I have seen velocity stacks with mechanical fuel injection utilizing methanol build pounds of ice around them all the way across the intake valley and up to the valve covers on V8 ICE's. At the same time the headers are red hot. Strange to see but with the volume of fuel air being injected/inducted is a pretty efficient form of air conditioning I suppose.
Throttle body icing? Anyone?
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Never had it happen. Out of my personal vehicles I've only had EFI on 3. My current 2005 Silverado, a 2000 cavalier I only owned for 3 months and a 332k mile 89 Caprice with TBI....my coldest start ever was with that car, -33c/-27f...it started immediately and ran fine the 1 your drive to school that day. None of the other vehicles at my girlfriend's house started that day (98 Subaru and 99 f150, some year of Suzuki Grand Vitara).
I had carb icing once on my 86 Caprice because I had the air cleaner lid flipped, so the heat riser wasn't doing anything. It was at least minus 20 and I was going over 70mph on the highway when it started to surge. As soon as I got off the highway it went back to normal.
I had carb icing once on my 86 Caprice because I had the air cleaner lid flipped, so the heat riser wasn't doing anything. It was at least minus 20 and I was going over 70mph on the highway when it started to surge. As soon as I got off the highway it went back to normal.
There are a fair amount of Ford throttle bodies where the number supercedes to a number that eliminates the hose ports. They usually come with instructions on looping the hoses together.
Carb and throttle body injection get cold from the fuel evap and can ice up, port injection not likely. Carter bbd 2 barrel can ice up. The idle air bleeds and run very rich. The solution was carb heat all the time in the winter.
Rod.
Rod.
Carb and throttle body injection get cold from the fuel evap and can ice up, port injection not likely. Carter bbd 2 barrel can ice up the idle air bleeds and run very rich. The solution was carb heat all the time in the winter.
Rod
Rod
That's one of them. Commander Ferraday with the reverse panda tricompax watch. Either a Breitling or a Heuer. Probably a Heuer Autavia.
Not sure if I have ever encountered icing. I used to have a cold running issue with my Trailblazer but it was erratic to trace to say the least. If you thawed it out in a warm shop, it would clear up. But other times temperature meant nothing.
One morning the buses were not running so we had to drive the 14 miles to town. I think ambient in our yard was about -38C. During the drive, the ambient dropped into the 40s. All the windows began to frost up like in that Day After Tomorrow movie.
One morning the buses were not running so we had to drive the 14 miles to town. I think ambient in our yard was about -38C. During the drive, the ambient dropped into the 40s. All the windows began to frost up like in that Day After Tomorrow movie.
I'm reasonably sure that in our area you can remove those coolant hoses and the only difference will be less potential for coolant leaks.
Ethanol gas actually helps to keep the fuel dry. It's like running dry gas in your car all the time. So have not had a throttle body freeze in a long time. Probably depends a lot on the humidity in the air mostly. Colorado is very dry. Here in the East we often have very wet conditions even when the overall air temperature is below freezing. Driving on a winter highway is often like being in a cloud with all the spray kicked up by vehicles, and if the temperature is close to freezing that moist air is getting sucked into your engine via the throttle body.
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This is an interesting point I never considered. I wonder if 10% ethanol is enough to make a difference? Probably?
edit: isn't HEET basically ethanol? Or am I confused?
I didn't even know this was ever an issue!
I've heard of carburettor icing up due to fuel evaporation having a refrigerant effect, but I never knew it could happen to throttle bodies in port or direct injection cars!
I've heard of carburettor icing up due to fuel evaporation having a refrigerant effect, but I never knew it could happen to throttle bodies in port or direct injection cars!
Blown alcohol engines experience this. Apparently it's only if you run a magnesium or aluminum injector hat, the carbon fiber ones don't have the same issues.
They spray deicer on the blades right before the car stages.
They spray deicer on the blades right before the car stages.
Moisture in the fuel is probably mostly a problem on older throttle body injection systems, though I imagine anything that brings moisture into the engine can cause problems. Some will make its way into the oil, and some moisture might come back to the throttle body via the pcv. Bottom line for me is they put those heating hoses on the throttle body for a reason.
I was doing underhood testing on my Gen Coupe 2L turbo when I first got it. One point was before and after the throttle body intake air temp. As long as there is vacuum behind the throttle plate there is considerable pressure drop. The more vacuum the bigger the difference.
So this is really an issue when you are just above freezing with humid air as you will get a 3-5F drop as it looses pressure caused by the throttle plate.
So this is really an issue when you are just above freezing with humid air as you will get a 3-5F drop as it looses pressure caused by the throttle plate.
I remember several times when I was a kid in the 90s, we had fuel lines freeze up. The worst culprit was our 1990 ford Taurus that was only about 4 years old at the time. There was a number of days that it wouldn't start and the 79 impala had to get everyone to work.
The only good thing about ethanol is that this problem seems to have vanished. The downside is you can't store fuel for more than a couple of months without risk of trouble.
I removed the loop on my G37, less leakage sources. No need for it in S.FL
There will be on a throttle body injected FI car.
And carbureted old tech.
Still what percentage of liquid alcohol is there at the throttle plate under vacuum? The vacuum would lower the flash point and it would all be atomized to start with. The alcohol would be the first to flash off in vapor.
Ethanol fuel helps to remove the water from the gas system since you are running it all year-round. Just like using dry gas. That means there is no water in the fuel to freeze in the throttle body (if it has throttle body injection) or the carb. In the "old days" before widespread use of ethanol gas I used to have this problem on various cars, including some fi ones.
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