1980 - 1986 Bullnose F100, F150 & Larger F-Series Trucks Discuss the Early Eighties Bullnose Ford Truck

302 starting problem

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Old 09-30-2012, 09:22 PM
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302 starting problem

Hey guys,
I have an 85 f150 with the efi 302 and sometimes when the motor is cold it'll crank right up. But every other time I want to start it, I have to keep the pedal floored. I have a feeling that it's definitely a mechanical issue.
Any help will be appreciated.

Thanks,
Mario
 
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Old 09-30-2012, 09:58 PM
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If it's EFI, it's controlled by a computer, so ask the computer what it thinks is happening:

Fuel Injection Technical Library » How To Run a Self-Test
 
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Old 09-30-2012, 10:07 PM
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I pulled codes. It said I had a problem with the MAF sensor. But I don't have a MAF sensor. Is it maybe pointing to a faulty MAP sensor?
 
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Old 09-30-2012, 10:40 PM
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What was the code number?

And, was it in:

KOEO or
CM or
KOER?

Procedures (and interpretations) are sometimes different depending on which of the three the code shows up in.
 
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Old 09-30-2012, 11:00 PM
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I did koeo and koer. It's code 185 if my book that came with the scanner. It says "MAF sensor- signal voltage is lower than expected"

But I'm confused caused I have a MAP sensor and not a MAF.
 
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Old 09-30-2012, 11:04 PM
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Originally Posted by olfaithful85
I did koeo and koer. It's code 185 if my book that came with the scanner. It says "MAF sensor- signal voltage is lower than expected"

But I'm confused caused I have a MAP sensor and not a MAF.
I can look in my 1986 book and see what it says.

Code 185, according to Old Fuel Injection, comes only in CM. So, I will assume yours is coming from CM but I will have to look in the Ford book to know more for certain.
 
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Old 09-30-2012, 11:07 PM
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Yeah I could be wrong. I'm missing a bunch of pages in my book lol so it could very well be a cm test I could have ran. I'm just not entirely sure cause it was the first time I ever pulled codes.

Thanks for the help
 
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Old 09-30-2012, 11:32 PM
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OK, we have a problem... my 1986 book lists only two-digit codes as a possible output in 1986.

I for some reason don't think they'd flip-flop using 2- or 3-digit codes in the different years.

Add to this, you don't have a MAF sensor, you have a Speed-Density system.

Are you absolutely sure you're using that thing right?

Might read that oldfuelinjection site closely; the Ford powertrain diagnostic manual is VERY clear on stating what error codes need to be dealt with in what specific order. If you have only one code, this isn't a big deal. But I'm highly suspicious of an error 185 in 1985.

Nevertheless, I looked up 185 in my 1993 book (we had 3-digit codes by then).

185 shows up only in CM, the title is:
In-Range MAF/TP/Fuel Injector Pulse Width Test

First step in diagnosis is:
CHECK INTAKE AIR TEMPERATURE (IAT) SENSOR

You don't have an IAT sensor! (I could be wrong there, but I don't think you do, anyhow.)



OK, please go verify your codes. Maybe read the oldfuelinjection.com site and do it manually by counting blinkenlights. Maybe go to a parts store and have somebody read codes for you (can be problematic as some kids in part stores don't know how to read OBD-I codes, it's from before they were born).

But I really don't think 185 is right on a 1985. I will ask Ralph to verify, he has more books than me.
 
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Old 09-30-2012, 11:54 PM
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Well the book I have came with the scanner I got. The brand of the scanner is "actron." And the scanner worked by plugging it in and counting flashes on the scanner. And I can't take it to autozone cause it's not registered cause its a mud truck and I would definitely not have some kid scan it there anyways after my grandpa went there to get his battery changed and the kid didn't know how to change it LOL!

I'm pretty sure I pulled the codes correctly because I did the tests twice.

I think it's a map sensor and it's only like 40$ so I may just go get one and see if that's the problem.

But yes, please get back to me when you find out more of that information from your friend Ralph and please get back to me. I really appreciate it.
 
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Old 10-01-2012, 01:34 PM
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Originally Posted by olfaithful85
But yes, please get back to me when you find out more of that information from your friend Ralph and please get back to me. I really appreciate it.
This will be 81-F-150-Explorer, I asked him to stop by. I don't think we had 3-digit codes in 1985 but I've been wrong before and I'll be wrong again, just watch and see.
 
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Old 10-01-2012, 01:57 PM
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Ok awesome thanks
 
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Old 10-01-2012, 02:11 PM
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I've seen it mentioned here that flooring the accelerator while turning the key to START puts the computer into clear-flooded-engine mode, which would lead me to believe your problem might be one or more leaking injectors? The computer won't know about that, nor do I know how to determine if such a situation might exist.

Maybe others can add more?
 
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Old 10-01-2012, 03:10 PM
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Interesting. I guess I'll have to check on that. Though I really hope I don't have to spend the money on new injectors lol.
 
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Old 10-01-2012, 08:09 PM
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Ok, there is a problem somewhere...

The first year of 3-digit codes is 1991. So the 1985 can not have a 3-digit code system from the factory.

Was the computer system swapped out for a later model?
 
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Old 10-01-2012, 08:20 PM
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Originally Posted by 81-F-150-Explorer
Was the computer system swapped out for a later model?
Now, that might explain some things! You see people here talking about how they think they can just swap a computer *****-nilly........

Maybe a PO did that, couldn't get it to run right (Shocking!) and sold it to you for cheap.... it's happened before....
 


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