Part number 36450-PR7-A01 is no longer made. Can anyone advise if their is a replacement I can buy somewhere. I've tried cleaning mine with no success. My 94 Auto still idles like crap in Park at operating temp, runs like a champ though.
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Looking for an Idle Air Control Valve
- Thread starter El-Cojonico
- Start date
I don't believe the IAC goes bad all that often. I would conduct additional testing.
However, there is one on Amazon and Amayama.com shows them in stock.
However, there is one on Amazon and Amayama.com shows them in stock.
As Drew said, you can get them from Honda Japan via Amayama
Did you try letting the car run and squirting brake cleaner through the intake tube? This should clear up some gunk. Be sure to have someone in the driver seat rev it a little as you squirt. Also, do not overspray as engine will cut out.
I actually have a new throttle body from SOS. My erratic idle only happens when warm and in park. I'm thinking of taking the intake manifold out, cleaning it and putting in new gaskets. I do have 133k miles.
When you replaced the TB did you go through the base idle speed setting procedure in the service manual? The first step in that process is to set an idle speed with the EACV disconnected. If you can't complete that first step successfully that pretty much suggests that the EACV is not your problem. You would then need to figure out why you can't complete the first step. If you can't get the idle speed low enough, that might be an indication that you have an air leak someplace downstream of the throttle body.
If the TB is new, presumably it is clean. What happens downstream of the TB does not really influence idle control (short of incorrect valve clearances & timing and fouled spark plugs and the like which can make control difficult). I don't think that cleaning the intake manifold will yield an improvement in idle control although a really grungy IAT can mess up the fueling calculation; but, that usually manifests itself as mixture error codes and high fuel consumption. The exception to this might be if you have a high idle speed when trying to set the base idle indicating an air leak. In this case taking apart the manifold and replacing the gaskets might resolve the leak; however, that is a fairly big 'might'.
The EACV is electronically controlled; but, there are no electronics inside the EACV. Electrically its a dumb-ass simple pulse width controlled solenoid attached to a more sophisticated mechanical valve to control air flow. Honda does not provide a test value for the solenoid resistance; however, if you test the coil resistance and it is not zero or infinity and the resistance between the coil and EACV metal case is infinity, then electrically it is probably OK. As a last, last, last resort you can try soaking the mechanical parts of the valve in xylene, toluene or acetone. However, if there are rubber seals inside the valve you need to know what type of rubber since these solvents can bring a quick end to the wrong type of rubber (acetone and Viton don't play nice).
Thanks Old Guy, Something may have been lost in the translation..... The car starts and gets up to normal operating temp. perfectly. The problem occurs after driving for a while. When I put the car in Park. It begins to "Ping pong" between 400 rpm and about 1500 rpm. Otherwise she runs perfect. Again, Only happens when hot and in Park.
Nothing lost in translation.
When the engine is cold engine speed is controlled by the fast idle valve which is separate from the EACV. The fast idle valve is non electric. It is warmed by the coolant and when cold admits enough air to create a really fast idle. As the engine warms the fast idle closes off and engine speed drops to the point where the EACV assumes control. That is why you can have OK cold idle and bad warm idle.
My point about the intake manifold was that all that stuff on the downstream side of the throttle body is mostly irrelevant to fine idle control. So, don't go yanking the manifold apart with the expectation that it will fix your idle problem. That is a low probability outcome.
My point about setting the base idle speed was that if you can't set the base idle speed correctly, you have problems other than or in addition to the EACV. If you can set the base idle, then you may have a sticky idle valve. However, if it idles smoothly in neutral and only ping pongs in Park, that suggests the EACV is working, at least in neutral. In that case, the problem is likely with the inputs to the idle control in the ECU.
Normally I dislike diagnosis by substitution; however, the EACV is not hugely expensive and if Amayama has it, go for it. If replacement fixes the problem, two thumbs up. However, I am thinking the problem is elsewhere.
When the engine is cold engine speed is controlled by the fast idle valve which is separate from the EACV. The fast idle valve is non electric. It is warmed by the coolant and when cold admits enough air to create a really fast idle. As the engine warms the fast idle closes off and engine speed drops to the point where the EACV assumes control. That is why you can have OK cold idle and bad warm idle.
My point about the intake manifold was that all that stuff on the downstream side of the throttle body is mostly irrelevant to fine idle control. So, don't go yanking the manifold apart with the expectation that it will fix your idle problem. That is a low probability outcome.
My point about setting the base idle speed was that if you can't set the base idle speed correctly, you have problems other than or in addition to the EACV. If you can set the base idle, then you may have a sticky idle valve. However, if it idles smoothly in neutral and only ping pongs in Park, that suggests the EACV is working, at least in neutral. In that case, the problem is likely with the inputs to the idle control in the ECU.
Normally I dislike diagnosis by substitution; however, the EACV is not hugely expensive and if Amayama has it, go for it. If replacement fixes the problem, two thumbs up. However, I am thinking the problem is elsewhere.
Thanks, Old Guy. I will reset the idle according to the manual and go from there. Reason I wanted to remove the intake manifold was because I removed a top square looking piece on the manifold when I had the injectors cleaned and it was full of carbon deposit and possibly other contaminants. I assume the rest of the manifold may need a good cleaning. 133k miles is a lot of miles.
If you do the base idle set-up on your own do not use the dash tach to measure the engine speed. It will not be sufficiently accurate. I would have said especially on an older NSX; but, by now all na1 and na2 NSXs qualify as old. Use the test loop or test point in the engine compartment with an external test tach to get an accurate reading.
Acetone doesn’t play nice with anything, does it?
Whatever happened to Seafoam? When I had my TL-s it seemed like any problem could be cured by foaming the intake and adding a bottle of liquid into the tank.
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>Acetone doesn’t play nice with anything, does it?
The container I believe.
The container I believe.
Gents, removed the intake manifold and did a complete cleaning. After 133k miles there was tons of gunk, oil and sludge in the manifold. I removed all the idling valves and sensors, including the EGR. I didn't polish or grind anything but I did leave everything clean and installed new gaskets. The car is idling really well. Super steady at about 800-900 RPM. I'd recommend anyone who is over 100k miles to consider doing this. Its not difficult at all and the gaskets are cheap. it just takes a lot of elbow grease.
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