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

Binding issue GSL-SE

Thread Tools
 
Search this Thread
 
Old Apr 30, 2005 | 11:50 AM
  #1  
BigPimpin''s Avatar
Thread Starter
Rotary Freak
Tenured Member 15 Years
iTrader: (5)
 
Joined: Sep 2004
Posts: 1,583
Likes: 0
From: Hagerstown, MD
Binding issue GSL-SE

On the TB there is a little roller thing right by the throttle cable ( I'm assuming that's the fast idle cam) that is binding causing the high idle. Is that needed or can I just grind it off so they don't hit each other. Car idles fine now at 850 but when you hit the gas it sticks on that roller. What to do to correct it?
Reply
Old May 1, 2005 | 11:48 AM
  #2  
LongDuck's Avatar
84SE-EGI helpy-helperton
Tenured Member: 20 Years
Liked
Loved
Community Favorite
 
Joined: Oct 2002
Posts: 3,584
Likes: 542
From: Phoenix, AZ
That is the cold-start idle compensator cam (AKA Fast Idle Cam).

This roller is used to to keep the throttle cracked a bit more during cold starts (based on Thermowax Module) so that the car will idle a bit faster during cold starts. As you may be aware, the rotary engines don't tend to run will at low rpm's until they're warmed up, so Mazda designed this cam to catch the throttle rod until the Thermowax pellet signals that the cam can be released based on coolant temp through the coolant line coming from the back of the water pump to the TB. This coolant line is returned to the top of the rear housing.

If you grind this down, it will not work correctly to increase cold start RPM, and may cause problems with driveability in cold conditions until it warms up. When you start an SE, the pedal should go all the way to floor ONCE, let off the pedal completely, then turn key to start. This will 'set' the fast idle cam, and, when combined with the reading from the coolant temp sensor (back of WP), will increase fuel flow to provide a rich mixture to the engine.

Bypassing this stock system may not be such a good idea, unless you live in an area that never sees cold temps (below about 50F).

I would recommend trying to lube this part or find out where your TB rods are binding to fix the problem, but that's me.
Reply
Old May 1, 2005 | 07:52 PM
  #3  
BigPimpin''s Avatar
Thread Starter
Rotary Freak
Tenured Member 15 Years
iTrader: (5)
 
Joined: Sep 2004
Posts: 1,583
Likes: 0
From: Hagerstown, MD
I will check but what I see is where those two points meet the fast idle cam is not rolling freely of of the roller, it passes it when you press the throttle and sits on it when you release the throttle. I'll try lube to see if it works. I used a heavier return spring ( which still lets it go to WOT) but it still hangs up. When I first start the car idle is fine, hit the gas and it catches, pop the pedal and it drops back down. Thanks for info!
Reply
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
rgordon1979
3rd Generation Specific (1993-2002)
40
Mar 15, 2022 12:04 PM
cewrx7r1
3rd Generation Specific (1993-2002)
15
Aug 6, 2018 11:41 AM
betes
1st Generation Specific (1979-1985)
8
Sep 27, 2015 08:25 AM
Steven_McKinley
General Rotary Tech Support
12
Sep 5, 2015 10:48 AM




All times are GMT -5. The time now is 03:26 PM.