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

bad ecu???

Thread Tools
 
Search this Thread
 
Old Apr 19, 2003 | 11:50 AM
  #1  
87basemodel's Avatar
Thread Starter
Junior Member
Tenured Member 05 Years
 
Joined: Apr 2003
Posts: 22
Likes: 0
From: Allegan
Angry bad ecu???

so far ive changed both coil/igniters and still no spark when i put my voltmeter on the leading green/yellow wire as i turn it over i get nothing. i know its not the timing chain cause the crank is turning in the cas is my ecu bad and if so where is it????????
Reply
Old Apr 19, 2003 | 01:42 PM
  #2  
Icemark's Avatar
Former Moderator. RIP Icemark.
 
Joined: Apr 2001
Posts: 25,896
Likes: 24
From: Rohnert Park CA
The ECU is located under the passngers foot board (where the fire wall meets the floor).

How did you check the grn/yel??? the signal will have ground switched on and off very rapidly (typically almost an AC cycle).
Reply
Old Apr 19, 2003 | 03:54 PM
  #3  
87basemodel's Avatar
Thread Starter
Junior Member
Tenured Member 05 Years
 
Joined: Apr 2003
Posts: 22
Likes: 0
From: Allegan
yes i did check the green/yellow and there is nothing there.....
Reply
Old Apr 19, 2003 | 04:04 PM
  #4  
Icemark's Avatar
Former Moderator. RIP Icemark.
 
Joined: Apr 2001
Posts: 25,896
Likes: 24
From: Rohnert Park CA
Again how did you check it???

You would need to set your digital multi meter to AC, put the positive lead of the meter on a 12V source and the neg lead of your meter on the wire while someone cranks the car to see any signal.
Reply
Old Apr 20, 2003 | 12:02 AM
  #5  
87basemodel's Avatar
Thread Starter
Junior Member
Tenured Member 05 Years
 
Joined: Apr 2003
Posts: 22
Likes: 0
From: Allegan
i did that and still nothing so i pulled the ecu and took it apart i have a tendancy to do this neways as soon as i pulled the carpet i smelt burnt electronics found a diode was bad so i rigged a new diode in there and now im finding 2.5 volts on the trigger wire AC... but still no spark is this because it needs 5 volts?
Reply
Old Apr 20, 2003 | 12:46 AM
  #6  
Icemark's Avatar
Former Moderator. RIP Icemark.
 
Joined: Apr 2001
Posts: 25,896
Likes: 24
From: Rohnert Park CA
No, on AC volts you will read half the voltage. If it was not triggering you would not have any AC voltage.
Reply
Old Apr 20, 2003 | 11:31 AM
  #7  
87basemodel's Avatar
Thread Starter
Junior Member
Tenured Member 05 Years
 
Joined: Apr 2003
Posts: 22
Likes: 0
From: Allegan
so i am getting a trigger but still no spark also if i plugged in a standard spark plug would i see a spark plus everything on the coil tests out?????
Reply
Old Apr 20, 2003 | 11:54 AM
  #8  
Icemark's Avatar
Former Moderator. RIP Icemark.
 
Joined: Apr 2001
Posts: 25,896
Likes: 24
From: Rohnert Park CA
If the extra plug body was grounded, yes you would see a spark if you just put a spark plug at the engine end of the spark plug cable.

If your cables are bad you may not though
Reply
Old Apr 21, 2003 | 08:01 PM
  #9  
87basemodel's Avatar
Thread Starter
Junior Member
Tenured Member 05 Years
 
Joined: Apr 2003
Posts: 22
Likes: 0
From: Allegan
i ohmed my cables and got like 17000 ohms is this right?? i also noticed before i fixed the ecu i got 12 volts on the black yellow wire on the leading coil but now i get nothing??
Reply
Old Apr 21, 2003 | 08:27 PM
  #10  
Icemark's Avatar
Former Moderator. RIP Icemark.
 
Joined: Apr 2001
Posts: 25,896
Likes: 24
From: Rohnert Park CA
Well the cables should have less than 16K ohm resistance per 3.25 feet
Reply
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
SCinfidel
3rd Generation Specific (1993-2002)
4
Sep 8, 2015 05:36 PM
befarrer
Microtech
3
Aug 22, 2015 05:52 PM




All times are GMT -5. The time now is 01:16 AM.