S5 NA: idle problems when engine is cold
#1
Full Member
![](/images/misc/20_year_icon.png)
Thread Starter
Join Date: Aug 2001
Location: NH
Posts: 147
Likes: 0
Received 0 Likes
on
0 Posts
S5 NA: idle problems when engine is cold
Okay, checked out the FAQ and did a search, but after 10 pages of idle posts, didn't find what I was looking for.
Basically, when my engine is cold, my car won't hold idle and just dies. I can keep it running by giving it some gas, but that's a pain. Once the engine warms up, it seems to hold idle fine.
I just replaced vacuum lines and plugs. I'm guessing a sensor is out of whack or bad, but not sure where to start...any advice?
Thanks
Bret
Basically, when my engine is cold, my car won't hold idle and just dies. I can keep it running by giving it some gas, but that's a pain. Once the engine warms up, it seems to hold idle fine.
I just replaced vacuum lines and plugs. I'm guessing a sensor is out of whack or bad, but not sure where to start...any advice?
Thanks
Bret
#3
+1. If the BAC and thermowax are gone, that's the problem.
If they have no been removed, you could be looking at a problem with the water temp sensor on the back of the water pump. Check the connector, and test the voltage at the ECU pin. Pulling codes is also a good idea: http://www.johnr.com/cpucodes.html.
If they have no been removed, you could be looking at a problem with the water temp sensor on the back of the water pump. Check the connector, and test the voltage at the ECU pin. Pulling codes is also a good idea: http://www.johnr.com/cpucodes.html.
#4
Full Member
![](/images/misc/20_year_icon.png)
Thread Starter
Join Date: Aug 2001
Location: NH
Posts: 147
Likes: 0
Received 0 Likes
on
0 Posts
The car is stocked, nothing has been removed. I will check to see if I have any codes. I'm guessing I should look further into the BAC, thermowax, and water temp sensor further? At least that gives me a start.
#6
Full Member
![](/images/misc/20_year_icon.png)
Thread Starter
Join Date: Aug 2001
Location: NH
Posts: 147
Likes: 0
Received 0 Likes
on
0 Posts
I haven't had a chance to dig into my problem further as I've been busy with other things, but hoping to work on the problem this weekend. I'll snap some picts of the components and hopefully if I solve it, post the fix.
Trending Topics
#8
Hail Dented 7
iTrader: (3)
Join Date: Sep 2010
Location: Vermont
Posts: 209
Likes: 0
Received 0 Likes
on
0 Posts
When I was setting mine, and checked it cold it read way up near 2v (actually it was 1.7x)
But once I let it warm up, it was a perfect 1v.
Thread
Thread Starter
Forum
Replies
Last Post
trickster
2nd Generation Specific (1986-1992)
25
07-01-23 04:40 PM
ncds_fc
New Member RX-7 Technical
1
08-15-15 10:06 AM