Bronco Forum - Full Size Ford Bronco Forum banner
1 - 15 of 15 Posts

·
Registered
1993 XLT; 5.0; A/T
Joined
·
82 Posts
Discussion Starter · #1 ·
Alrighty folks,

now that we’ve remedied the battery draw, I am faced with another start issue!
My assumption is the fuel line, possibly fuel pump or filter? I need some advice.

When she first starts, I have to crank it twice. First time sputters, second time I tap on the gas and she sputters then catches her breath.. so to speak. Sometimes she’ll catch on the first crank after sitting for a while, but it’s a slow start. But she always fires right up if she’s only been sitting for a few minutes.
It’s obviously something in the fuel line, correct?
my thought was to replace the fuel filter this weekend (I’ve read up on the technical write ups here), and put some sea foam in the tank.. and hope that’s the easy answer.
Is there something else I should look at while I’m down there? Does this sound like I’m going in the right direction, or way out in left field?

182714
 

·
Registered
Joined
·
227 Posts
hi @Rexx -
if you're thinking that your filter is causing a restriction that makes the engine sputter at initial start, what makes it not be a restriction on the second try?

i would want to know what the current fuel line pressure is to determine if fuel supply is really the issue.

the other thing that's happening when you tap the gas is that you're improving air supply by opening up the throttle plate so there's a variable that needs to be eliminated.

that said - i don't think any harm of course from swapping in a good filter
 
  • Like
Reactions: Rexx

·
Ford Hoarder
78 & 92
Joined
·
7,714 Posts
Also someone has changed the lines there. It should have braided lines, with the sometimes hard to release quick connectors.
The filter I agree likely will not fix your issue. It sounds like it may loose prime or something like that. This could be a bad fuel pump, but it is easy to check the fuel pressure regulator as well
ON these trucks the fuel system runs a loop up to the engine and back to the tank. When you key on you sould hear the pump turn on for a few seconds, this should prime the system. If the filter was the only issue, I would expect you would have engine running issues all the time, not just at start up.

I would look over everything well and make sure everything looks fine, since someone has modified the fuel lines at the filter connections already. These should also be high pressure rater connections, while it doesn't look like the worm style clams and rubber hose has leaked, it is not really 100% right. (though it maybe working just fine)
 

·
Registered
1993 XLT; 5.0; A/T
Joined
·
82 Posts
Discussion Starter · #4 ·
hi @Rexx -
if you're thinking that your filter is causing a restriction that makes the engine sputter at initial start, what makes it not be a restriction on the second try?

i would want to know what the current fuel line pressure is to determine if fuel supply is really the issue.

the other thing that's happening when you tap the gas is that you're improving air supply by opening up the throttle plate so there's a variable that needs to be eliminated.

that said - i don't think any harm of course from swapping in a good filter
I don’t really know, my thought was that it was likely an issue with the fuel line- first crank there’s no fuel pressure built up, second it starts to build and catches- the filter is something I’m confident I can do by myself and it looks old as heck so maybe it wasn’t functioning properly.
I didn’t even think about the air flow facepalm

so step one is to determine fuel pressure to see if that’s actually the issue. Makes sense.
If it’s not, I should be looking at air intake?

one of the write ups I read here said it’s a good idea to change the filter every 3k miles, which sounds a bit excessive to me, but what do I know.
 

·
Super Moderator
Joined
·
28,819 Posts
Yo Rexx,
Let's eliminate slow cranking first if it's an issue.
Voltage; "...a normal battery that is fully charged produces 12.6 volts, not just 12.0 V. (Remember, when measuring battery voltage, everything in the car should be off, or the battery should be disconnected. Voltage measurements are always "no load" measurements unless the battery is being tested for it's performance under load)..." by Gordon

  • Starter Motor Cranks Slowly
  • Loose or corroded battery cable connections.
  • Undercharged battery.
  • Loose or corroded starter motor connections.
  • Malfunctioning starter motor.
Pinpoint Tests
NOTE: Use Rotunda Digital Volt-Ohmmeter 014-00407 or equivalent to perform electrical pinpoint tests.

PINPOINT TEST A: STARTER MOTOR CRANKS ENGINE SLOWLY OR NO CRANKING WITH RELAY/SOLENOID CLICKING OR CHATTERING
A1 CHECK CONNECTIONS AT BATTERIES

  • Inspect all battery cable connections for looseness and corrosion.
Are battery connections clean and tight?
YesNo
GO to A2.CLEAN and TIGHTEN connections at batteries.
A2 STARTER LOAD TEST
  • Perform starter load test. Refer to Component Tests in the Diagnosis and Testing portion of this section.
Did starter pass load test?
YesNo
GO to A3.TEST batteries. REFER to Section 14-00. If batteries are OK, GO to A4.
A3 CHECK FOR EXCESSIVE RESISTANCE
  • Perform voltage drop tests. Refer to Component Tests in the Diagnosis and Testing portion of this section.
Did starter circuit pass voltage drop test?
YesNo
GO to A4.CLEAN circuit connection as necessary.
A4 STARTER NO-LOAD TEST
  • Perform starter no-load test. Refer to Component Tests in the Diagnosis and Testing portion of this section.
Did starter pass no-load test?
YesNo
Slow cranking is caused by excessive engine drag.REPAIR or REPLACE starter.
." by Ford in 96 Bronco/ F Series Workshop Manual partial @ 1996 Bronco/F-Series

Check both battery posts, cables, connectors & major GROUND cables for looseness and corrosion. If you see corrosion on a cables' wires strands between connectors or lugs and leading into the insulation, peel back the insulation to see how far back it reaches.
by El Kabong @
"Cheesy clamp on end. Do not use for a long term repair. Only to get you home when nothing else is available. If you have one of these, suspect it before anything else" El Kabong @ Common Replies to FAQs

Check starter relay for looseness or rust to the inner fender. It's ground is through its body to the inner fender.
Check that starter is mounted securely and connectors are clean and tight

CHECK GROUND CABLES to frame, block etc.
Slow Cranking or a Grinding Noise; "... Problems with the negative battery cable is a major cause of starting problems in Ford, Lincoln, and Mercury vehicles. Bad battery cables can cause slow cranking or a grinding noise when trying to start an engine. ..,the wire connection inside the battery terminal connector corrodes easily. This will cause a voltage drop in the cable and result in low voltage being supplied to the starter. You can check for voltage drop in the cable using a digital voltmeter. Connect the negative probe of the voltmeter to the negative battery post (not the battery terminal connector). Then connect the positive probe to the starter case and crank the engine. The voltage reading should be less than .5 volts. A higher reading means there is resistance in the cable or the battery terminal connector. Clean the cable end and the battery terminal connector and test again. If the voltage reading is still higher than .5 volts, replace the cable and the battery terminal connector..."
Source: by genco1.com

Ground Location, Frame from Battery pic in a 94 5.8;

"...Frame ground just inboard of the R spring tower. The black battery wire goes from the front bolt of the engine mount (on the block) to this tab & up to the battery post, where a smaller black wire goes to the core support, providing a continuous ground path between the engine, frame, battery, & body..."
Source: by CodysBigBlueBronco (how much $???)

Frame Ground location (Passenger side Cross member above
engine mount)

by jowens1126

Intake Manifold to Block Strap on oassenger side Location pic in a 96 5. by bossind



Inspect STARTER RELAY GROUND; relay located on PASSENGER FENDER LINER, near battery, see Starter Relay pic in a 95

Source: by Shane C. (BigBlue, bigbluebronk)

"Long crank times may be traced to a sticking Idle Air Control (IAC) valve"
View attachment 181763


If cranking is OK, as advised, see How To Test The Fuel Pump (Ford 4.9L, 5.0L, 5.8L) @ Part 1 -How to Test the Fuel Pump (Ford 4.9L, 5.0L, 5.8L)
KOEO 35-45 PSI
KOER 38-45PSI

Note: Maximum fuel pressure is obtainable at WOT or the vacuum hose removed from the fuel pressure regulator.

As advised, pull the vacuum line from FPR, if any gas or aroma thereof, replace FPR.


If fuel lines/systems have been drained or evacuated, it may take up to 15 seconds to obtain the pressure specified.

Grounding the FP lead at the DLC will allow the pump to run continuously with the ignition switch on.
182725



If pump passes, Try a Self Test for Diagnostic Trouble Codes (DTC)s by my pal, BroncoJoe19 @ Code Reader


 

·
Registered
1993 XLT; 5.0; A/T
Joined
·
82 Posts
Discussion Starter · #6 · (Edited)
On my way to work this morning she jumped up RPM's in short bursts while I was at a stoplight. Maybe two or three times. One time was enough to jolt me forward about an inch or so.
I pulled over and she revved up again only once while I was at a full-stop. Then for the rest of the ride she was fine. It happened last night once when I was running to the store right down the road, outside of that this is a new thing.

Could this be related? The idle air control valve, right?
 

·
Registered
1993 XLT; 5.0; A/T
Joined
·
82 Posts
Discussion Starter · #7 ·
Also someone has changed the lines there. It should have braided lines, with the sometimes hard to release quick connectors.
The filter I agree likely will not fix your issue. It sounds like it may loose prime or something like that. This could be a bad fuel pump, but it is easy to check the fuel pressure regulator as well
ON these trucks the fuel system runs a loop up to the engine and back to the tank. When you key on you sould hear the pump turn on for a few seconds, this should prime the system. If the filter was the only issue, I would expect you would have engine running issues all the time, not just at start up.

I would look over everything well and make sure everything looks fine, since someone has modified the fuel lines at the filter connections already. These should also be high pressure rater connections, while it doesn't look like the worm style clams and rubber hose has leaked, it is not really 100% right. (though it maybe working just fine)
I noticed all of the write ups had a braided line, and was not surprised to see hose clamps when I crawled underneath to check it all out. I'm finding most things on this truck are very "home-brew".

I'm not sure I hear the pump, but I'm not sure if I know what I'm listening for.

Thank you!
 

·
Registered
1993 XLT; 5.0; A/T
Joined
·
82 Posts
Discussion Starter · #8 ·
Yo Rexx,
Let's eliminate slow cranking first if it's an issue.
Heard. I did just throw a new battery in, but the connections need to be replaced.
I will take a look at all the grounds once I get home, and go on from there!
 

·
Charlie don't surf..
'92 Ford Bronco XLT
Joined
·
16,089 Posts
On my way to work this morning she jumped up RPM's in short bursts while I was at a stoplight. Maybe two or three times. One time was enough to jolt me forward about an inch or so.
I pulled over and she revved up again only once while I was at a full-stop. Then for the rest of the ride she was fine. It happened last night once when I was running to the store right down the road, outside of that this is a new thing.

Could this be related?
hard to say, as advised above, you should start by checking your fuel pressure. That will at least give us a base line.
 
  • Like
Reactions: Rexx

·
Charlie don't surf..
'92 Ford Bronco XLT
Joined
·
16,089 Posts
You'll hear the pump for sure. It will be a 1 to 2 second whine when the key is turned to prime, then once started you'll be able to hear the pump if you go back near the tank.
 
  • Like
Reactions: Rexx

·
Registered
1993 XLT; 5.0; A/T
Joined
·
82 Posts
Discussion Starter · #11 ·
hard to say, as advised above, you should start by checking your fuel pressure. That will at least give us a base line.
That's the general consensus, even one of the articles that Miesk5 linked always comes back to checking the fuel pressure.
Might go pick up a gauge on my lunch break, but then it's going to be even more difficult to return to work when I really just want to play with the truck. Might have to wait for the trip home.
Too bad I can't get paid to learn how my Bronco works... outside of already spending most of my time doing research and perusing this forum.
 

·
Registered
1993 XLT; 5.0; A/T
Joined
·
82 Posts
Discussion Starter · #12 ·
You'll hear the pump for sure. It will be a 1 to 2 second whine when the key is turned to prime, then once started you'll be able to hear the pump if you go back near the tank.
I'll be sure to pay attention when I start it back up this afternoon.
 

·
Registered
1993 XLT; 5.0; A/T
Joined
·
82 Posts
Discussion Starter · #13 ·
Update:

Heard the fuel pump. It was obvious once I paid attention.
The O'reilly I went to didn't have a fuel pressure gauge (they're really letting me down lately), so I just grabbed some air intake cleaner to clean the IAC. It was a huge PITA getting the bottom screw out of it! Cleaned it up, everything that came out of it was black. It looked old as heck though so I will likely pick up a new one while I am at autozone today getting the gauge.
Replaced batt connections, later today when I am on my own computer I will upload a comparison photo. The old connections were absolute trash.

This morning she fired right up, no issue. First stop, idled around 700/800rpm, second stop she dipped down to 300, shot up to 1500, dipped down to 300, shot back up, then it was time to go. Third stop she did the same thing only once, and then for the rest of the drive she idled perfectly at about 700/800rpm. Maybe she just isn't a morning person ;p

Today I will hopefully get the gauge, check the fuel pressure, and all of the grounds.

This weekend I aim to get the fuel filter done, even if it doesn't need to be replaced for this issue, it's probably long over due.
 

·
Super Moderator
Joined
·
28,819 Posts
Yo Rexx,
Rolling Idle perpetrators
182763

Iggie Scope for now
Quick Test is Self Test for Diagnostic Trouble Codes (DTC)s by my pal, BroncoJoe19 @ Code Reader
Vacuum Leaks; see my Vacuum leak test in post #11 @ Help with dtc codes and idle
 
  • Like
Reactions: Rexx

·
Registered
1993 XLT; 5.0; A/T
Joined
·
82 Posts
Discussion Starter · #15 ·
Wee update: got sent home from work due to close proximity with someone with covid (Isolation until my results come in).. been stuck at home without a damned fuel gauge, so I ordered one online. It will get here just in time for the Siren to go to the shop to get the oil pan gasket replaced eyeroll.

So I’ve been working with what I got without being able to go to the parts store!
I replaced the IAC, tightened all of the grounds, and checked my vacuum hoses (to the best of my ability, will have the mech double check my work). Still has the same idle issue at the first two/three stops. It did, however, fire right up this morning after sitting for two days.

Tore out the rest of the wiring for that stupid subwoofer.. along with the subwoofer Itself.. which lead me to remove the interior side panels. The insulation needs replaced, and the panels themselves could probably be soaked in cleaner for a few days and still not be clean. I’m currently waiting for the rusty bolts holding the rear bench seat to soak up some PB so I can knock them loose. The carpet inside is gnarly, and also needs to be removed.

so basically I’ve just been deep cleaning while stuck at home. Got the dipstick in the mail, only to still not find where it is supposed to go. I even checked on the passengers side of the block. Ran my hands all over the dang thing. A few choice words have been muttered about the guy who rebuilt this engine, but it may just be I’m missing it.
 
1 - 15 of 15 Posts
Top