Underpowered?
08-10-2004, 02:02 PM
#16
Three Wheelin'
I just adjusted the accel pedal position on the weekend and in re-adjusting the throttle cable (something that I thought I had done right before) I found more slack. Well, slack isn't really the right word. Bottom line, it wasn't opening the throttle fully. Almost, but not quite. Do this one first because it is very easy and will cost you nothing to check off of the list.
.....Cameron
'91 Euro GT
.....Cameron
'91 Euro GT
08-10-2004, 02:44 PM
#17
Former Vendor
I have to agree with the consensus.
My shark with auto will not spin the wheels from a stand still, however, I also own a Grand Cherokee Ltd, both my cars are in pretty good shape and I can tell you that after a drive in the shark, the Jeep feels like it's running on 4 cyl.
Paul
My shark with auto will not spin the wheels from a stand still, however, I also own a Grand Cherokee Ltd, both my cars are in pretty good shape and I can tell you that after a drive in the shark, the Jeep feels like it's running on 4 cyl.
Paul
08-10-2004, 02:56 PM
#18
Burning Brakes
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Just to throw in my .02. My 87 S4 is in the trans shop and was ready today. I went to pick it up & told the manager I wanted to test drive the car to see if it was running the same as when I brought it in. It wasn't. I had to push the gas pedal a quarter way down to get it to move. He told me "that's normal". I said BS! 
I'm not picking up the car nor am I paying for it until it's right. I've been going back & forth for almost 2 weeks with this place. Adjust the cable like everyone has suggested. When I finally get the 928 home, i'm going to do the intake R&R too. Probably a lot of other stuff WIAT. Bill, plz keep this post updated for i'm going to follow along as well. Good luck, were both going to need it. 
I'm not picking up the car nor am I paying for it until it's right. I've been going back & forth for almost 2 weeks with this place. Adjust the cable like everyone has suggested. When I finally get the 928 home, i'm going to do the intake R&R too. Probably a lot of other stuff WIAT. Bill, plz keep this post updated for i'm going to follow along as well. Good luck, were both going to need it.
08-10-2004, 04:38 PM
#21
Three Wheelin'
Adjusting the downshift transmission linkage will help--under the right conditions (e.g., lots of throttle at zero to low speed, the transmission should start in first). There's a vacuum modulator you can swap that will give 1st gear starts, but mixed reports on using it.
If you put the car in "2," it will start from 1st gear, and downshift from 2nd to 1st at ~10mph. Personally, I find the shock load of the downshift to first to be unappealing, although I could probably adjust the little T for a smoother shift. The car should shift automatically from 1st to 2nd somewhere around 5500 RPM although some report shifting >6k, but if you quickly move the shifter from 2 to 3 back to 2, you can upshift "manually" to second at lower RPMs. If you just move it from 2 to 3, you'll shift to 2nd, and then almost immediately to 3rd, which is generally undesirable.
This topic has been covered a lot already, search for it.
If you put the car in "2," it will start from 1st gear, and downshift from 2nd to 1st at ~10mph. Personally, I find the shock load of the downshift to first to be unappealing, although I could probably adjust the little T for a smoother shift. The car should shift automatically from 1st to 2nd somewhere around 5500 RPM although some report shifting >6k, but if you quickly move the shifter from 2 to 3 back to 2, you can upshift "manually" to second at lower RPMs. If you just move it from 2 to 3, you'll shift to 2nd, and then almost immediately to 3rd, which is generally undesirable.
This topic has been covered a lot already, search for it.
08-10-2004, 10:46 PM
#24
Rocket Pilot
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87s4
just my experience, my 87 s4 5 spd. gets a consistent 5.45-5.85 0-60.without x-pipe or chips.i am told this is how it is supposed to run. never quartered the car but i am sure it would do the 13.9-or better. about that cobra. i took one from 70 t0 120 not once but 3 times on rt. 15 pa.,guy would not give up,would slow to 70 , blow his horn , and hit it. dont know about dead start though.
08-11-2004, 01:11 PM
#25
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I just adjusted the accel pedal position on the weekend and in re-adjusting the throttle cable (something that I thought I had done right before) I found more slack. Well, slack isn't really the right word. Bottom line, it wasn't opening the throttle fully. Almost, but not quite. Do this one first because it is very easy and will cost you nothing to check off of the list.
08-11-2004, 03:39 PM
#26
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While digging out the manifold, check the MAF. I had a similar condition once, and the MAF was faulty, causing the "limp home" mode, and very scary A/F ratios on the dyno. Also check the vacum lines, a loose one could also cause these issues..
08-11-2004, 07:03 PM
#27
Three Wheelin'
Re the throttle cable adjustment. Here is a simplistic, quick explanation.
I tested the length by having my son depress and hold the accelerator pedal to the floor. Uh, make sure that the engine is turned off when you do this. While he did that, I then checked the linkage on the side of the intake manifold to see if it was fully open. It was not. The throttle cable goes from the linkage into/through the firewall. If I remember correctly, the throttle cable is the inside (closest to the manifold) bottom cable of the three (or four if you have an auto) cables connected to the linkage. If you trace the cable, you will see where it goes into the firewall. There (where it goes into the firewall), you will find a plastic device that can be screwed in or out - which adjusts the cable.
Adjust and have your son (or someone) depress the accel again and re-test. Adjust as neccessary.
You should remove the air intake tube on the driver's side and the top part of the air filter assembly to access the throttle cable adjuster.
.......Cameron
'91 Euro GT
I tested the length by having my son depress and hold the accelerator pedal to the floor. Uh, make sure that the engine is turned off when you do this. While he did that, I then checked the linkage on the side of the intake manifold to see if it was fully open. It was not. The throttle cable goes from the linkage into/through the firewall. If I remember correctly, the throttle cable is the inside (closest to the manifold) bottom cable of the three (or four if you have an auto) cables connected to the linkage. If you trace the cable, you will see where it goes into the firewall. There (where it goes into the firewall), you will find a plastic device that can be screwed in or out - which adjusts the cable.
Adjust and have your son (or someone) depress the accel again and re-test. Adjust as neccessary.
You should remove the air intake tube on the driver's side and the top part of the air filter assembly to access the throttle cable adjuster.
.......Cameron
'91 Euro GT
08-11-2004, 08:13 PM
#29
Rennlist Member
Bill,
Except for a '91 GT EZK, my '88 S4 auto is stock - with not too much urging, it will downshift to whatever appropriate gear (1st included) and redline @ ~6400 in each gear if you choose to stay in: these are not 10 sec, 0-60 types of cars!
If I may add a little to Camerons post, when setting the cable lengths to the quadrant;
- place a stick between the seat front and the throttle: run the power seat ahead until the throttle closes the kickdown switch ( you can hear the 'click')
- take the linkages off the quadrant (loosen the locknuts, do not loose the locking spring bail clips). set the xmission control and cruise cables aside.
- pull the quadrant linkage back against its stop as in WOT (wide open throttle), and adjust the throttle cable ( at the ball head and at the point Cameron mentioned - the plastic nut) - and reattach so the ball just meets the socket: no slack, no tension!
EDIT: Length vs. Stroke. Here, it is important to note the difference between the two adjustments on cables with plastic adjusters: The length of the ( braided steel ) cable is determined by adjusting the brass ball head, and its lock nut - The stroke, or more correctly, the length of stroke and position of stroke is determined by positioning the sheath of the braided steel cable by the plastic adjuster. Not as complicated as it sounds - but important!
The importance of this is that in adjusting the throttle and the throttle body cable (comming up next) is that in addition to opening fully, they must also close fully when released: This may require a couple of checks by releasing the stick on the throttle pedal.
- adjust the throttle body cable by pulling the cable to open the butterfly valve against its stop, and match up against its ball stud at WOT - do not adjust this one too tightly, for the last several % of this type of valve adds nothing to its flow characteristic - but you do want to assure the WOT signal is activated - reattach!
- next, release the seat & handy stick: with the throttle closed, grab the Xmission control cable and pull tight. Adjust its length to just slide over the ball stud - again, no tension, no slop!
- reattach the cruise cable - it adjusts itself with its control box logic.
You are now set - unless there are significant outstanding items not up to par as detailed in Jim Bailey's thorough list
Snappy redline shifts to you ...
Except for a '91 GT EZK, my '88 S4 auto is stock - with not too much urging, it will downshift to whatever appropriate gear (1st included) and redline @ ~6400 in each gear if you choose to stay in: these are not 10 sec, 0-60 types of cars!
If I may add a little to Camerons post, when setting the cable lengths to the quadrant;
- place a stick between the seat front and the throttle: run the power seat ahead until the throttle closes the kickdown switch ( you can hear the 'click')
- take the linkages off the quadrant (loosen the locknuts, do not loose the locking spring bail clips). set the xmission control and cruise cables aside.
- pull the quadrant linkage back against its stop as in WOT (wide open throttle), and adjust the throttle cable ( at the ball head and at the point Cameron mentioned - the plastic nut) - and reattach so the ball just meets the socket: no slack, no tension!
EDIT: Length vs. Stroke. Here, it is important to note the difference between the two adjustments on cables with plastic adjusters: The length of the ( braided steel ) cable is determined by adjusting the brass ball head, and its lock nut - The stroke, or more correctly, the length of stroke and position of stroke is determined by positioning the sheath of the braided steel cable by the plastic adjuster. Not as complicated as it sounds - but important!
The importance of this is that in adjusting the throttle and the throttle body cable (comming up next) is that in addition to opening fully, they must also close fully when released: This may require a couple of checks by releasing the stick on the throttle pedal.
- adjust the throttle body cable by pulling the cable to open the butterfly valve against its stop, and match up against its ball stud at WOT - do not adjust this one too tightly, for the last several % of this type of valve adds nothing to its flow characteristic - but you do want to assure the WOT signal is activated - reattach!
- next, release the seat & handy stick: with the throttle closed, grab the Xmission control cable and pull tight. Adjust its length to just slide over the ball stud - again, no tension, no slop!
- reattach the cruise cable - it adjusts itself with its control box logic.
You are now set - unless there are significant outstanding items not up to par as detailed in Jim Bailey's thorough list
Snappy redline shifts to you ...
Last edited by Garth S; 08-12-2004 at 04:30 AM.
08-11-2004, 08:23 PM
#30
Drifting
Jim, does your GT spin the tires with little effort? My 91 you would have to rev it high and dump the clutch to get it to spin, otherwise it takes off rather lumberly and pulls like a freight train after that.
jason
91GT
jason
91GT