efi 300 6 wont run when hot out
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efi 300 6 wont run when hot out
Hi everybody, im new here. I was wondering if i could get some input on something. Im the proud owner of a 1987 Ford F150 Custom 300 L6 4 speed 2wd. She doesnt like being run during the day and when its hot. Ive managed to drive to chicago from peoria il during the evening yet she wont drive 20 minutes during the day. It wouldnt even start yesterday when it was 93° out. Ive replaced the plugs and wires and a high pressure fuel pump. I wanted some input because i dont have money to fire off the parts cannon nor the equipment or time to diagnose because i work 3rds. Thanks guys, any input would be appriciated.
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Hey there chumbucket1987. From what I understand, extreme heat results in thermal expansion. SO something is getting too hot, and shorting out. Does it just turn over and over, without starting? Maybe it is your coil (if EFI has those), try giving it a feel to see if it gets hot.
FTE Legend
Joined: Nov 2015
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From: Angier, NC
Chum, Welcome to FTE.
You may want to post this question over in the 80-86 (I know you have a 87) area https://www.ford-trucks.com/forums/forum37/
As there are more guys over there that can help you on this.
Just my thinking as I am not up much on the computer trucks but being EFI you have a computer, with a computer it should be able to "tell you" thru codes what is going on.
If you don't know how to, I don't as I don't have a computer controlled truck so don't read much on it. Any how the link they should be able to help you do so.
I am sure you will need some tools, like a test light, a fuel pressure test gauge, both are cheap.
With out more info like when it dies driving it is hard to say what it could be but can only be 2 things.
For a guess fuel or spark and a little deeper more to spark but with out testing cant say for sure.
From what I have seen posted in the 80-86 area that truck may use the TFI IGN system, small box bolted into the dist. They like the older boxes on the fender well fail when old and with heat.
Dave ----
You may want to post this question over in the 80-86 (I know you have a 87) area https://www.ford-trucks.com/forums/forum37/
As there are more guys over there that can help you on this.
Just my thinking as I am not up much on the computer trucks but being EFI you have a computer, with a computer it should be able to "tell you" thru codes what is going on.
If you don't know how to, I don't as I don't have a computer controlled truck so don't read much on it. Any how the link they should be able to help you do so.
I am sure you will need some tools, like a test light, a fuel pressure test gauge, both are cheap.
With out more info like when it dies driving it is hard to say what it could be but can only be 2 things.
For a guess fuel or spark and a little deeper more to spark but with out testing cant say for sure.
From what I have seen posted in the 80-86 area that truck may use the TFI IGN system, small box bolted into the dist. They like the older boxes on the fender well fail when old and with heat.
Dave ----
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Joined: Sep 2012
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This could be a symptom of the ignition control module going bad. It's located on the distributor. The ICM was relocated to the driver's side fender and placed on a heatsink in later years.
Try to pull codes. Your continuous memory (CM) codes will hopefully tell the story. You get the CM codes when pulling key-on-engine-off (KOEO) codes. You can use a paperclip and count check-engine light flashes to get the codes. A better option is to get a code reader. Innova makes one and it's like $25 on Amazon and $30 at a parts store. The parts store might be able to pull codes for you, but all the ones around me only do OBD-II and up.
Try to pull codes. Your continuous memory (CM) codes will hopefully tell the story. You get the CM codes when pulling key-on-engine-off (KOEO) codes. You can use a paperclip and count check-engine light flashes to get the codes. A better option is to get a code reader. Innova makes one and it's like $25 on Amazon and $30 at a parts store. The parts store might be able to pull codes for you, but all the ones around me only do OBD-II and up.
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Update, have replaced coil and spark control module. Its a fuel system issue as discovered by using starting fluid. Currently replacing new fuel pump and fuel filter. Any of you guys have issues with oreillys fuel pumps?
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Update: Replaced fuel pump and fuel filter. Figured out its a woring issue. Ill cross post this like said above. If any of you can think of a way for me to install a bypass that includes the relay, that would be very helpful. Thanks folks!
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FTE Legend
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From: Angier, NC
Ok from what I have seen posted electric fuel pumps have some safety devices to keep the pumps from running when they are not.
There is something about an oil psi switch that if no oil psi , motor not running, the switch opens and no power to pump.
The other is an inertia switch, when truck is hit/crashed and some times bumped, it opens.
I hear this switch is behind the glove box area.
I think both can be jumped out for testing only.
Dave - - - -
There is something about an oil psi switch that if no oil psi , motor not running, the switch opens and no power to pump.
The other is an inertia switch, when truck is hit/crashed and some times bumped, it opens.
I hear this switch is behind the glove box area.
I think both can be jumped out for testing only.
Dave - - - -
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