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jerky - Stuttering when driving

Well hopefully I can explain this clearly. About 3 months ago I was driving to pickup my brother from school and the bronco died on me in the intersection and would not start. Towed it back to the house and replaced all the spark plug wires, spark plugs, cap and rotor, fuel filter, fuel pump, and finally the stator which got it running. We timed it and took it for a test drive. It had no get up and go at all compared to before the problems. And at about 35-40 mph it will start jerking back and forth and it shakes a bit unless you let off the gas or speed up. Took it to the mechanic as we could not figure it out and they said it had low compression in 4 of the cylinders or something like that. Drove it to have lunch with my mom today and it still ran like crap. Drove it back to the house and it had the power back but the jerkyness was still there but not nearly as bad. Any ideas on what it could be would be great.
 

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Roller rockers are gay
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Did you unplug the SPOUT connector before timing it? If not then it isn't timed properly.

That's also a LOT of cash wasted on throwing parts at it, and work. Holy Jesus it's no fun dropping a fuel tank.
 

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Discussion Starter #3
Did you unplug the SPOUT connector before timing it? If not then it isn't timed properly.

That's also a LOT of cash wasted on throwing parts at it, and work. Holy Jesus it's no fun dropping a fuel tank.
We followed the instructions on the hood and we did unplug something but I don't remember what it was.
And yea, Dropping the tank sure did suck. Took us the whole day and not having all the parts for it sure did make it easy for us. And the reason for it was I think the guy at autozone said to check the fuel railing pressure I think it was and it it ended up being low.

EDIT: Looking at a picture of the instructions and yes we did unplug the SPOUT
 

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Start at the basics. Fuel, air, spark. Compression doesn't just "disappear" unless you have catastrophic damage. You'd know if that happened. Double check your timing, make sure the wires aren't crossed, check your fuel pressure with a gauge, not a screwdriver in the schraeder valve. You need about 35-40psi for the truck to run right.
 

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Discussion Starter #5
Start at the basics. Fuel, air, spark. Compression doesn't just "disappear" unless you have catastrophic damage. You'd know if that happened. Double check your timing, make sure the wires aren't crossed, check your fuel pressure with a gauge, not a screwdriver in the schraeder valve. You need about 35-40psi for the truck to run right.

We did fuel and spark, That was the reason for checking the fuel rail and we did use a fuel pressure with a guage.I think it was at 35 and the guy said it should be at 70 if i remember correctly. When we took it to the mechanic we apparently had the timing off a bit so they fixed that, all though wouldn't hurt to double check that. And my dad did notice the air intake valve wasn't opening a whole lot when we were reving the engine if that could be related. And lastly, What do you mean by crossed wires?
 

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My first reaction would have been fuel system related. Sounds like you've eliminated that with replacing parts and pressure check. Next, double check the plug wires are all in the correct position.

Long shot, is there any chance the exhaust is plugged up?
 

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My first reaction would have been fuel system related. Sounds like you've eliminated that with replacing parts and pressure check. Next, double check the plug wires are all in the correct position.

Long shot, is there any chance the exhaust is plugged up?
It's an original muffler and I think both ends have been rusted through the weld. When I accelerate, There is alot of weird sounds coming from it. Gona have to replace that soon.
 

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Autozone boy was wrong of lying. You replaced a fuel pump for no reason.
 

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Just got mine back from shop for the same thing! I only had 5 cylinders firing!!! Check injectors! A rat chewed three of the injector wires in two, which caused them to stop firing.
We also got the spark pugs,wires and rotor cap replaced just for good measure
 

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Oh yes and a bad vacuum line somewhere in the mix! It fixed the problem. Fuel line is sacking air now... It never ends....
 

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The fittings connecting my fuel filter to the line arnt staying on slipping from line which kills power because no seal equals sucking air! Mine will barely run because of it you might check that out as well! I'm going to work on fixing mine this coming week hopefully I get it going!
 

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Did you happen to "pull codes" from the computer to see what elec./electronic "faults" were indicated......? might help narrow things down, no?


Good Luck ~ :thumbup
 

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Did you happen to "pull codes" from the computer to see what elec./electronic "faults" were indicated......? might help narrow things down, no?


Good Luck ~ :thumbup
We don't own the reader needed nor does anyone we know have one. So we weren't able to pull codes but the engine light has been off since we placed the stator I believe.
 

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All you need to pull codes for pre 1996 is a paper clip and the ability to count.
 

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yo Blaze,
As JK and TheUnforgiven advised;

Try a Self Test for Diagnostic Trouble Codes (DTC)s by my pal, BroncoJoe19
http://broncozone.com/topic/14269-co...&mode=threaded
A helper is good to assist in reading Codes; best is to take a cell fone vid and replay it.
Some basics;
Visual Check
Battery is fully charged
1.Inspect the air cleaner and inlet ducting.
2.Check all engine vacuum hoses for damage, leaks, cracks, blockage, proper routing, etc.
3.Check EEC system wiring harness for proper connections, bent or broken pins, corrosion, loose wires, proper routing, etc.
4.Check the Powertrain Control Module (PCM), sensors and actuators for physical damage; can use these two diagrams to locate ACT, TPS, EVP above EGR), Ignition Control Module (ICM) on distributor mounted years (Ford re-located the ICM from Distr side to driver side hood hinge area on inner fender liner in 92-96); to MAPand Sensor Locations Diagram ECT, IAT and Water Temperature Gauge Sender; Sensor Locations Diagram ECT & Temp Gauge sender, PCV by Gacknar

5.Check the engine coolant for proper level and mixture.
6.Check the transmission fluid level and quality.
7.Make all necessary repairs before continuing
8. Check headlights

The engine temperature must be greater than 50° F for the Key On Engine Off (KOEO) Self-Test and greater than 180° F for the Key On Engine Running (KOER) Self-Test.
Run it around to heat the engine up and shift thru all gears including Reverse.

Make sure A/C is off and transmission is in Park (automatic); or in Neutral for a Manual & release clutch.

Turn off all accessories; radio, lights, A/C, heater, blower, fans, etc. (close driver's door)

Then turn off engine and wait 10 seconds.

Do KOEO test First

Post Code(s) here according to:
KOEO
&
KOER



Fuel Pressure in KOEO Should be 35—45 PSI but gauge may need calibration, if possible and/or ambient & Under hood temperatures affects accuracy;

KOER Should be 28—45 PSI

w/ Fuel Pressure Regulator Vacuum line unplugged - 35PSI
Maximum fuel pressure is obtainable at WOT or the vacuum hose removed from the fuel pressure regulator.
Should be at high end of 35-45 PSI
If fuel lines/systems have been drained or evacuated, it may take up to 15 seconds to obtain the pressure specified.
 

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The last time I checked you could buy one on Amazon for $24.99 with the diagnostic book.......worth every penny IMO.......or look around the house for an old pc.....lol lol


Good Luck ~ :thumbup
 

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Well hopefully I can explain this clearly. About 3 months ago I was driving to pickup my brother from school and the bronco died on me in the intersection and would not start. Towed it back to the house and replaced all the spark plug wires, spark plugs, cap and rotor, fuel filter, fuel pump, and finally the stator which got it running. We timed it and took it for a test drive. It had no get up and go at all compared to before the problems. And at about 35-40 mph it will start jerking back and forth and it shakes a bit unless you let off the gas or speed up. Took it to the mechanic as we could not figure it out and they said it had low compression in 4 of the cylinders or something like that. Drove it to have lunch with my mom today and it still ran like crap. Drove it back to the house and it had the power back but the jerkyness was still there but not nearly as bad. Any ideas on what it could be would be great.
Replace the Ignition Control Module. Had same problem in 3 different ford EFI trucks and that fixed them
 
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