2nd Generation Specific (1986-1992) 1986-1992 Discussion including performance modifications and technical support sections.
Sponsored by:

Runs like a carburated car... Help me.

Thread Tools
 
Search this Thread
 
Old 05-25-09, 10:32 PM
  #1  
It means 12A all ways^

Thread Starter
iTrader: (20)
 
12AllWays's Avatar
 
Join Date: Jul 2008
Location: Northern IN
Posts: 769
Likes: 0
Received 0 Likes on 0 Posts
IN Runs like a carburated car... Help me.

1987 turbo II has maybe 30 minutes of run time on fresh rebuild. When cold it starts up like a carburated car without the choke on... I have to flutter the pedal and keep the rpms up to keep it running after a minute or so it idles ok. Then once hot I have to hold it to the floor to get it start. I need ideas of what could be the problem. I am leaning toward the coolant temp sensor, or connector. Any ideas would be appreciated... It has no emmisions, throttle body mod done and new O2 sensor... if that makes any diference.
Thanks
Keith
Old 05-25-09, 10:49 PM
  #2  
Super Raterhater

iTrader: (6)
 
SonicRaT's Avatar
 
Join Date: Dec 2001
Location: NY, MA, MI, OR, TX, and now LA or AZ!
Posts: 10,624
Likes: 0
Received 2 Likes on 2 Posts
could be a number of things.

Vacuum leaks
Compression
Leaky/dirty injectors
Plugs
Timing
TPS/working thermowax/etc.
Old 05-25-09, 10:53 PM
  #3  
It means 12A all ways^

Thread Starter
iTrader: (20)
 
12AllWays's Avatar
 
Join Date: Jul 2008
Location: Northern IN
Posts: 769
Likes: 0
Received 0 Likes on 0 Posts
IN

I checked comression it is good, holds 15-20 psi vac at idle, injectors no leaky, and were just cleaned.

I suppose my timing could be off a little still and plugs possibly.

Coolant temp sensor??
Old 05-25-09, 11:19 PM
  #4  
Listen to King Diamond.

iTrader: (4)
 
need RX7's Avatar
 
Join Date: Dec 2006
Location: Sterling Heights, MI
Posts: 2,832
Received 6 Likes on 6 Posts
Probably has something to do with the throttle body mod. Since all the stuff you remove when doing the throttle body mod is responsible for keeping the car running when it's cold. Not sure about the hot start problem though. I have the TB mod done to one of my FCs, and the cold-start symptoms are basically exactly the same; a small amount of throttle when cranking, some light throttle modulation for the first 2-3 minutes of operation.
Old 05-26-09, 07:13 AM
  #5  
It means 12A all ways^

Thread Starter
iTrader: (20)
 
12AllWays's Avatar
 
Join Date: Jul 2008
Location: Northern IN
Posts: 769
Likes: 0
Received 0 Likes on 0 Posts
That sounds about right. I am thinking about the coolant temp sensor being bad because it seems like it runs the cold startup map on hot starts. The CTS tells the ecu that the engine is hot, if its not working it keeps running the cold map... Causing it to be to rich... Am I right?

Originally Posted by need RX7
Probably has something to do with the throttle body mod. Since all the stuff you remove when doing the throttle body mod is responsible for keeping the car running when it's cold. Not sure about the hot start problem though. I have the TB mod done to one of my FCs, and the cold-start symptoms are basically exactly the same; a small amount of throttle when cranking, some light throttle modulation for the first 2-3 minutes of operation.
Old 04-26-10, 11:27 PM
  #6  
It means 12A all ways^

Thread Starter
iTrader: (20)
 
12AllWays's Avatar
 
Join Date: Jul 2008
Location: Northern IN
Posts: 769
Likes: 0
Received 0 Likes on 0 Posts
So someone searching knows, it was the Coolant temp sensor that was giving it fits. Put a new/different one in it and all is good.
Old 04-26-10, 11:37 PM
  #7  
My job is to blow **** up

iTrader: (8)
 
lastphaseofthis's Avatar
 
Join Date: Jan 2005
Location: palmyra Indiana
Posts: 2,900
Received 3 Likes on 3 Posts
Originally Posted by 12AllWays
That sounds about right. I am thinking about the coolant temp sensor being bad because it seems like it runs the cold startup map on hot starts. The CTS tells the ecu that the engine is hot, if its not working it keeps running the cold map... Causing it to be to rich... Am I right?
Kinda but, you're backwards. with a faulty ECT sensor, the ECU uses a default value of 180 degrees and spits fuel accordingly. so when you car is cold, it's running a "hot map".
Old 04-27-10, 10:02 AM
  #8  
Rammer Jammer

iTrader: (2)
 
RTRx7's Avatar
 
Join Date: Sep 2007
Location: Atlanta, GA
Posts: 750
Likes: 0
Received 1 Like on 1 Post
Both carburetors and fcs use the pedal on the floor as a deflooding method.

Is your afm in spec?
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
trickster
2nd Generation Specific (1986-1992)
25
07-01-23 04:40 PM
Rotospectre
New Member RX-7 Technical
3
03-28-18 03:33 PM
Im faster
General Rotary Tech Support
4
08-19-15 02:57 PM
dkwasherexd
Far East Forum
1
08-17-15 11:26 AM



Quick Reply: Runs like a carburated car... Help me.



All times are GMT -5. The time now is 09:25 PM.