, 2003
186
0
17
California
Sep 9, 2004
#1
  • Sep 9, 2004
  • #1
I just put in an HCI combo and a new fuel pump, afpr, and injectors, water pump, fan, and all new wiring. my car has a few little problems. but the biggest one is: when i am driving in gear with my foot completely off the clutch and my other foot a little bit on the gas, the car will start jerking. it feels like when you let the clutch out too fast and it hops. I'm wondering if it could be something related to the fuel system, maybe not enough fuel? has this ever happened to anyone?
 
R

red93fox

New Member
Aug 25, 2004
41
0
0
Sep 9, 2004
#2
  • Sep 9, 2004
  • #2
did you put the distributor back in right? when doing the H/C/I did you do a new timing chain? i dont think it's fuel or a clutch problem. if it were fuel your car would sputter and want to die. that's my input, but it might be something more than timing, just figured i'd throw in my 2cents
 
N

nightrider50

Member
Aug 28, 2003
186
0
17
California
Sep 9, 2004
#3
  • Sep 9, 2004
  • #3
I put in a new timing chain and i put the distributor in right as far as i know. the timing is at 14 degrees and i made marks on the distributor so i remembered how to put it back in.
 
T

TorontoJohn

New Member
Sep 8, 2004
51
1
0
Sep 9, 2004
#4
  • Sep 9, 2004
  • #4
My car does the same thing since I put a b-303 cam and performer rmp intake. I think it might have somthing to do with the cam. Seems like at low speed off the clutch the lumpyness of the cam might be the problem.
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
34
129
Sep 10, 2004
#5
  • Sep 10, 2004
  • #5
are you still SD?
 
N

Na5.0HO

New Member
May 29, 2003
342
0
0
Michigan
Sep 10, 2004
#6
  • Sep 10, 2004
  • #6
I just threw in an E303 cam and got the same jerky sensation... I assume it's the cam and lopiness...
 

5spd GT

"the 5.0 owns all"
Founding Member
Aug 7, 2002
9,516
6
99
Arkansas
Sep 10, 2004
#7
  • Sep 10, 2004
  • #7
What rpm is the symptoms showing their self at...if it is low rpms (Ex: 1300rpm and below)...it is the common low rpm bucking with an aftermarket cam most likely...mine does it (more so when it is cold)...

You've did the MAF conversion (in your sig) and you have enough fuel for sure with 30lb injectors @ 255lph fuel pump...what is your fuel pressure set at...try 39psi with vacuum off..might help it run smoother if you haven't already did it...
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
34
129
Sep 11, 2004
#8
  • Sep 11, 2004
  • #8
5spd GT said:
You've did the MAF conversion (in your sig) ...
Click to expand...
oops. thanks for pointing that out - i did not even look in what i thought was the suspension upgrades. good eyes.
 
N

nightrider50

Member
Aug 28, 2003
186
0
17
California
Sep 12, 2004
#9
  • Sep 12, 2004
  • #9
The car bucks when it is around 1200-2000rpms. fuel pressure is set at whetever the kirban afpr comes set at, (i dont have a fuel pressure gauge). the vacuum is on the afpr. u think i should take the vacuum off of it? what does that do? would a huge oil leak have anything to do with the problem? thanx for the help
 

5spd GT

"the 5.0 owns all"
Founding Member
Aug 7, 2002
9,516
6
99
Arkansas
Sep 12, 2004
#10
  • Sep 12, 2004
  • #10
My Kirban was 36psi with the vacuum disconnected I believe when I put it on (out of the box)...so I bumped up to 39psi and it ran smoother...though it may not solve your problem...

Disconnecting the vacuum line at the AFPR shouldn't cause any kind of oil leak since it is only fuel line related...

I would get a guage to know where your adjustable regulator is adjusted at ...you can get one from www.maximummotorsports.com or www.50resto.com for $40 bucks and is a VERY easy install...takes about a minute...
 

ECU5.0

Banned
Jan 10, 2004
1,803
1
0
raleigh, nc
Sep 12, 2004
#11
  • Sep 12, 2004
  • #11
you take the vacuum line off of the regulator to adjust the fuel pressure. its more than likely because of the cam like said before. and from what ive understood from reading different things on here is that the afpr only regulates pressure at WOT and the computer handles the rest...but im not sure
 
R

ratrapp

New Member
Apr 24, 2004
510
0
0
buena vista,va
Sep 12, 2004
#12
  • Sep 12, 2004
  • #12
my b303 and typhoon intake cause the same jerkiness also.you'll have to learn to drive it in different gears to keep the rpms alittle higher to help prevent this.
 
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