TBI Throttle Body Injection discussion and questions. L03/CFI tech and other performance enhancements.

Stiff gas pedal

Thread Tools
 
Search this Thread
 
Old 03-25-2012, 02:18 PM
  #1  
Member
Thread Starter
iTrader: (1)
 
ricklovin93's Avatar
 
Join Date: Jul 2011
Location: Central New York
Posts: 106
Likes: 0
Received 0 Likes on 0 Posts
Car: 1988 camaro base coupe
Engine: 305 LO3
Transmission: gm 700-r4
Stiff gas pedal

Im not sure if this is in the right category but does anybody else have a very hard ga pedal, not sure if rhi just a general third gen problem or a LO3 problem, it makes it hard to drive smoothly?
Old 03-25-2012, 03:40 PM
  #2  
Supreme Member
iTrader: (5)
 
one92rs's Avatar
 
Join Date: Jan 2009
Location: league city
Posts: 2,928
Likes: 0
Received 3 Likes on 3 Posts
Car: SOLD!!!!!
Re: Stiff gas pedal

did you remove the tbi at all or remove and reinstall the tbi throttle cable,. if you put the cable on the wrong deal it will be hard. once you put it on the right part it is easy.

throttle cable--top inside
cruise control--top outside
tv cable--bottom outside.
Old 03-25-2012, 04:12 PM
  #3  
Supreme Member

iTrader: (25)
 
UnderCover89TBI's Avatar
 
Join Date: Feb 2006
Location: Manteca,California. Nor Cal.
Posts: 7,260
Likes: 0
Received 5 Likes on 5 Posts
Car: SOLD IT. Mopar guy only now.
Engine: gone
Transmission: gone
Axle/Gears: gone
Re: Stiff gas pedal

if the cable was kinked it would cause this. Did it happen all of the sudden or after working on the car? or did you just recently get the car?
Old 03-25-2012, 06:00 PM
  #4  
Member
Thread Starter
iTrader: (1)
 
ricklovin93's Avatar
 
Join Date: Jul 2011
Location: Central New York
Posts: 106
Likes: 0
Received 0 Likes on 0 Posts
Car: 1988 camaro base coupe
Engine: 305 LO3
Transmission: gm 700-r4
Re: Stiff gas pedal

I got the car last April and drive it all summer with the stiff pedal, it's a challenge, If I'm at a red light it's impossible to slow ease on the throttle it's that stiff. I have to give it a quick tap to loosen it up then I can ease on it
Old 03-25-2012, 06:42 PM
  #5  
Member

iTrader: (7)
 
pound's Avatar
 
Join Date: Dec 2005
Location: Beautiful Coastal New Jersey
Posts: 276
Likes: 0
Received 9 Likes on 5 Posts
Car: 1990 Firebird
Engine: 350 TBI
Transmission: T5
Axle/Gears: Auburn posi 3.73
Re: Stiff gas pedal

When I first got my car the po had a return spring on the throttle body that made the gas pedal pretty stiff. You should take the air cleaner off and have a look at the throttle body.
Old 03-25-2012, 07:21 PM
  #6  
Member

 
gsxrfann's Avatar
 
Join Date: Feb 2012
Location: North Carolina
Posts: 142
Likes: 0
Received 1 Like on 1 Post
Car: 88 IROC Clone
Engine: 305 TBI
Transmission: Auto
Re: Stiff gas pedal

Mine is kind of stiff too. I just thought it was normal.
Old 03-25-2012, 08:47 PM
  #7  
Member

 
J-money's Avatar
 
Join Date: Jul 2008
Location: North Carolina
Posts: 248
Likes: 0
Received 1 Like on 1 Post
Car: 92 RS camaro, 99 Z-24 cavalier
Engine: 5.0L TBI, 2.4L
Transmission: 700r4
Axle/Gears: 2.73
Re: Stiff gas pedal

Mines been somewhat stiff too as long as Ive had my car (about 7 years now I believe). Never really found out what caused it though.
Old 03-25-2012, 08:54 PM
  #8  
Supreme Member
iTrader: (5)
 
one92rs's Avatar
 
Join Date: Jan 2009
Location: league city
Posts: 2,928
Likes: 0
Received 3 Likes on 3 Posts
Car: SOLD!!!!!
Re: Stiff gas pedal

see where the throttle cable is attached to the tbi at
Old 04-03-2012, 09:49 AM
  #9  
Junior Member
 
stezhead54's Avatar
 
Join Date: Nov 2008
Location: South Fort Myers
Posts: 29
Likes: 0
Received 0 Likes on 0 Posts
Car: 89 camaro rs
Engine: 350 LT1
Transmission: 4l60
Axle/Gears: 3.42 or so.
Re: Stiff gas pedal

So i think that i've got the same problem....my pedal sticks closed and it feels like it's stiff. i have replaced my throttle body and it still didn't change anything. i was kind of curious if there was some warping in the intake manifold would the throttle body twist and hold the throttle plates closed or make them stiff? when i tighten down the throttle body they stick worse, but when i leave all of the bolts finger tight it's almost gone. Also something else i was thinking was that because our cars are so old that if the idle screw has been adjusted to bring the throttle down any that there is a groove worn in the throttle body and the throttle plates are sticking at that grove. Is there anyone who can confirm or deny any of what i'm thinking?
Old 04-04-2012, 04:24 PM
  #10  
Junior Member

 
notoriouscamaro's Avatar
 
Join Date: Dec 2010
Location: Nesconset,NY
Posts: 75
Likes: 0
Received 1 Like on 1 Post
Car: 92 RS 5 speed
Engine: 5.0L TBI
Transmission: T-5
Axle/Gears: 9 bolt rear
Re: Stiff gas pedal

My gas pedal is kind of sticky too, ive gotten used to it..but a lot people say it could be carbon buildup on the throttle plates
Old 04-19-2012, 03:31 PM
  #11  
Supreme Member
 
rough's Avatar
 
Join Date: Apr 2007
Location: St. Petersburg, FL
Posts: 1,087
Likes: 0
Received 1 Like on 1 Post
Car: 88 Camaro
Engine: 305 TBI
Transmission: 700-R4
Axle/Gears: 2.73
Re: Stiff gas pedal

WD 40 on throttle cable and oiled up under the dash makes it smoother. Must eliminate that friction with lube!!

Can pull the 3 cables off and see if they have abnormal resistance as well!!
Old 09-11-2012, 12:30 AM
  #12  
Junior Member
 
tsha6189's Avatar
 
Join Date: Sep 2012
Posts: 13
Likes: 0
Received 0 Likes on 0 Posts
Car: 92 camaro rs
Engine: 305 tbi
Transmission: t-5
Axle/Gears: 4th gen posi 3.43
Re: Stiff gas pedal

Hello, thought i would post in here instead of starting a new thread. I have a 92 rs 305 tbi and i was wondering what would cause the gas pedal to be stiff only while the car is running? it feels nice and smooth with the engine off but after you start the car it stiffens up dramatically. Thanks for the help.
Old 09-11-2012, 01:03 AM
  #13  
Supreme Member

iTrader: (1)
 
ibmtech's Avatar
 
Join Date: Oct 2005
Location: Glen Park, NY
Posts: 1,050
Likes: 0
Received 0 Likes on 0 Posts
Car: 1987 IROC-Z
Engine: TPIS II Supercharged w/Nitrous
Transmission: 700R4 Probuilt
Axle/Gears: 3:73 Richmond 12 Bolt
Re: Stiff gas pedal

As long as your springs are on the butterfly shaft and your accelerator linkage is easy moving, there shouldn't be any reason why it feels any different when running or not
Old 09-11-2012, 01:41 AM
  #14  
Junior Member
 
tsha6189's Avatar
 
Join Date: Sep 2012
Posts: 13
Likes: 0
Received 0 Likes on 0 Posts
Car: 92 camaro rs
Engine: 305 tbi
Transmission: t-5
Axle/Gears: 4th gen posi 3.43
Re: Stiff gas pedal

Thats what i thought to, It's very strange but i just confirmed it a few mins ago got in the car before starting pushed gas pedal and it felt nice and smooth like it should, started car and it immediately stiffened right up its the most stiff when you first push the pedal down and gets kinda easier the closer you get to the floor but still fairly stiff all the way through but mostly when you first press the pedal its extremely stiff.
Old 09-11-2012, 08:23 AM
  #15  
Moderator

iTrader: (1)
 
RBob's Avatar
 
Join Date: Mar 2002
Location: Chasing Electrons
Posts: 18,405
Likes: 0
Received 216 Likes on 202 Posts
Car: check
Engine: check
Transmission: check
Re: Stiff gas pedal

Originally Posted by tsha6189
Thats what i thought to, It's very strange but i just confirmed it a few mins ago got in the car before starting pushed gas pedal and it felt nice and smooth like it should, started car and it immediately stiffened right up its the most stiff when you first push the pedal down and gets kinda easier the closer you get to the floor but still fairly stiff all the way through but mostly when you first press the pedal its extremely stiff.
If the transmission is an auto disconnect the TV cable from the TB. Now start the engine and check the go-pedal effort. Do not drive the car with the TV disconnected, just check the effort.

If no change, or if a stick shift, then likely the throttle shaft and throttle shaft bores are worn.

RBob.
Old 09-11-2012, 09:36 AM
  #16  
Junior Member
 
tsha6189's Avatar
 
Join Date: Sep 2012
Posts: 13
Likes: 0
Received 0 Likes on 0 Posts
Car: 92 camaro rs
Engine: 305 tbi
Transmission: t-5
Axle/Gears: 4th gen posi 3.43
Re: Stiff gas pedal

Thanks for the reply RBob the car is a t5 manual trans and the only cable to the tb is the throttle. So you suspect that the shaft and bores are worn out? Does that mean i need to find a new tb?
Old 09-11-2012, 10:43 AM
  #17  
Moderator

iTrader: (1)
 
RBob's Avatar
 
Join Date: Mar 2002
Location: Chasing Electrons
Posts: 18,405
Likes: 0
Received 216 Likes on 202 Posts
Car: check
Engine: check
Transmission: check
Re: Stiff gas pedal

The shaft bores can be drilled out and bushed. Doing so usually allows a slightly worn shaft to be used.

You may be able to crutch it by opening the throttle blades a little. This is done via the idle stop screw. Should use a scan tool while doing this and aim for 5 - 10 steps on a warm engine with no other loads (A/C off, fan off, ...).

That can work if the blades shift from the wear and are locking up on the bore wall. Besides, TBI set ups work better with the lower IAC steps at idle.

RBob.
Old 09-11-2012, 11:00 AM
  #18  
Junior Member
 
tsha6189's Avatar
 
Join Date: Sep 2012
Posts: 13
Likes: 0
Received 0 Likes on 0 Posts
Car: 92 camaro rs
Engine: 305 tbi
Transmission: t-5
Axle/Gears: 4th gen posi 3.43
Re: Stiff gas pedal

Ok, the idle stop screw appears to be blocked by a metal plug is it removable?
Old 09-11-2012, 12:46 PM
  #19  
Moderator

iTrader: (1)
 
RBob's Avatar
 
Join Date: Mar 2002
Location: Chasing Electrons
Posts: 18,405
Likes: 0
Received 216 Likes on 202 Posts
Car: check
Engine: check
Transmission: check
Re: Stiff gas pedal

Yes, it is removable. IIRC, I would use a sharp punch or a finishing nail to put a hole in it, then twist and pry it out.

The idle stop screw is Torx, so I remove it and cut a slot in the head to use a regular screwdriver.

RBob.
Old 09-11-2012, 03:59 PM
  #20  
Junior Member
 
tsha6189's Avatar
 
Join Date: Sep 2012
Posts: 13
Likes: 0
Received 0 Likes on 0 Posts
Car: 92 camaro rs
Engine: 305 tbi
Transmission: t-5
Axle/Gears: 4th gen posi 3.43
Re: Stiff gas pedal

Ok great, thanks a bunch for your help. Also forgive my ignorance but what kind of scan tool do I need to make the adjustment?

Also, so I just drive a finishing nail anywhere into the plug and pry till it comes out?

Last edited by tsha6189; 09-11-2012 at 04:11 PM. Reason: Addition.
Old 09-12-2012, 04:14 AM
  #21  
Junior Member
 
tsha6189's Avatar
 
Join Date: Sep 2012
Posts: 13
Likes: 0
Received 0 Likes on 0 Posts
Car: 92 camaro rs
Engine: 305 tbi
Transmission: t-5
Axle/Gears: 4th gen posi 3.43
Re: Stiff gas pedal

I also noticed someone had said the cable needs to be connected to the throttle body on the top inside point but my throttle body only has provisions for an outside connection. Don't know if this has anything to do with it or not but thought it was worth mentioning.
Old 09-12-2012, 12:29 PM
  #22  
Moderator

iTrader: (1)
 
RBob's Avatar
 
Join Date: Mar 2002
Location: Chasing Electrons
Posts: 18,405
Likes: 0
Received 216 Likes on 202 Posts
Car: check
Engine: check
Transmission: check
Re: Stiff gas pedal

Originally Posted by tsha6189
Ok great, thanks a bunch for your help. Also forgive my ignorance but what kind of scan tool do I need to make the adjustment?

Also, so I just drive a finishing nail anywhere into the plug and pry till it comes out?
Something that plugs into the ALDL port so that you can see the commanded IAC steps. WinALDL and a interface cable works. WinALDL is a free PC/Laptop Windows program.

An OBD1 handheld scan tool can also be used.

The plug is thin sheet metal.

RBob.
Old 09-12-2012, 05:47 PM
  #23  
Supreme Member
iTrader: (5)
 
one92rs's Avatar
 
Join Date: Jan 2009
Location: league city
Posts: 2,928
Likes: 0
Received 3 Likes on 3 Posts
Car: SOLD!!!!!
Re: Stiff gas pedal

Originally Posted by tsha6189
I also noticed someone had said the cable needs to be connected to the throttle body on the top inside point but my throttle body only has provisions for an outside connection. Don't know if this has anything to do with it or not but thought it was worth mentioning.
it is a blurry picture. on the top inside is the throttle. the middle outside is cruise. and the bottom is the trans cable. if yours is on top it should be good. unless it is not all the way on top.
Old 09-13-2012, 11:27 AM
  #24  
TGO Supporter

iTrader: (1)
 
Ronny's Avatar
 
Join Date: Mar 2003
Location: wisconsin
Posts: 6,879
Likes: 0
Received 2 Likes on 2 Posts
Re: Stiff gas pedal

If you disconnect the throttle cable and remove spring the slop in the shaft can be determined by wiggling the shaft.

any carb shop can handle it and I believe they put in a quality bushing. Or you can mail it out. I think DCTrumpet here offers bushing service?

i forget if original GM TB even has bushing? I put a new TB unit on my car and it was silky smooth. My cable has 124K miles on it and still smooth.
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
manualbrakes.com
Brakes
63
04-09-2024 11:55 AM
GeneralIesrussi
Carburetors
5
01-20-2020 01:06 PM
camaro1185
Engine/Drivetrain/Suspension Parts for Sale
4
10-26-2015 06:51 AM
Night rider327
Interior Parts for Sale
0
09-02-2015 04:18 AM
Night rider327
Engine/Drivetrain/Suspension Parts for Sale
0
09-02-2015 04:17 AM



Quick Reply: Stiff gas pedal



All times are GMT -5. The time now is 09:29 PM.