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ea82 fuel starvation when warming up


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If anyone can explain this I will be impressed. OK, I have an old sportswagon ( EA82 ) which drives perfectly when fully warmed up and when first started in the morning, but there is a stage between warm and cold that makes the car almost un-drivable.:-\ Before you ask I'm in Australia so its not exactly cold here in the mornings but its cold enough to make the choke cut in.

 

It jerks around like there is no fuel getting through although if you are very light on the gas you can drive it. It takes several minutes of gentle driving then it carry's on like normal.:)

 

I have replaced nearly all the vacume hoses and have tested all the modules attached, they all work fine. The only thing I can think of is the ' hot idle compensator ' which is some kind of vacume vent.:confused:

 

Now here is the question. Why would you want to vent all the vacume from the inlet manifold. Surely when the vent is open the air will rush into the inlet manifold and starve the engine of fuel. :headbang:

 

Unfortunately I am no where near the car and have limited access to it ( my partner won't let me touch it during the week incase it won't start in the morning - she uses it for work ).:-\

 

Any thoughts no matter how strange will be appreciated. Has anyone had this before.

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hmmm that sounds like what my roommates brat did. He drove it all winter like that before it crapped out on him. We ended up replacing the carb.

Sounds like you float is sticking shut until the car warms up all the way.

 

Perhaps a carb swap (only 4 10 mm nuts) or a carb rebuild.

 

Maybe others will chime in and help me out here.

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Hi its definately not the carb, I had that professionally rebuilt, cost me $300 AU, all jets were changed and tested all OK.

 

The problem is more precise than that.

 

It is every morning when the car is cold ( mist on the windows ). It starts and runs fine then a little while after the auto choke is off it mis-behaves badly. Then if you are gentle and keep driving very lightly without any steep hills it will come back to normal.

 

If you start the car at lunch it is fine. Problem has to be related to a warming stage. This is why I am not sure about the ' hot idle compensator ', is it possible that when the car warms this is venting all the vacume in the inlet manifold - why would you ever want to release the inlet manifold vacume.

 

Can anyone explain what ths device is supposed to do ?

 

Ohh wo is me, ohh me, ohh my.:banghead:

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If anyone can explain this I will be impressed. OK, I have an old sportswagon ( EA82 ) which drives perfectly when fully warmed up and when first started in the morning, but there is a stage between warm and cold that makes the car almost un-drivable.:-\ Before you ask I'm in Australia so its not exactly cold here in the mornings but its cold enough to make the choke cut in.

 

It jerks around like there is no fuel getting through although if you are very light on the gas you can drive it. It takes several minutes of gentle driving then it carry's on like normal.:)

 

I have replaced nearly all the vacume hoses and have tested all the modules attached, they all work fine. The only thing I can think of is the ' hot idle compensator ' which is some kind of vacume vent.:confused:

 

Now here is the question. Why would you want to vent all the vacume from the inlet manifold. Surely when the vent is open the air will rush into the inlet manifold and starve the engine of fuel. :headbang:

 

Unfortunately I am no where near the car and have limited access to it ( my partner won't let me touch it during the week incase it won't start in the morning - she uses it for work ).:-\

 

Any thoughts no matter how strange will be appreciated. Has anyone had this before.

just get an spfi swap and all your crappy carb problems will end. forever!!!:brow:
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Also, just because you had the carb rebuilt dosen't mean the mechanic didn't miss something. There are a lot of little spaces in there that are not very accessable. A used carb is not that expenssive and if no change you would have a spare. Just another thought. I had a simmilar problem w/my 86' wagon and a carb swap fixed it. $50 at wrecking yard much less than $300 au.

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Getting rid of my carb, although a nice idea isn't an option - especially now that I have had it rebuilt.

 

All the filters, including the fuel filter at the tank have been changed.

 

Fuel is good because it has been happening for several tanks and I always use decent garages ( BP etc )

 

Plugs are clean, no build up. I have changed the oil, rotor arm, leads, plugs, air filter, fuel filter and air freshner as just part of a normal service ( when I get my hands dirty I make it worth while ).

 

Plugs are a little white but not enough to make me think anything overly strange.

 

The worse thing about this is that when I get home and get in the car it will drive perfect because it isn't ice cold.

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mcs, twice this has happened to mine (EA82 Carb.) in the last fourteen years, first time nealy drove me nuts untill I replaced the fuel pump, s/h, cheap, then only last week started again as soon as the cooler mornings arrived so as a test I swaped carbys, no fix, then swaped fuel pumps again, problem fixed. The problem is is that it starts fine then runs out of fuel within a few minutes or less, then picks up and goes OK from there on in. I would definately get a s/h fuel pump and give it a whirl.. Lang

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Replacing the fuel pump does seem to be a common thought in most of the people I have talked too. However they are $200 for a genuine one and $100 for a white box - I don't like scrap yard pumps because there is no guarentee that it works.

 

I can't see it being the pump because it produces enough fuel to run the car when its cold and I can gun like a rocket when the engine has completely warmed up. I will add a glass filter at the top next to the carb, when it jumps around if it is the fuel then the chamber will be empty.

 

Its worth a go I guess. Has anyone else had temperature related problems with the pump ?

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As a general carb-type suggestion, could the choke be adjusted such that it is coming off too soon? I myself haven't seen the carb on an EA82 (all of mine are FI), but this is a general problem on emission-era carb'd engines.

 

Another possibility is a problem with the water heating of the manifold/carb.

 

Are the carburetors in the Australian market "feedback" carbs? Does your car have an O2 sensor? If so, there might be some sensor issues.

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Next time it plays up,stop motor (if it hasn't allready) lift the top of your air cleaner and depress the throttle and you will probably see that no fuel is being put in by the accelerator pump.

 

Sun Spares in Qld. are the place to go for your bits.. I think, but dont quote me, s/h pumps were , are about $30-00 or less and they are honourable to deal with... Do a Google for their web..

 

As I said , has happened twice to me in the winter and that was the cause...lang

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I havent heard of a Feedback carb in Australia, and we also never had the SPFI option, we have Carb'd, MPFI and MPFI Turbo as far as i know :drunk:

 

I was gonna suggest the filter cos i had similar problems where it would run like a hairy goat for the first 5 minutes, (later found out it was the fuel filter and the first 5 minutes of road had steep hills and thus needed more fuel)

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OK, I am going to buy a fuel pump and give it a go. I am in Sydney West ( Penrith ), does anyone know a good place to get a NEW pump. Most places I call have high pressure pumps. The manual says it only needs 20kPa (38 litre's per hour) is this right, I guess as long as the carb can stop the pressure I guess it doesn't matter if I go slightly over.

 

Thanks to everyone for their input, this is my first thread and I must say everyone has been wonderful. Its really appreciated.

 

:drunk:

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l had exactly the same problem with my Brumby except it would stop dead for 5-10 mins then fire up as though nothing was wrong, it nearly drove me nuts until l found it to be an intermittant fault with the electromagnetic fuel pump. This also happened to my sisters MY wagon, she had it looked at by just about everybody Subaru in Melbourne without success, then she bought it to me, ( didn't want to bother me, poor dear), l replaced her electromagnetic pump and presto, back to normal. This is not a rare problem and it pays to keep a spare one of these on hand as they do fail. l hope your problem turns out to be this easy.

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mc, the thing is, as you have spent so much time and money trying to fix so far without avail, a s/h pump may point out the cure, then spend the money on a new one... and keep whatever as a spare, I keep one in vehicle at all times. Let us know how things work out, for all our benifits.

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mc, the thing is, as you have spent so much time and money trying to fix so far without avail, a s/h pump may point out the cure, then spend the money on a new one... and keep whatever as a spare, I keep one in vehicle at all times. Let us know how things work out, for all our benifits.

 

I agree - i also do not like using junkyard parts, but untill you are absolutely sure you know what the problem is it would be best to try second hand parts first. Then if it fixes the problem you can get a new one.

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OK, now I looked at the fuel pump last night with the car on tick over and noticed that it was running and stopping every second, like someone was switching it on and off quickly. Is this normal, I would have expected the pump would have stayed energised once the engine was running. I am going to try forcing a 12 volt supply from the side lights when I get home that way it removes the possibility of an unreliable supply. If that doesn't work then 10 mins later I will be out spending $$$ on a pump.:banana:

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Happy days are here. I fitted the new pump last night and my lady has told me that its all OK now, she can happily waste petrol while trying to boot it up a hill in the wrong gear.

 

Thanks to everyone for their input, its really appreciated. New fuel pump cost me $60 AU and delivers 5 lb pressure.

 

:banana::banana::banana:

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