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84 prelude...1.8l

I have posted previously on this vehicle and I have had some “success”. The car will run with the help of starting fluid but will only stay running if the engine is kept at 2500 rpms or higher. If you let off the gas, it will bog out and die. Starting it requires another shot of starting fluid and a foot on the gas. Any suggestions?

Check the fuel line pressure. Post back with the results.

You had stated earlier that this car had been sitting for years but apparently did not want to get into the carburetor disassembly end of things.

Offhand, it sounds like the carburetor has sludged up and needs to be gone through. Other possibilities could be a large vacuum leak or a fault with the anti-diesel solenoid on the carburetor.
The best way to check the solenoid is to turn the key to the run position and then disconnect and reconnect the wire connector. You should hear the solenoid click each time.

However, if the carburetor idle circuit is crudded up the anti-diesel solenoid is irrelevant until the carb is fixed.

I was unaware of the history. When opening a new post on a subject that’s been posted before, a quick overview would help. Some of us are old and have poor memories.

I guess im going to start pulling the carbs off. I looked for a vacuum leak and didnt find any. Im pretty sure I would have heard a large leak. Can you tell me where the anti-diesel solenoid is located? The fact that the cleaning I was able to do at least got it running some makes me pretty sure there is more gunk in the carb. may go with the weber replacement set up but wanted to exhaust all options before I dropped the money for it. Have to make sure thats the problem.

If you can find the plug covering the idle A/F mixture screw, remove it, very gently screw it in, counting the turns, until it stops. Do not force this screw, at the first sign of stopping, stop, should be around 1.5 turns. Remember this, then screw the screw all the way out. Spray carb cleaner into the hole and clean the tip of the screw, Then screw it back in until it stops, than back out the number of turns from the first step. Often this is all that is needed.

Tay123, this car has only one carb, and it is a complex and mean bugger. This car had Honda’s CVCC engine, and the carb is a three barrel special design that also has a BUNCH of vacuum lines running off of it. I would tread very lightly working on this carb. But, for as long as it has been sitting, the carb would need to be disassembled and cleaned thoroughly, as @ok4450 mentioned. Not enough fuel is traveling through the carb to keep the engine running.

A second though is to replace this carb with a Weber conversion. The Weber carb is a lot simpler, easy to disassemble and clean, and very easy to tune. I did this to my '84 Honda Prelude and managed to keep it running for another 5 years. I found this kit at an Ebay shop, but there are others who sell these. I know it is listed for a Honda Accord, but it is the same exact engine as your Prelude.

Go to 3 Geez forum (by and for 3rd generation Honda cars). They have a post there where an owner did the weber conversion, step by step, with picture and total cost. Google 3 Geez.com then go to the technical page and search for weber carb conversion. It’s a cool read for anybody but it seems like a must for you. Good luck! Rocketman

Remember the floats!

I pulled the carbs off, removed the float bowls and found they where nasty inside.The floats where empty so im thinking they are working correctly. The jets that have a valve on them ( works like a schrader valve) where plugged and not moving. cleaned them and freed the spring loaded valves. cleaned all the fuel ports and what ever else I could find and re-installed everything. Still has the same concern. no change at all. Runs at 2500 to 3000 rpms. Anything below that it falls on its face and dies. I did notice as the rpms drop it feels like it has a mis-fire. The plugs are new but the wires,cap and rotors arent. I wonder if there are several problems.

High rpms would demand the most fuel so i think I can eliminate fuel to the carbs as a concern.I dont know if there is a idle control valve of some kind on this vehicle. Would the vehicle at least try to idle or start with a mis-fire? Does anyone know what the switch is in the air filter housing that has 2 vacuum lines going to it from the bottom of the air filter housing? The fuel delivery system to the carbs is weird. It seems to fill one bowl and then spill over to the second carb bowl.

Just checking but have you changed the fuel filters? There are two of them, a metal one in the engine compartment and a plastic one by the fuel tank near the left rear wheel well.

When you pulled the carbs, did you do a full disassemble, soak, and ensure all ports were cleared and clean? It sounds like the idle circuits are still clogged up. I’d count that towards a valiant effort, but futile. The engine feeling like a misfire as it stalls is classic fuel starvation.

I still hold to my recommendation to replace these carbs. Especially now that we know how bad a condition these are in.

Did you pull that idle A/F mixture screw yet? This affects the A/F ratio up to about 2500 RPM.

I remember when the tri-carb Prelude came out, thinking “this is a right mess that won’t be around long”.
A friend got one because he liked my '81 Accord.
Once the aluminum alloy in those tiny idle passages corrodes the show’s over.
Carb cleaner can clear out petroleum crud, but not aluminum oxide.
I put a Weber on my Accord, along with a non-CVCC head, for a performance boost.