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Hazwan
04-03-2007, 06:17 PM
The problem is the car would hesitate and sometime stalls when I give too much gas when its cold. Its perfectly fine when the engine is in normal operating temperature and when I leave the manual choke on.

What I understand is, my dad said the car is always like that in the last 10 years (the whole time he owned that car).

I know choke is used when starting up when the engine is cold, but our weather isn't that cold in the morning, probably middle 20 degrees celcius and I've driven other cars with manual choke where I don't even need to touch the choke and drives perfectly fine in the morning.

Carb is just rebuilt like 10,000kms back and adjusted properly according to the manual(I think).

What else could be the problem? Will wrong spark plug heat range cause this problem?

Ichiban
04-03-2007, 07:54 PM
Do you fully disengage the choke before you start driving? I know that my 82 has a 4 position choke, full, half, high idle and off. When I start the car cold, I usually pull the choke out to half, start it, then kick it on to high idle for the first 10 minutes or so of driving, or like you said, the engine will sputter and stall. This is pretty much a feature of manual choke carbs, as the electric and water controlled chokes will gradually decrease the amount of choke and high idle progressively as the car warms up. Try leaving the choke partially on until the car is warmed right up, or responding normally.

Maybe your accelerator pump is needing adjustment? My other car had a completely plugged accelerator pump circuit and it was only noticeable when the car was cold. A sudden throttle application would cause it to stall.

2ndGenGuy
04-03-2007, 10:12 PM
My car doesn't run very well when the engine is cold either. It does the same thing you're describing. It runs smooth, but doesn't like a lot of throttle. I've swapped on the Weber with the electric choke, but I'm sure it's not tuned properly. Consider it a safety feature for your engine. If you can't hog it while it's cold, you won't hurt it. Running your engine hard while it's cold can be pretty bad for it. Once it's up to operating temp though, game on!

frantik
04-04-2007, 12:11 AM
i dont know a lot bout 1geez but i've always understood that the choke is there specifically for those cold starts.. in other words that is normal... :dunno:

Hazwan
04-04-2007, 02:39 AM
Do you fully disengage the choke before you start driving? I know that my 82 has a 4 position choke, full, half, high idle and off. When I start the car cold, I usually pull the choke out to half, start it, then kick it on to high idle for the first 10 minutes or so of driving, or like you said, the engine will sputter and stall. This is pretty much a feature of manual choke carbs, as the electric and water controlled chokes will gradually decrease the amount of choke and high idle progressively as the car warms up. Try leaving the choke partially on until the car is warmed right up, or responding normally.

Maybe your accelerator pump is needing adjustment? My other car had a completely plugged accelerator pump circuit and it was only noticeable when the car was cold. A sudden throttle application would cause it to stall.

Yes I fully disengage the choke when I start driving. I rarely used it though.
I'll check the accelerator pump later.


My car doesn't run very well when the engine is cold either. It does the same thing you're describing. It runs smooth, but doesn't like a lot of throttle. I've swapped on the Weber with the electric choke, but I'm sure it's not tuned properly. Consider it a safety feature for your engine. If you can't hog it while it's cold, you won't hurt it. Running your engine hard while it's cold can be pretty bad for it. Once it's up to operating temp though, game on!

So I guess its a 'feature' with these old engines?:dunno:


i dont know a lot bout 1geez but i've always understood that the choke is there specifically for those cold starts.. in other words that is normal...

I dunno, I've driven other cars with manual choke in the morning without any problem without using the choke:confused:

Theres a lot of time where I almost get hit when I'm going out the busy intersection when the car desided to stall.. I can't wait that long to let the car warmed up properly

frantik
04-04-2007, 04:12 AM
I dunno, I've driven other cars with manual choke in the morning without any problem without using the choke

maybe cause honda was trying to reduce fuel consuption it doesn't give enough without the choke? :dunno: I agree you shouldnt have problems if it's 20+ degrees C outside

2ndGenGuy
04-04-2007, 09:38 AM
Nah it's not really a feature. I'd like to know what the deal is too. If I could get that tuned out of my car, it would be much better to drive in the mornings. I know what you mean about almost getting hit. At my old house I had to train myself to leave a ton of extra space before pulling out into the road. Scared myself a few times pulling out and having it bog...

Ichiban
04-04-2007, 03:33 PM
An engine requires a richer fuel/air mixture when cold. Whether the designers decided to do this by means of a manual or automatic choke, richer fuel maps in open loop mode, or a cold start injector, the fact remains the same; cold engines require more fuel. When you stomp on it, you are causing a drop in manifold vacuum, which in turn causes LESS fuel to be drawn out of the carburetor's jets. This causes the bog, sputter and stalling, and is why carbs have an accelerator pump, to momentarily supplement the A/F ratio until the manifold vacuum catches up enough to draw the fuel out on it's own. Since the displacement (stroke) of the accelerator pump is designed to meet the needs of a warm engine, it has no hope in keeping up with a cold engine, especially without the choke applied. Leaving the choke partially on until the engine responds normally should help the problem.

In fact, the carb on my Toyota has an auxiliary accelerator pump that is activated by a drop in vacuum, in addition to the normal accel pump. The Aux accel pump is disabled by a thermovalve once the engine warms up.

Like I said before, auto chokes and EFI systems maintain a rich fuel mixture and high idle until the engine warms up. Auto chokes remain applied some time after starting the engine, and slowly creep open. Most people I know with manual choke engines have to do this, hell, my quad, car, rototiller and gas powered dump truck all do the same thing.

2ndGenGuy
04-04-2007, 04:06 PM
An engine requires a richer fuel/air mixture when cold. Whether the designers decided to do this by means of a manual or automatic choke, richer fuel maps in open loop mode, or a cold start injector, the fact remains the same; cold engines require more fuel. When you stomp on it, you are causing a drop in manifold vacuum, which in turn causes LESS fuel to be drawn out of the carburetor's jets. This causes the bog, sputter and stalling, and is why carbs have an accelerator pump, to momentarily supplement the A/F ratio until the manifold vacuum catches up enough to draw the fuel out on it's own. Since the displacement (stroke) of the accelerator pump is designed to meet the needs of a warm engine, it has no hope in keeping up with a cold engine, especially without the choke applied. Leaving the choke partially on until the engine responds normally should help the problem.
In fact, the carb on my Toyota has an auxiliary accelerator pump that is activated by a drop in vacuum, in addition to the normal accel pump. The Aux accel pump is disabled by a thermovalve once the engine warms up.
Like I said before, auto chokes and EFI systems maintain a rich fuel mixture and high idle until the engine warms up. Auto chokes remain applied some time after starting the engine, and slowly creep open. Most people I know with manual choke engines have to do this, hell, my quad, car, rototiller and gas powered dump truck all do the same thing.

So, assuming my carb isn't broken, should I up the size of the accelerator pump jet?

Ichiban
04-04-2007, 04:24 PM
So, assuming my carb isn't broken, should I up the size of the accelerator pump jet?


Fuck no. Unless it bogs when it's hot, too. But that could be other problems. Just run with the choke partially out until the engine runs properly. I'm sure it actually says to do this in the owners manual.

2ndGenGuy
04-04-2007, 06:03 PM
Fuck no. Unless it bogs when it's hot, too. But that could be other problems. Just run with the choke partially out until the engine runs properly. I'm sure it actually says to do this in the owners manual.

I'm running an electric choke. Fully automatic, yo. And yeah it bogs for a second when I give it wide open throttle when it's warm.

offthahook
04-04-2007, 06:53 PM
Hondas are just like that. Especially when it's cold out. You basically have to let it warm up for 5 minutes or you ain't gettin' shit out of it! After my mighty carb'd Hondas warm up, they run much better. Not much to do to cheat/hack the choke. I've driven other cars that warm up quicker and run better with less warm up time. It does seem like forever waiting on the damn car to warm up and kick the RPM's down though. Even if it isn't cold out, the first start of the day (or after the whip has been sitting for awhile) seems the worst as far as warming up goes.

2ndGenGuy
04-04-2007, 07:18 PM
Whats strange about my Weber is that as the car warms up the RPMs slowly climb. After about 5 minutes or so, I will go out to my car and its idling at like 3200RPM!!! I'm like noooo! And rush out and kick down the idle. Well by then the car is definitely warmed up. I'm just trying to tune it back factory driveability. Well it would be more of a luxury than anything. Anyways, at this point I think I'm thread jacking. So I'm going to quit.

Hazwan
04-04-2007, 09:43 PM
I guess I just need to train myself to use the choke and let the car warms up before driving.. It takes more than 10mins to warm up that sucks :(

And yeah it doesn't matter if its in the cold morning or not, as long as the engine is cold. Whats making it worse we don't even have those hot air thing near the air cleaner.

HondaBoy
04-06-2007, 09:07 PM
my '87 has the 2 barrel carb on its A20. when the vacuum system started deteriorating it started to act up like stalling and what not. i've since taken most vacuum lines off and tuned the carb. when cold it sometimes will flood out causing the need of high rpms to stay running. its as if it needs more air or something to help vaporize the fuel better.

Hazwan
04-07-2007, 06:45 AM
Ha my choke knob is acting funny where it will go back to off position after few minutes of running. 'Auto off choke'?? :wtf: