1991 Honda Civic STD D15 Dual Point

No CEL

I've got an idle surge that only occurs after the car is warm and I'm sitting in traffic. I'll come out in the morning and start the car up and it will idle fine. Drive to work and if I hit traffic about 15 minutes into the drive the idle with gradually get higher and eventually surge if I don't start moving again. The car is not overheating and sometimes if I blip the throttle I can control it, unless I continue to sit in traffic. It seems to get worse if I drive for extended periods then sit in traffic.

Any ideas or stuff to test?

 

Do you have enough coolant in it? have you checkEd and cleaned the IACV?

 

Oh and what about vacuum leaks, have you checked for any?

 

I will check the coolant level, but I'm pretty sure this occurred right after I filled it up initially. I will look in the the Idle air control valve.

If it were a vacuum leak wouldn't it do that even when cold. For example, when I come out in the morning and start the car it will idle perfectly fine. I would assume a vacuum leak is a vacuum leak and does not depend on engine temperature.

 

For the record, I found a pretty helpful thread.

https://honda-tech.com/forums/honda-crx-ef-civic-1988-1991-3/idle-killing-me-88-d15-3040681/

Tomorrow I am going to check the coolant level and bleed the system. I will also check the throttle cable tension. To be completely honest it feels like this could be the case due to the fact that I can blip it and sometimes help the issue. Weird that it is temperature related though.

Any input on the FITV?

 

It ended up being the throttle cable. Quick and easy fix. Thanks for the help.