87 Idle
Thread Starter
Heel & Toe
Joined: Nov 2023
Posts: 24
Likes: 2
From: Pittsburgh PA
87 Idle
Hi group
My 87 idles perfectly except is a bit rough when in Drive stopped at a light.
I can put it in Neutral and it idles perfectly.
Any thoughts are greatly appreciated!
Many thanks!
My 87 idles perfectly except is a bit rough when in Drive stopped at a light.
I can put it in Neutral and it idles perfectly.
Any thoughts are greatly appreciated!
Many thanks!
Heel & Toe
Joined: Dec 2022
Posts: 19
Likes: 1
From: NY
I have an '87 as well, I had the same issue where it would do just that at a light and then sometimes idle high and want to kind of take off, and then go really low like it was going to stall. When put in N yes it idles more normal. Even when putting it in reverse the RPMs would drop too low. Mine so far, turned out to be the IAC - idle air control valve. Had my tech replace it, & checked out all the vacuum lines to make sure none were leaking. It has fixed the problem and never ran better. From what I've learned this is pretty common.
Heel & Toe
Joined: Dec 2022
Posts: 19
Likes: 1
From: NY
I have an '87 as well, I had the same issue where it would do just that at a light and then sometimes idle high and want to kind of take off, and then go really low like it was going to stall. When put in N yes it idles more normal. Even when putting it in reverse the RPMs would drop too low. Mine so far, turned out to be the IAC - idle air control valve. Had my tech replace it, & checked out all the vacuum lines to make sure none were leaking. It has fixed the problem and never ran better. From what I've learned this is pretty common.
Thread Starter
Heel & Toe
Joined: Nov 2023
Posts: 24
Likes: 2
From: Pittsburgh PA
I have an '87 as well, I had the same issue where it would do just that at a light and then sometimes idle high and want to kind of take off, and then go really low like it was going to stall. When put in N yes it idles more normal. Even when putting it in reverse the RPMs would drop too low. Mine so far, turned out to be the IAC - idle air control valve. Had my tech replace it, & checked out all the vacuum lines to make sure none were leaking. It has fixed the problem and never ran better. From what I've learned this is pretty common.
Ive put the IAC on the list!
Much appreciated!
Instructor
Joined: Feb 2021
Posts: 117
Likes: 23
I agree with @C4fetish, I replaced the IAC valve on my 87 and have never had an idle problem since. When you go to replace the part, definitely be gentle with all the vacuum lines. I learned the hard way…
Thread Starter
Heel & Toe
Joined: Nov 2023
Posts: 24
Likes: 2
From: Pittsburgh PA
I agree with @C4fetish, I replaced the IAC valve on my 87 and have never had an idle problem since. When you go to replace the part, definitely be gentle with all the vacuum lines. I learned the hard way…
Thank you so much! It’s definitely on the short list.
Quick question- I’ve been doing a little research on replacing these and see something about adjustments / resetting after new one installed.
Any thoughts?
Instructor
Joined: Feb 2021
Posts: 117
Likes: 23
Only thing i can think of “adjusting” after install is the TV cable when you put the throttle body back on. the valve os located under the TB so it’s pretty hard to get to without removing. adjusting the cable is simple and takes 10 seconds though. just do a quick search on how to do it.
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