Technical help Q & A Got A technical problem with you car? Keep it in here where the techies hang out and we will try to solve it for you!!

Erratic engine idle when switching high beams

Thread Tools
 
Search this Thread
 
Old Aug 28, 2021 | 05:36 PM
  #1  
cossie2's Avatar
cossie2
Thread Starter
Regular Contributor
20 Year Member
Liked
Loved
Community Favorite
 
Joined: Nov 2004
Posts: 304
Likes: 33
From: Croatia
Default Erratic engine idle when switching high beams

Hi,
as above what could cause erratic idle/engine sputters on cossie when switching lights or high beams...Checked main earths and alternator all seems fine..
Any thoughts would be great..thanks
Reply
Old Aug 29, 2021 | 09:57 AM
  #2  
Caddyshack's Avatar
Caddyshack
10K+ Poster!!
 
Joined: Mar 2013
Posts: 10,837
Likes: 1,033
From: Guildford
Default

I would run a dedicated earth to the ECU and lights etc. To rule that out, it has to be some noise or an earth. May be worth getting the alternator checked by a specialist too.
Reply
Old Aug 29, 2021 | 01:20 PM
  #3  
cossie2's Avatar
cossie2
Thread Starter
Regular Contributor
20 Year Member
Liked
Loved
Community Favorite
 
Joined: Nov 2004
Posts: 304
Likes: 33
From: Croatia
Default

Great..thanks will try that.......alternator checks alraedy done....removed the lights relay and than switched on lights..still same..this will take some time to sort out
Reply
Old Sep 27, 2021 | 06:05 AM
  #4  
rayben's Avatar
rayben
15000
 
Joined: Mar 2015
Posts: 40
Likes: 5
From: East London
Default

Using a multimeter, check the voltage when your car is running and as you turn the high beams on.
Reply
Old Sep 27, 2021 | 04:53 PM
  #5  
cossie2's Avatar
cossie2
Thread Starter
Regular Contributor
20 Year Member
Liked
Loved
Community Favorite
 
Joined: Nov 2004
Posts: 304
Likes: 33
From: Croatia
Default

.......Thanks...it was earth issue some kind so i have routed new earth wire from engine block to ecu pins 1 and 19......all is well now.....Time for new loom i quess
Reply
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
rog
General Car Related Discussion.
5
Nov 7, 2007 02:00 PM
mpales
Ford Sierra/Sapphire/RS500 Cosworth
11
Aug 4, 2007 01:37 PM
ngary
Technical help Q & A
3
Nov 6, 2006 12:19 AM
adzbelcher
Ford Sierra/Sapphire/RS500 Cosworth
6
May 17, 2006 04:22 PM




All times are GMT. The time now is 04:00 AM.