1st Generation Specific (1979-1985) 1979-1985 Discussion including performance modifications and technical support sections

Continues to accelerate

Thread Tools
 
Search this Thread
 
Old Mar 24, 2008 | 08:17 AM
  #1  
g8r34994's Avatar
Thread Starter
g8r34994
 
Joined: Nov 2007
Posts: 62
Likes: 0
From: Stuart, FL
FL Continues to accelerate

Hey all, I was wondering if any of you had some ideas about this. I've got an '85 GSL that didn't run when I got it. I replaced most of the ignition, cleaned up the carb a bit, etc. I'm installing the Racing Beat dual pipe exhaust soon, and after that I'm removing the rat's nest and either going to a Sterling carb or a Holley/Weber.

It runs fairly well now - idle is a little rough, i have to run it w/ the choke until it warms up or it dies at idle. It has a couple of spots when running up the tach where i can feel definite torque change in the output. I'm attributing this to the rat's nest - probably some small vacuum leaks?

The big problem is that twice now, after I've jumped on it, the car continues to accelerate when I get off of the pedal. Obviously this is a significant safety issue. The second time it happened I turned the car off while going thru 70mph (with my foot completely off the pedal!), and a few seconds later I was rewarded with a HUGE backfire. I then turned the key back to 'on' and popped the clutch and it ran normally.

I've checked the linkage, I don't see any binding whatsoever. Plus, if there was binding, why would it run normally when I restarted? Is this something that's going to be corrected w/ the carb upgrade and rat's nest removal, or do you think I have to spend my time and money fixing this first?
Reply
Old Mar 24, 2008 | 11:47 AM
  #2  
RX-7 Chris's Avatar
Rotary Freak
iTrader: (19)
 
Joined: Oct 2007
Posts: 2,014
Likes: 0
From: Colorado Springs, CO
Do you still have the cruse control?
Reply
Old Mar 24, 2008 | 11:56 AM
  #3  
g8r34994's Avatar
Thread Starter
g8r34994
 
Joined: Nov 2007
Posts: 62
Likes: 0
From: Stuart, FL
Yes - but it wasn't engaged or even on.
Reply
Old Mar 24, 2008 | 12:33 PM
  #4  
RX-7 Chris's Avatar
Rotary Freak
iTrader: (19)
 
Joined: Oct 2007
Posts: 2,014
Likes: 0
From: Colorado Springs, CO
The only other things I can think of is coldstart or AC but I don't think that could do it. I think it could be binding at times. removing the rats nest may fix the problem. I would remove everything first before you start fixing things.
Reply
Old Mar 24, 2008 | 01:06 PM
  #5  
Ovid213's Avatar
Hall Pass Needed
Tenured Member 05 Years
 
Joined: Dec 2005
Posts: 130
Likes: 0
From: Northern Arizona
Can you get the engine to do this while the car is sitting still?
If not, I would look into the cruise control, which is indexed to road speed and will not engage unless the car is moving.
If you can, then I would look into the carb. It could be a sticky throttle, it could be that your needles or butterflies are sticking, really, w/ the rat's nest intact, it could be a lot of other random **** as well (maybe dashpot sticking?). Best bet might be to just watch the carb as it happens (if you can), but be prepared to cut it off before it spins up too high.
Reply
Old Mar 24, 2008 | 01:24 PM
  #6  
TheDriver216's Avatar
Get the shovel and boots!
Tenured Member 05 Years
iTrader: (2)
 
Joined: Jan 2007
Posts: 273
Likes: 0
From: Cleveland,OH
i had my car keep accelerating once.. my hot start assist bracket got itself caught.. only brought the car to about 4k rpm though but scared teh **** outta me
Reply
Old Mar 24, 2008 | 06:05 PM
  #7  
g8r34994's Avatar
Thread Starter
g8r34994
 
Joined: Nov 2007
Posts: 62
Likes: 0
From: Stuart, FL
FL

I'll see if I can get it to do it standing still.

Thanks for the suggestions - I'll let you know if I find anything.
Reply
Old Mar 24, 2008 | 06:49 PM
  #8  
mbonner's Avatar
Senior Member
Tenured Member 10 Years
 
Joined: Aug 2005
Posts: 250
Likes: 0
From: Onanole, Manitoba Canada
Be sure to check that cruise control out, maybe you accidentally nudged the control......something like that happened to me with a RX I owned several years ago.
Mike
Reply
Old Mar 26, 2008 | 09:27 AM
  #9  
g8r34994's Avatar
Thread Starter
g8r34994
 
Joined: Nov 2007
Posts: 62
Likes: 0
From: Stuart, FL
I haven't been able to get it to do it standing still. Didn't try too hard, cuz I hate revving it up like that with no airflow except for the fan. I'm gonna disco the cruise and see if it does it on the road again.

I'll keep you updated.
Reply
Old Nov 7, 2008 | 06:00 PM
  #10  
g8r34994's Avatar
Thread Starter
g8r34994
 
Joined: Nov 2007
Posts: 62
Likes: 0
From: Stuart, FL
out of garage now ....

I promised i'd get back - sorry its been so long. The car's been garaged for awhile because of other priorities. Anyway, last weekend I got back to it, changed out coils, plugs etc and got down to give it a good tune-up (the first that I'd given it). Well, got to the dizzy and noticed that it was cranked all the way clockwise it could go - and trying to time it found out that I really needed to go further clockwise. So i pulled the dizzy and found that it was nowhere near TDC. Took a bit to get it in right, but now she purrs. So obviously the guy I got it from effed it up and I didn't even think to look at the dizzy. I guess these babies run fairly well on just the leading(?) plugs!
Reply
Old Nov 7, 2008 | 06:07 PM
  #11  
Jeezus's Avatar
Stu-Tron Get Yo Groove On
Tenured Member: 15 Years
iTrader: (5)
 
Joined: Nov 2006
Posts: 8,482
Likes: 31
From: Huntsville AL
Glad to hear it is all better

Is the accelerator stuck thing still happening?
Reply
Old Nov 7, 2008 | 06:19 PM
  #12  
g8r34994's Avatar
Thread Starter
g8r34994
 
Joined: Nov 2007
Posts: 62
Likes: 0
From: Stuart, FL
The accelerator itself never actually stuck. All I can think of is when i hit it hard the dizzy being so out of whack kept the rpm's up until the carb bowls ran dry? I'll admit I'm out of my league on 'splaining this!
Reply
Old Nov 7, 2008 | 07:09 PM
  #13  
Kentetsu's Avatar
Lives on the Forum
Tenured Member 15 Years
 
Joined: Jun 2004
Posts: 11,359
Likes: 14
From: Grand Rapids Michigan
Check the nut that holds all of the linkage on the shaft, if that is loose it can cause this. Also, check the other end of the shaft, on the front of the carb. Sometimes the OMP linkage can bind. Good luck...


.
Reply
Old Nov 7, 2008 | 08:17 PM
  #14  
bumpstart's Avatar
talking head
Tenured Member 05 Years
 
Joined: Apr 2008
Posts: 2,775
Likes: 15
From: Perth, WA, OZ
there is a known issue with the mech secondaries mod
if you leave the vac arm attached, it will go WOT, and stay there

always remove the vac pot or its arm when doing the mech secondaries mod
Reply
Old Nov 7, 2008 | 11:06 PM
  #15  
FBsliderseven's Avatar
domokun!
Tenured Member 10 Years
iTrader: (2)
 
Joined: Jan 2007
Posts: 1,063
Likes: 0
From: hawaii
most likely a stuck accelerator. or something else.
Reply
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
Einheri
Single Turbo RX-7's
14
Oct 7, 2015 12:23 PM
WyomingTII
2nd Generation Specific (1986-1992)
12
Sep 28, 2015 10:32 AM
lnlreaper
2nd Generation Specific (1986-1992)
2
Sep 27, 2015 09:59 AM
ZacMan
Build Threads
4
Sep 19, 2015 09:20 PM




All times are GMT -5. The time now is 11:16 PM.