cold starts

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Dec 10, 2001 | 07:45 PM

brown 4x4

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Joined: Jan 2001

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From: Nebraska

cold starts

I'm talking any cold start, summer or winter, my truck has never wanted to idle at first. I'll pump the accelerator a few times (way less cranks to start), she'll start right up, but I have to keep it running for about 30 sec., and then it seems like the idle speed control motor kicks in (BTW, is this adjustable?). Runs great after this. No vacuum leaks, no computer codes (11). It's got a feedback carb with EEC-IV. I've learned to live with it, but it's a pain when other people drive it. Any suggestions? Or is this the way they all are?

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1986 F-150 4x4 300 I6 NP435

Dec 11, 2001 | 07:08 AM

Bob_VT

More Turbo

Joined: May 2000

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cold starts

I drive an 84 Bronco and a 78 Bronco both carbed. I live in Vermont where cold starts are just a way of life. I have a normal routine for both engines. As soon as I sit in the seat I push the pedal all the way to the floor once to fully engage the choke plate. Turn the key and it will start every time. I usually let it warm a bit for a minute or less and I really don't have any problems. I use the same routine for summer starts too.

I have kept the electric choke systems maintained. I removed the choke flaps and even polished the shaft that the plate attaches to. I just keep the entire choke system well maintained and they have not let me down.

22 blistering degrees with a light coat of snow on the ground. Happy holidays from Vermont.

Bob

Dec 11, 2001 | 06:56 PM

brown 4x4

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From: Nebraska

cold starts

Thanks Bob, my starting routine is pretty much the same as yours. I was mainly wondering if why it wouldn't idle at first even in summer, I don't ever remember it doing that with the last carb. I realize it's not EFI, but I wouldn't think I'd have to "warm it up" even when it's warmer.

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1986 F-150 4x4 300 I6 NP435

Dec 14, 2001 | 08:28 PM

Herman

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Joined: Sep 2001

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cold starts

My 390 did that up until I found the pinhole vacuum leak that caused it. Herman

Dec 15, 2001 | 04:19 PM

Willie

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Joined: Jun 1999

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From: Oklahoma

cold starts

Most later model vehicles with EFI systems have varous sensors that are very sensitive to any false information. This usually happens for several reasons. The most common is age. With age the sensors sometimes get out of range of the factory set tolerances, which causes false signals or (incorrect) signals to the computer. Other than not working at all or broken the sensors sometimes are subjected to false signals because of carbon build-up, containation from various sources and sometimes bad or corroded connections. One of the best ways to detect a failure is to use a system analizer.

Dec 15, 2001 | 05:38 PM

brown 4x4

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From: Nebraska

cold starts

New theory just popped in my head: could my curb idle screw be set too low? This would cause it to idle rough & die until the idle speed control motor steps the idle up. Does this sound reasonable?

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1986 F-150 4x4 300 I6 NP435

Dec 16, 2001 | 03:58 AM

indy10

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Joined: Oct 2001

Posts: 46

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From: North Pole USA

cold starts

First of all, I'd be outside in shorts at 22 degrees right now. 40 below here in north pole, AK!
Back to the problem though... Usually I can adjust my choke by closing it all the way, so it has enough gas to get up to idle. Course the carb does need to be swapped out with a new one.