trucks not a morning person

Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.

jsomedaysoon

New member
Joined
Jan 12, 2008
Messages
392
Reaction score
1
Location
outer banks nc
I'm working on an 87 with a strait six in it... i just bought it a few weeks ago. it refuses to start until about 10 in the morning. anything later than that it starts and runs fine. i don't even know where to begin diagnosing this. if anyone can give me some direction i would appreciate it.

 

Rons beast

Active member
Joined
Dec 13, 2007
Messages
1,537
Reaction score
13
Location
Florida..in my mind , sitting on the beach
Let's start at the Beginning. When you say it won't start, I'm going to assume that it cranks.

When it won't start check if you are getting spark rto the plugs...If not...it's a spark porblem.

If you are getting spark, are you getting fuel? If not...then it's a fuel problem. Don't know the 6 off the top of my head, but is it carbed? Does the choke close tight?

Let's start there.

A quick guess based on where you live.....could you be getting condensation in the distributer cap?

Run with the checks and let us know more.

Good Luck

 

Krafty

New member
Joined
Feb 17, 2007
Messages
1,063
Reaction score
5
Location
Ontario Canada
being as you just bought i would recommend getting new plugs, wires, cap and rotor to start as well as a fuel filter and air filter.

its always good to start with a fresh tune up.

an 87 with a strait 6 is a feulie so that choke idea goes out the window.

if it does spin but wont fire then I agree with the condensation under the cap idea witch will be fixed with the new cap and rotor.

any more specific details you can give us about your issue will lead to a more specific answer.

good luck,

 
OP
OP
J

jsomedaysoon

New member
Joined
Jan 12, 2008
Messages
392
Reaction score
1
Location
outer banks nc
thanks for the input sorry for the slow reply i've been really buys. so yea the truck does crank and considering that it does run just fine in the afternoon i kinda put fuel and spark to the back of my mind. i was thinking either like ya'll the distributor cap or something like that. i could've sworn i had read something in my haynes about a barometric pressure sensor but now i can't find it. i was thinking maybe the barometric pressure was different in the morning or something... probably a shot in the dark but i agree with ya'll about the usual things that you do when you buy an old truck. the fuel filter looks brand new but i'm about to change the distributor cap and all that good stuff and see what happens.

 

miesk5

96 Bronco 5.0
Staff member
Moderator
Joined
Oct 18, 2005
Messages
9,071
Reaction score
1,018
Location
Floating in the Pacific
yo,

I agree w/moisture on and inside cap (check for a crack(s); plug wires, etc.

Try a self test for codes.

By our buddy here BroncoJoe @ http://broncozone.com/topic/14269-code-reader/page__pid__74587__mode__threaded

do the KOEO = Key On Engine Off portion first

& Remember to have engine @ Normal Operating Temperature before doing the KEY ON ENGINE RUNNING (KOER) portion

Post any Code(s) found here by

KOEO

&

KOER

--

Overview & Testing, Bronco & Ford - "The Barometric Pressure (BP) sensor operates as a piezoelectric (pressure-sensing) disc. However, rather than generating a voltage, its output is a frequency change. The sensor changes frequency relative to intake manifold vacuum. The sensor frequency increases as vacuum increases. The BP sensor is used to sense the changes in barometric pressure, allowing the PCM to sense the altitude at which the vehicle is operating. Its signal affects, spark advance for altitude compensation.

The BP sensor was only used in early MAF systems. Starting in 1994 Ford learned that air pressure can be calculated once the MAF sensor tells the computer the amount of air ingested by the engine.

" Source: by Ryan M (FireGuy50) at fordfuelinjection.com

Loof for the BP on passenger side firewall, high as shown in this 90 diagram by Chilton

and fyi

Engine Bay Diagram in an 87-88 4.9L; #1 Source: by Ford via Chilton

Engine Bay Diagram in 87-88 4.9L; #2 Source: by Ford via Chilton

 
OP
OP
J

jsomedaysoon

New member
Joined
Jan 12, 2008
Messages
392
Reaction score
1
Location
outer banks nc
so i was talking to my step dad and he told me that its not actually cranking in the morning. basically he can't get ANY sign of life out of it. not a click or anything. so that changes things a little bit. it's baffling because in the afternoon it starts as soon as you hit the key the first time with no trouble at all.

 

miesk5

96 Bronco 5.0
Staff member
Moderator
Joined
Oct 18, 2005
Messages
9,071
Reaction score
1,018
Location
Floating in the Pacific
yo,

ok,

C\No click @ starter relay

Do headlights come on and look ok (hard to see in morning sun unless you park it against a dark colored wall or hold cardbd up in front of em; and does horn honk?

I'd start w/basics @ batty; pull cables from each post and clean posta and inside terminals; look for corrosion on wire strands leading back to inside on terminals. Check ground cables to engine, frame, firewall (if equipped), etc.

Have a meter?

check for continuity and voltages during at rest with nothing on.

then w/head lights and all other stuff on and then key to start

 

Members online

No members online now.

Latest posts

Forum statistics

Threads
22,509
Messages
135,880
Members
25,108
Latest member
Utahstroke
Top