Fuel to mileage ratio
14-Apr-2010, 10:00 PM
#22
Junior Member
Thread Starter
Join Date: Mar 2010
Posts: 24
so i learned a little more about this problem today...my engine is idling too fast...as my dad says "over-idling" hence it's burning more gas...if anyone could shed some details on this issue that would be appreciated...
16-Apr-2010, 01:34 PM
#23
Senior Member
Join Date: Dec 2007
Posts: 356
16-Apr-2010, 01:36 PM
#24
Senior Member
Join Date: Dec 2007
Posts: 356
or this:
23.7.3 Idle Speed Too High
This seems to be one of the more common problems with the idle control system. Since the PGMFI is a speed/density fuel injection system, any additional air will cause the idle to increase. Some of the sources of additional air could be:
The second most common problem is that the throttle plate is not shut. The PGMFI system is designed to run with the throttle shut and all the air that enters the engine at idle bypassing the throttle plate.
The first thing to check for is a tight throttle cable. This is fairly common, especially on Civics. Make sure the cable has slack when the car is at idle.
If the cable is not too tight, but you suspect the throttle is being held open, check the throttle stop screw. The throttle has an external stop that keeps the throttle blade from actually hitting the bore of the throttle body. It is set at the factory and should never need setting.
Image 23-9 shows a typical throttle stop screw on a multi port injection system and a dual point injection system. The screws are usually hard to
find since you should not be adjusting on them. Look and see if the yellow
paint has been broken. It is not uncommon to find that somebody has used this screw to set the idle.
Honda does not offer an adjustment procedure for this screw since it is a factory setting. If the throttle stop needs setting simply unscrew it until the throttle is resting against the bore. Then turn the stop screw in until it starts moving the throttle. Go an additional 1/2 turn or so.
23.7.3 Idle Speed Too High
This seems to be one of the more common problems with the idle control system. Since the PGMFI is a speed/density fuel injection system, any additional air will cause the idle to increase. Some of the sources of additional air could be:
- Intake manifold to cylinder head vacuum leaks
- IAC valve not closing down
- Base idle speed set too high
- Throttle blade not closing completely
- Vacuum leaks from vacuum lines
- Vacuum leak from a vacuum operated component
- Fast idle thermovalve not closing (VXs do NOT have a FITV, so this will not be a cause for fluctuating idle on a VX)
The second most common problem is that the throttle plate is not shut. The PGMFI system is designed to run with the throttle shut and all the air that enters the engine at idle bypassing the throttle plate.
The first thing to check for is a tight throttle cable. This is fairly common, especially on Civics. Make sure the cable has slack when the car is at idle.
If the cable is not too tight, but you suspect the throttle is being held open, check the throttle stop screw. The throttle has an external stop that keeps the throttle blade from actually hitting the bore of the throttle body. It is set at the factory and should never need setting.
Image 23-9 shows a typical throttle stop screw on a multi port injection system and a dual point injection system. The screws are usually hard to
find since you should not be adjusting on them. Look and see if the yellow
paint has been broken. It is not uncommon to find that somebody has used this screw to set the idle.
Honda does not offer an adjustment procedure for this screw since it is a factory setting. If the throttle stop needs setting simply unscrew it until the throttle is resting against the bore. Then turn the stop screw in until it starts moving the throttle. Go an additional 1/2 turn or so.
16-Apr-2010, 01:46 PM
#30
Junior Member
Thread Starter
Join Date: Mar 2010
Posts: 24
yea its 98...and my dad could hear it so can i...its idling too hard...and my mechanic said there's no iac valve unless my dad didnt hear me right when i told him to tell the mechanic its IAC...he probably told him something other than IAC...
16-Apr-2010, 02:42 PM
#38
Senior Member
Join Date: Mar 2010
Location: Sauga
Posts: 396
cat makes a huge difference in gas mileage,
with my lude, i got about 140km with half tank thats close to 300+ on full tank which cost me about 65$ full tank LOL
so yeah it does make a huge difference, you need it done anyways for emission
with my lude, i got about 140km with half tank thats close to 300+ on full tank which cost me about 65$ full tank LOL
so yeah it does make a huge difference, you need it done anyways for emission
19-Apr-2010, 01:11 PM
#40
Senior Member
Join Date: Dec 2007
Posts: 356
ok...well I know a few people who have had catalytic issues and noone has had that bad mileage...60km to half a tank? Your cat might be shot, but there is definitely something else going on...
the 60km to half tank...was it the bottom half or top half of the tank (according to the meter)?
the 60km to half tank...was it the bottom half or top half of the tank (according to the meter)?
