Carb Clean "chokes" my engine? (rpm drop/stall)
03-05-2015, 09:46 AM
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Carb Clean "chokes" my engine? (rpm drop/stall)
Car: Honda Civic 97 si
EJ9 Hatchback
Manual Transmission
Fuel Injected
D14A4 Engine
Car both starts and runs but then intermittently stalls. More info here.
Im looking for a possible fuel delivery problem and I´ve seen guys throw carb clean down the intake to let the car run on that in addition to gasoline.
However, when I do this my engine "chokes". Massive RPM drop or complete stall.
Is there a really obvious explanation for this that I have missed? i.e. some kind of sensor/mixture-reading that cuts the fuel feed?
(sorry if this is a stupid question)
EJ9 Hatchback
Manual Transmission
Fuel Injected
D14A4 Engine
Car both starts and runs but then intermittently stalls. More info here.
Im looking for a possible fuel delivery problem and I´ve seen guys throw carb clean down the intake to let the car run on that in addition to gasoline.
However, when I do this my engine "chokes". Massive RPM drop or complete stall.
Is there a really obvious explanation for this that I have missed? i.e. some kind of sensor/mixture-reading that cuts the fuel feed?
(sorry if this is a stupid question)
03-05-2015, 09:53 AM
#2
Re: Carb Clean "chokes" my engine? (rpm drop/stall)
Carb cleaner will impact the air fuel ratio and does bog the motor down. When spraying down the intake you must raise rpm.
Carb cleaner is not like starting fluid, it's not even remotely as flammable.
It's why it is used to find vacuum leaks. If the engine bogs when spraying around hoses and such, then you know that hose is leaking as it's sucking the carb cleaner into the intake when it should be a sealed hose.
TIP: Throttle Body cleaner is better to spray down the intake so precious metal coatings of the butterfly valve aren't damaged. Carb cleaner is much harsher and can cause damage to those coatings.
Carb cleaner is not like starting fluid, it's not even remotely as flammable.
It's why it is used to find vacuum leaks. If the engine bogs when spraying around hoses and such, then you know that hose is leaking as it's sucking the carb cleaner into the intake when it should be a sealed hose.
TIP: Throttle Body cleaner is better to spray down the intake so precious metal coatings of the butterfly valve aren't damaged. Carb cleaner is much harsher and can cause damage to those coatings.
03-05-2015, 10:08 AM
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Re: Carb Clean "chokes" my engine? (rpm drop/stall)
Carb cleaner will impact the air fuel ratio and does bog the motor down. When spraying down the intake you must raise rpm.
Carb cleaner is not like starting fluid, it's not even remotely as flammable.
It's why it is used to find vacuum leaks. If the engine bogs when spraying around hoses and such, then you know that hose is leaking as it's sucking the carb cleaner into the intake when it should be a sealed hose.
TIP: Throttle Body cleaner is better to spray down the intake so precious metal coatings of the butterfly valve aren't damaged. Carb cleaner is much harsher and can cause damage to those coatings.
Carb cleaner is not like starting fluid, it's not even remotely as flammable.
It's why it is used to find vacuum leaks. If the engine bogs when spraying around hoses and such, then you know that hose is leaking as it's sucking the carb cleaner into the intake when it should be a sealed hose.
TIP: Throttle Body cleaner is better to spray down the intake so precious metal coatings of the butterfly valve aren't damaged. Carb cleaner is much harsher and can cause damage to those coatings.
I was confused by the label on my carb clean can, which alleges it to be "extremely flammable".
Also, this guy...
Would you say this rules out the lack of fuel then?
Edit: PS. I set a timestamp in the video so people dont have to wait for him to do it.
03-05-2015, 12:03 PM
#4
Re: Carb Clean "chokes" my engine? (rpm drop/stall)
It is flammable, but I suspect it has a different burn rate and is likely why it drops rpm when sprayed into a running engine.
To rule out a fuel problem you check your fuel pressure at the rail via FSM procedure. You ohm test the injectors, and you noid test the injectors. You also check the pressure regulator of the fuel rail.
If all that checks out and your spark plugs are getting wet with fuel, you can pretty much rule out fuel.
If you've been cranking the engine a lot and not firing, you may have washed the oil of the cylinder walls which will severely inhibit compression and prevent start up. The tip is to put a teaspoon or two of oil into each cylinder to seal up the pistons rings and to oil the walls again.
To rule out a fuel problem you check your fuel pressure at the rail via FSM procedure. You ohm test the injectors, and you noid test the injectors. You also check the pressure regulator of the fuel rail.
If all that checks out and your spark plugs are getting wet with fuel, you can pretty much rule out fuel.
If you've been cranking the engine a lot and not firing, you may have washed the oil of the cylinder walls which will severely inhibit compression and prevent start up. The tip is to put a teaspoon or two of oil into each cylinder to seal up the pistons rings and to oil the walls again.
03-05-2015, 10:44 PM
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Re: Carb Clean "chokes" my engine? (rpm drop/stall)
It is flammable, but I suspect it has a different burn rate and is likely why it drops rpm when sprayed into a running engine.
To rule out a fuel problem you check your fuel pressure at the rail via FSM procedure. You ohm test the injectors, and you noid test the injectors. You also check the pressure regulator of the fuel rail.
If all that checks out and your spark plugs are getting wet with fuel, you can pretty much rule out fuel.
If you've been cranking the engine a lot and not firing, you may have washed the oil of the cylinder walls which will severely inhibit compression and prevent start up. The tip is to put a teaspoon or two of oil into each cylinder to seal up the pistons rings and to oil the walls again.
To rule out a fuel problem you check your fuel pressure at the rail via FSM procedure. You ohm test the injectors, and you noid test the injectors. You also check the pressure regulator of the fuel rail.
If all that checks out and your spark plugs are getting wet with fuel, you can pretty much rule out fuel.
If you've been cranking the engine a lot and not firing, you may have washed the oil of the cylinder walls which will severely inhibit compression and prevent start up. The tip is to put a teaspoon or two of oil into each cylinder to seal up the pistons rings and to oil the walls again.
Last edited by hondacivic97si; 03-05-2015 at 11:00 PM.
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