Then when it warmed up it had a hunting idle from 2k to 2500 rpm. All the air entering the valve flows through a hole in the center of the white insert. Either replace the gaskets or use silicone gasket sealant. If you do not hear a click and the fuel pump, then the main relay is likely to be at fault. Note that the fast-idle valve is normally open and should close gradually as the engine warms up. Remember it is not the actual relay itself that is at fault, just the soldering. Bolted on back of the intake by the firewall.
We covered a similar problem on Toyotas in January's Foreign Service column. Stick around and you'll see how easy it is to test Honda's fast-idle valve. Fill the radiator and reservoir to their limit. Also, it is pretty rare for these to go bad. If it's open even slightly, use a socket to loosen the throttle cable bracket and move the cable one notch, to relax the cable and shut the throttle plate. The engine will usually fire, run for a split second and then stall, as the remaining fuel under pressure is used up. Hi, I have a 1993 Honda Civic ex 1.
I will be going 35. Let the engine heat up. The idle on our Hondas is a tricky thing. Do you think it could be a partially clogged fuel filter? Thanks in advance for your help. Run the engine until it has reached normal operating temperature or when the radiator cooling fan activates. This unit is basically a one way valve that allows air to enter into the intake manifold past your throttle body.
When doing this the valve should click, if it doesn't, replace it. If your screw is not epoxied over try adjusting it. The problem is symptomatic and will not trigger the Check Engine light. The car should sputter and die or almost die. You can adjust the base idle by unscrewing or screwing in the Idle screw on your throttle body. This essentially creates a small vacuum leak which in turn lets the motor idle higher than normal supposed to be around 1500-2k for warming up. Then they think the car's fixed.
Through reading forums and and other internet sources I have reason to believe it may be the Fast Idle Thermo Valve. Follow our instructions on how to replace your. And only use permium 91-93. If your screw is not epoxied over try adjusting it. Especially if not used for a couple of days.
Photo 1 shows how the tapered brass tip of the air bypass valve pokes through the hole in the white insert. This article has also been viewed 177,506 times. On the underside of your hood there should be a vacuum diagram. If in doubt just replace the hose, they are cheap. Also, you will have to keep the engine speed up yourself when the car is cold. Connect the other lead to a good engine ground source. This screw allows air to bleed into the passages on the backside of your throttle body, as shown above.
If the engine is cold, you will feel a definite suction. Eventually, the tired thermowax pellet can't close the air bypass valve at all, so the engine continues surging after it's fully warmed up. Maybe they wont have to go through as much work as I did. When the engine reaches operating temperature, the valve closes, reducing the amount of air bypassing into the manifold. As the Fast Idle Valve is factory adjusted, it can be installed or removed but not recommended to be disassembled. The expanding pellet then pushes the air bypass valve upward, sealing off the hole in the center of the white plastic insert. Also, it is pretty rare for these to go bad.
Use a socket and wrench to tighten the intake manifold bolts, starting in the middle of the manifold, and working outward toward the ends. From what I have read and experienced usually small dumb things cause these problems so don't overlook anything. The Fast Idle Valve is a component whereby when faulty can cause some starting and idle-linked problems. Place your finger over the fast idle thermo port again and feel for any vacuum suction. To learn how to adjust Honda Civic idle speed, you will not need to remove anything. A process of elimination is required to narrow down a faulty fast idle thermo valve.
Maxx2018 answered 10 months ago I have a 99 civic lx. I think i need a new o2, but that was out when i got the car. This fast idle valve is usually fitted vertically and can be found bolted on the front or the back of the intake manifold dashpot. This essentially creates a small vacuum leak which in turn lets the motor idle higher than normal supposed to be around 1500-2k for warming up. The engine may reach a point where it doesn't want extra air for fast idle any longer, but the sluggish fast-idle valve is still leaking air into the manifold, increasing idle speed.