1981 f100 acceleration problems
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1981 f100 acceleration problems
well first i didn't know what to title this thread so sorry if it is a little misleading.
I have a 1981 f100 with the 4.9 300 IL 6, i just timed it and got it running nice. On Friday night i was stuck at a RR crossing so i shut off my truck waited till the train moved, after it did, I proceded and my truck was acting like it didn't want to accelerate. Well after getting up to speed of about 35MPH the 'stuttering' went away. On saturday i got up and made it out the door and the stuttering resumed. i talked to the shop foreman at work, and he suggested it was my ignition control module, said that its possible for it to go bad because the gel inside will melt which it has, so i replaced it with one around the shop (believe it or not). Still doing the same thing, i cleaned out my fuel filter, looked under the distributer cap for condensation, found nothing and still it continues...not after ive been running a while but right when i start up...which leads me to believe its not the ignition control module...Ive been told its actually the other way around...it acts up after its been running awhile. any help would b greatly appreciated.
Thanks in advance
I have a 1981 f100 with the 4.9 300 IL 6, i just timed it and got it running nice. On Friday night i was stuck at a RR crossing so i shut off my truck waited till the train moved, after it did, I proceded and my truck was acting like it didn't want to accelerate. Well after getting up to speed of about 35MPH the 'stuttering' went away. On saturday i got up and made it out the door and the stuttering resumed. i talked to the shop foreman at work, and he suggested it was my ignition control module, said that its possible for it to go bad because the gel inside will melt which it has, so i replaced it with one around the shop (believe it or not). Still doing the same thing, i cleaned out my fuel filter, looked under the distributer cap for condensation, found nothing and still it continues...not after ive been running a while but right when i start up...which leads me to believe its not the ignition control module...Ive been told its actually the other way around...it acts up after its been running awhile. any help would b greatly appreciated.Thanks in advance
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From: S. Mississippi
Just as a long shot, it could be the coil thats causing your problem. Though it wouldn't make sense. The coil would act up when the engine was hot, not when it was cold.
Hows your choke working? That could be part of the issue. Actually other than the coil thats about all i can think of.
Hows your choke working? That could be part of the issue. Actually other than the coil thats about all i can think of.
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Just as a long shot, it could be the coil thats causing your problem. Though it wouldn't make sense. The coil would act up when the engine was hot, not when it was cold.
Hows your choke working? That could be part of the issue. Actually other than the coil thats about all i can think of.
Hows your choke working? That could be part of the issue. Actually other than the coil thats about all i can think of.
About 8 months ago i replaced my carb, and after i connected it and started it i was testing the engine out and when i gave it gas, it died on me, i found that i didnt hook the line up...where exactly does this line go on my intake manifold? any kind of diagram would be great and suggestions on how to repair this.
ps i live in louisian so you know that currently we are seeing temperatures of around 85+ degrees at 9am (which is when im heading to work). so as far as needing to set the choke when i get in, i didnt think was necessary, correct me if i am mistaken, or are you saying cold start as in 'it hasnt ran since the night before, so the engine is cold'
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If the choke is sticking, the engine will bog and you won't have any power to take off will. Sometimes it will show up as the engine shuddering, other times it just feels like you are running on 2 or 3 cylinders.
That metal line should actually connect to your exhaust manifold. It supplies heat from the exhaust to make the choke pull off faster. Be mindful that this metal line will cause a vacuum leak, and will cause the truck to idle higher than normal, and run leaner. If you can, re-connect it.. if not, cap it off to eliminate the vacuum leak. Also take your air cleaner off, and start the truck, and see if the choke "flap" at the top of the carb is opening up as the engine warms.
I hear you about the mid-morning heat, where i'm from we've been setting record temps for the past week...and there is no end in sight. Sucks when you've got an older vehicle that you love working on, and no garage!
That metal line should actually connect to your exhaust manifold. It supplies heat from the exhaust to make the choke pull off faster. Be mindful that this metal line will cause a vacuum leak, and will cause the truck to idle higher than normal, and run leaner. If you can, re-connect it.. if not, cap it off to eliminate the vacuum leak. Also take your air cleaner off, and start the truck, and see if the choke "flap" at the top of the carb is opening up as the engine warms.
I hear you about the mid-morning heat, where i'm from we've been setting record temps for the past week...and there is no end in sight. Sucks when you've got an older vehicle that you love working on, and no garage!
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i thank you very much for your wisdom. i have done just as you suggested, also i seen that the wire goingto the electric choke was all messes up, so i spliced in some new wire and also opened the choke all the way for a temporary fix until i can get the kit to repair the metal line. it runs 110% better. I bet the line finally broke as i was idling at the RR crossing. well anyway thank you once again for your wisdom.
