85 Carb Problem

[NC 85 3Door]

Well, I think it's a carb problem. By the way, just stumbled upon this site and it's effing awesome!! I had an 81 and just bought an 85, both 3 dr's so I can't wait to see more.

Anyway, the 85 has run awesome for the week I've had it. I was driving it to the plant nursery this morning to get some flowers for the wife and all of the sudden it felt like the car cut off. I pulled into a parking lot and the car starts up fine but then the tachometer goes to zero and the motor cuts off. I start it back up, floor the gas and it won't go any higher than 3,000 rpm. As soon as I let off the gas, it dies again. It has to be the carb, right? That's just my uneducated guess.

Thanks for any random ideas!

[NC 85 3Door]

Well, I started it up last night and drove it for about two miles. I tried to fire it up today and it will die unless I have it floored. After a few minutes, even flooring it won't keep it running. Profanity doesn't work either. I tried.

[greentee76]

Sounds like a vacuum leak to me. When my pcv hose split it acted exactly like this.

[Ichiban]

Does it reek of gasoline? Sometimes my float sticks open, flooding out the engine at anything but full throttle. Engine also refuses to idle. Sound familiar, or no?

[NC 85 3Door]

Ir sounds more like the vaccum leak than the float. Sometimes I smell gas but not at a reeking rate. I'm gonna take her to a Honda man later this week. I can change some oil and do some breaks, but that's pretty much the limit of my expertise. Oh, did I mention it has 246,000 miles on it? Maybe it's time for a bunch of new stuff on the motor. Thank ya'll for the advice.

[NC 85 3Door]

Ok, one more shot. The last three nights, this thing has started up and driven like a champ. During the day, I can barely keep it running. This is the weirdest damned thing I've come across in all my Hondas. I feel confident I could drive it to New Jersey tonight! I have zero confidence I could fire it up tomorrow afternoon and drive it around the corner to get a six pack of cold beer.

[Ichiban]

It almost sounds like an idle or part throttle circuit is plugged. Can you try having a friend manually apply the choke (or jam it on with wire/screwdriver) and see if that changes the way it runs? I'm guessing that the choke is applying during the cool night, enriching the mixture which compensates for a plugged channel, while during the warmer day the choke opens, offering no compensation for the lack of fuel delivery.

Does the car run any differently once it has warmed up?

[NC 85 3Door]

Ok, took it to a buddy of mine who actually restores old Mini Cooper's, but he wanted to mess around with my car. Anyway, the first day I got it over there it was only 78 degrees outside so it ran great that day. More of the same the next day since it was cool. He was out of town last weekend but Monday, it was rather hot outside and he finally got it to where it wouldn't stay running without giving it gas, then it would eventually die. He noticed a diaphram or something wasn't staying open from the intake manifold when it was hot so it wasn't getting any fresh air and was choking on the hot air. He put a BB in the vacuum line to keep it open and it's run great ever since. I'm going to go pick it up tomorrow. Weird, huh? Thanks again for everyone's help. I certainly do appreciate it.

[2ndGenGuy]

Hmm interesting. Well glad you got it working. Was it the valve on the air intake that controls hot air and cold air into the carb?

[NC 85 3Door]

That was the one. Never heard of the BB trick, but he said he's been doing that for years.