High idle issues
#1
Registered!!
Thread Starter
Join Date: Oct 2014
Posts: 3
Likes: 0
Received 0 Likes
on
0 Posts
Rep Power: 0 High idle issues
Okay guys so here's the issue: my 1997 civic ex has a very high idle. Around 1500 rpms. I've cleaned the throttle body, FITV, IACV, replaced dizzy cap, rotor, and put new ngk iridiums in. I did an idle relearn after all of that and still sitting at 1500 rpms. Bought the car with the idle issue so I don't know when or why it started. Engine was rebuilt not too long before I got the car, and has a ton of aftermarket crap on it. Some include: aem cold air intake, bbk throttle body, skunk 2 intake manifold, some sort of aftermarket fuel rail(not sure of brand off top of my head), Otto racing headers, full greddy cat back exhaust, and all upgraded internals. I'm guessing it has bigger fuel injectors too. CEL was on for o2 sensor but I replaced that and now it's just on for o2 sensor heater circuit (downstream sensor(after cat)). Car is also running rich and seems to lose power at low rpms when up to full operating temp. Any suggestions are welcomed, thanks in advance!
#2
Registered!!
Join Date: Sep 2010
Location: NE oHIo
Posts: 79
Likes: 0
Received 0 Likes
on
0 Posts
Rep Power: 0 Re: High idle issues
Car is probably running rich because of bigger fuel injectors. More fuel does NOT equal more power.
Since you have done all the checking and cleaning, the only thing left is a vacuum leak causing your idle problem. Sorry, but you have to find it. Hard to do on a message board.
-SP
Since you have done all the checking and cleaning, the only thing left is a vacuum leak causing your idle problem. Sorry, but you have to find it. Hard to do on a message board.
-SP
#3
Registered!!
Thread Starter
Join Date: Oct 2014
Posts: 3
Likes: 0
Received 0 Likes
on
0 Posts
Rep Power: 0 Re: High idle issues
Yeah I'm planning on getting some stock injectors from a junkyard to see what kinda difference that makes. Looks like I'll have to head to the store, get some carb cleaner, and check all the vacuum lines.
#4
If you think a good mechanic is expensive, try hiring a bad one
Re: High idle issues
If it's idling at 1500 RPM, is it repeatedly surging too?
What's the TPS voltage reading at idle?
What's the operating temperature?
What's the TPS voltage reading at idle?
What's the operating temperature?
#5
Registered!!
Thread Starter
Join Date: Oct 2014
Posts: 3
Likes: 0
Received 0 Likes
on
0 Posts
Rep Power: 0 Re: High idle issues
It doesn't surge, it sits at a constant 1500. I'll check the tps voltage when I have time. Operating temperature is at about 1/4-3/8, warms up and cools down just as it should.
#6
If you think a good mechanic is expensive, try hiring a bad one
Re: High idle issues
Check the computer live data for coolant temp, not the gauge on the dash.
If the operating temp is too low it may be in cold fast idle mode.
If the TPS is higher than 0.50v it may have the throttle hung open for some reason.
A/M throttle body may need tweaked to close throttle blade more?
Vacuum leaks, stuck IAC,
If it does have a FITV it MUST get hot with good antifreeze flow. I've seen the little coolant hoses and metal fittings get clogged with rust and stopleak and stuff like that and cause fast idle problems.
maybe the ECM memory needs dumped (10 minute battery disconnect with cables shorted) and a relearn done?
If the operating temp is too low it may be in cold fast idle mode.
If the TPS is higher than 0.50v it may have the throttle hung open for some reason.
A/M throttle body may need tweaked to close throttle blade more?
Vacuum leaks, stuck IAC,
If it does have a FITV it MUST get hot with good antifreeze flow. I've seen the little coolant hoses and metal fittings get clogged with rust and stopleak and stuff like that and cause fast idle problems.
maybe the ECM memory needs dumped (10 minute battery disconnect with cables shorted) and a relearn done?
#7
PITA Admin
Administrator
iTrader: (1)
Join Date: Dec 2008
Location: TN
Age: 52
Posts: 14,793
Received 1,449 Likes
on
1,203 Posts
Rep Power: 339 Re: High idle issues
97 is not a 8th gen or 9th gen car, they much newer than yours.
moved!
moved!
Thread
Thread Starter
Honda Civic Forum
Replies
Last Post
Bradel26
Mechanical Problems/Vehicle Issues and Fix-it Forum
5
05-30-2015 10:24 AM
vtechcivic
Mechanical Problems/Vehicle Issues and Fix-it Forum
3
04-21-2015 06:58 PM