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Choke question, please respond.

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Old 12-12-03, 12:15 PM
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Choke question, please respond.

now i dont know if fuel injected cars have chokes i would assume they have some kind of choke mechanism. but i think if there is a choke that it is screwed up on mine. because my motor will not start when it is cold and that is the same thing that my sisters car does and it is because the choke is sticking. is there such a thing as a choke on my 88 TII or what part serves as a choke?
Old 12-12-03, 12:21 PM
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the efi cars dont have a choke they just run richer when the engine is cold. on a t2 you should be looking for vacuum leaks even small ones will cause starting problems
Old 12-12-03, 12:41 PM
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ok well that makes sense. the thing is it will start just fine if it is above 55 degrees farenheit but if it is any colder i have to either crank it for 5-10 minutes or push start it....that doesnt sound like a vacuum leak to me because it has soo much of a pattern to it
Old 12-14-03, 11:30 AM
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i thought a choke lets more air in while it is cold and causes a more lean condition
Old 12-14-03, 11:45 AM
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The EFI gives a richer mixture when it senses a water thermo sensor temp in a given range. There is also something called the fast idle cam and thermowax that interfaces with the throttle linkage. The thermowax keeps the throttle plates open a touch more than a normal fully heated engine. As the water passes thru the thermowax gets warmed, the thermowax's piston extends and causes the fast idle cam to move along a roll pin connected to the throttle linkage. Eventually the piston extends enough for the fast idle cam to move off the roll pin. The end result of that is the throttle linkage now is fully closed as far as the throttle stop screw will allow it to go closed.

The bac also plays a part in the cold start/idle. It's duty cycle will change as the water fully warms up.

There are clear and precise instructions in the factory service manual, along with pictures, for setting the thermowax and fast idle cam.

The throttle stop screw should not be tampered with. That was set to match the airflow meter and EFI , at the factory. Your dick will drop off if you mess with it.
Old 12-14-03, 12:30 PM
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well i know for a fact that my fast idle cam and thermowax are not operating properly because i dont get the 3000 rpm start up, would this also keep it from starting while cold.
Old 12-14-03, 12:32 PM
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and why would my dick fall off if i mess with it...is it that hard to reset or something?
Old 12-14-03, 12:39 PM
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and is the water thermo sensor the thing on the bottom of the radiator?

Last edited by Rotory; 12-14-03 at 12:55 PM.
Old 12-14-03, 02:07 PM
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Originally posted by Rotory
well i know for a fact that my fast idle cam and thermowax are not operating properly because i dont get the 3000 rpm start up, would this also keep it from starting while cold.
The thermowax does not control the 3000rpm start-up. All it does is crack open the throttle slightly so the engine idles at about 900-1000rpm until it warms up.

Do not worry if you never get a 3000rpm start-up. It's bad for the engine anyway; it's only for emissions. It's controlled by the AWS solenoid and the BAC valve.
...is the water thermo sensor the thing on the bottom of the radiator?
No, the ECU's thermosensor is on the back of the water pump housing. The temp switch in the radiator's bottom tank is part of the emission controls.

Last edited by NZConvertible; 12-14-03 at 02:09 PM.
Old 12-14-03, 05:02 PM
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If you don't get the 3000rpm on start up, then look for the water temp switch at the bottom of the radiator being disconnected. That plug/plugs being disconnected will prevent the above and also effect the emissions thru the Relief solenoids actions.

One of the wires goes to ground. The other to the ECU. That wire may be open at another point other than the water temp switch. It has a connection close to the right headlight that might be pulled apart.


The idle stop screw was set at the factory using sophisticated *tools*. You don't have the *tools*
That said, there isn't a car I've owned that I have not messed with that screw. And the dick is still there. Just letting you know there is a reason that that screw leaves the factory with a bit of goo covering it. Same with the variable resistor (fun thing to mess with). Yeah, the dick will stay on ...unless your still messing around with Sally Clap down the street.
Old 12-14-03, 05:19 PM
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the thermowax, bac, AWS etc shouldn't effect starting. it'll just effect running 1 sec after it starts. (as in stall out if not working) but it should still start fine. and stay running with a bit of throttle if everything else isn't working.

what weight oil are you using? run 10w30 in the winter. and also make sure that battery is 100% charged. if you are cranking for 10 mins a day it's probably not anymore.
Old 12-14-03, 06:10 PM
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Originally posted by Rotory
i thought a choke lets more air in while it is cold and causes a more lean condition
a choke on a carburator closes the top of the carb off so it create a larger vacuum and pulls more fuel. in other words its there to richen the mixture when the engine is cold

mike
Old 12-14-03, 10:10 PM
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Originally posted by HAILERS
If you don't get the 3000rpm on start up, then look for the water temp switch at the bottom of the radiator being disconnected. That plug/plugs being disconnected will prevent the above and also effect the emissions thru the Relief solenoids actions.

One of the wires goes to ground. The other to the ECU. That wire may be open at another point other than the water temp switch. It has a connection close to the right headlight that might be pulled apart.


The idle stop screw was set at the factory using sophisticated *tools*. You don't have the *tools*
That said, there isn't a car I've owned that I have not messed with that screw. And the dick is still there. Just letting you know there is a reason that that screw leaves the factory with a bit of goo covering it. Same with the variable resistor (fun thing to mess with). Yeah, the dick will stay on ...unless your still messing around with Sally Clap down the street.
well there has been a disconnected wire im trying to track down its coming out with the oil sensor wire by the fuel pump and it is a black connector and its disconnected. could that be the water temp switch?
Old 12-14-03, 10:34 PM
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Originally posted by Rotory
and why would my dick fall off if i mess with it...is it that hard to reset or something?
Duct tape fixes everything, either that or superglue, or maybe you could do something custom with bondo and put air vents on it.

You could have Civic Dick!!
Old 12-14-03, 11:35 PM
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Originally posted by venomrx7
Duct tape fixes everything, either that or superglue, or maybe you could do something custom with bondo and put air vents on it.

You could have Civic Dick!!
gee thanks...that helps my car start when its cold!


oh and i use Castrol GTX 10-w40 in winter and 20-w50 summer

Last edited by Rotory; 12-14-03 at 11:38 PM.
Old 12-15-03, 12:29 AM
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Originally posted by Rotory
well there has been a disconnected wire im trying to track down its coming out with the oil sensor wire by the fuel pump and it is a black connector and its disconnected. could that be the water temp switch?
That would be the oil pressure sensor by the fuel filter.

But no, the temp switch is at the bottom of the radiator. I wouldn't worry about it either. If you don't have the 3000rpm start-up you're lucky. It doesn't aid engine starting at all, it just increases engine wear.

As suggested earlier, check the ECU's thermosensor on the back of the water pump housing. The instructions are in the FSM. If the ECU doesn't realise the engine's stone cold, it will be very difficult to start.
Old 12-15-03, 12:33 AM
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The oil pressure sensor has a white tab type connector, not a black one though

The black one that is around there near the fuel filter could be the connector that goes to the little itty bitty capacitor that bolts to somewhere near there.

At least i'm prettttty sure it's a condenser of some sort.


Edit: *Nevermind me, probably is the oil pressure, I just went out and had a look and both the little condenser looking thingy and the oil pressure connector both are white and connected to the same wire... Which has now made me veeerrry confused...

/me goes to look in the FSM*

Last edited by White_FC; 12-15-03 at 12:36 AM.
Old 12-15-03, 12:53 AM
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Oops, I should've been clearer. I wasn't saying what the black connector was, just correcting his terminology.

I'm not sure what that black plug's for. The harness diagrams are usually pretty helpful, but not this time.
Old 12-15-03, 01:43 AM
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Re: Choke question, please respond.

Originally posted by Rotory
now i dont know if fuel injected cars have chokes i would assume they have some kind of choke mechanism. but i think if there is a choke that it is screwed up on mine. because my motor will not start when it is cold and that is the same thing that my sisters car does and it is because the choke is sticking. is there such a thing as a choke on my 88 TII or what part serves as a choke?
it's time to check your thermostat, all these sympthoms that you've mentioned have connection....w/ thermostat problem.

that's very easy to change.

good luck.....
Old 12-15-03, 01:58 AM
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How is a thermostat going to make a cold engine hard to start?
Old 12-15-03, 02:46 AM
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About connectors that are not connected. What helps identify the usage of the plug is the color of the wire on the plug. As in black/white indicating a black wire with a white stripe. Or a yellow/red would be a yellow wire with a red stripe. Or just a green wire, which would be a .....green wire. The shape of the connector also helps. If the connector is cylindrical and has a yellow wire on it it might be for the water temp sender near the oil pressure sensor.

By the way, trust me, you want to have both wires on the water temp switch at the bottom of the radiator.

As to the question *how can the thermostat effect the cold start*......ha, easy. The thermostat sticks while you are driving. The motor overheats. The engine locks up.......trust me, it's going to be hard to start the next time you try to start the cold engine . Any more questions??????
Old 12-15-03, 04:51 AM
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Hrmm i think i remember where i got the black connector from, its tee'd into the oil pressure sender line, but its on the condenser side of the connector, the wiring harness side is white but the actual component side is black..
IIRC..

....don't hold me too that though, i've had a few bottles of McGuigan black label with my dad so i'm a little pissed.....


God it's sad im on this forum while im drunk on uni holidays... im going out to a party
Old 12-15-03, 12:14 PM
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wow you guys are great with all the responses. thanks for correcting my terminology NZ, that cleared everything up alot.

i dont think it is my thermostat guys my engine doesnt overheat or anything like HAILERS was suggesting it never gets past even half on the guage so i dont think it is overheating and locking up. my mototr still spins very freely and cranks fast but just wont catch.

and to describe the little black plug a little better for you guys....its a squarish, black, male plug with a black/black wire and it connects to something going to the front of the car on my parts car but i cant find where the female part is coming from on my parts car so i cant track it down on my new car. Everyone with me
Old 12-15-03, 06:35 PM
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.....and your Suuuuuuuuuuuuure its a black plug? not just a white one converd in oil and various other crud (like mine.. )?

The only black/black wire down there is the wire comming from the condenser (im going to keep calling it that till someone corects me, im 99% sure thats what it is..) that bolts to near the fuel filter mount.

Except it has a WHITE male squarish looking plug
It connects to the wiring harness going towards the front of the car, the female connector is a WHITE female squarish looking plug (funny that, hehe) and is on a red/yellow wire that is tee'd into the red/yellow wire for the oil pressure sensor.

-Cheers, Nathan.
Old 12-16-03, 12:15 AM
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im positive man on both my cars its black im sure


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