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Discussion Starter · #1 ·
So I fixed my spark plug fouling issue by installing new valve seals. Plugs are dry!! But now the truck started something new. It only starts on second try. First try it starts then looses idle and dies if I don’t give it gas. Then today I was parked nose up and it would start even on the second try. I drift back level and it finally started. I tested the fuel pressure at the rail and it was 30 psi with key on not running. Turned the key again and pressure went to 40. Turned key off and it maintained pressure. Does this sound like my pump is going bad or something else? Truck runs great otherwise. Well….except for the passenger side valave cover gasket that started leaking too. Oil all down the right side under carriage. Always something with these trucks! Thanks.
 

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Everyone is going to ask if you've pulled any codes? I'll assume that hasn't been done, but should be to make this easier.

Does the pump only prime for 3 seconds? Or does it just keep priming? Cause that's a sign of a bad ECM. But if that's not the case then perhaps spark is the issue. I'd check the ignition control module (ICM) I believe it is fender mounted on a 95'. After that I'd consider replacing the Idle Air Control (IAC), then followed by the EGR and EGR solenoid.
 
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Discussion Starter · #3 ·
Hi Siggy,

I pulled codes and I get 334. So that's EGR right? The pump primes for about 3 seconds then shuts off. The ICM and AIC are both new. I'm thinking it could be the fuel pressure regulator?
 

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Yo Troy,
DTC 334 EGR (EVP) in either KOEO = Key On Engine Off, or CM = Continues Memory, or KOER = Key On Engine Running indicates a closed valve voltage higher than expected; "...Failed sensor, & as rla2005 (Randy) wrote; carbon between EGR pintle valve and seat holding the valve off its seat. Remove the EGR valve and clean it with carbon remover. Prior to re-installing see if you can blow air through the flange side of the EGR by mouth. the egr is not closing properly which can cause detonation. remove the egr and clean off any carbon built up on it with carb cleaner and a brush if necessary. The EGR Valve Position (EVP) Sensor used exclusively by Ford, can be the cause of driveability problems without ever setting any trouble codes. The relationship between the EVP sensor and the EGR valve is important to understand. Either one being out of spec can cause similar symptoms. Understanding this relationship will help you to diagnose uncoded driveability problems like stumbles, hesitations, rough idles and stalling..."
Source: by rla2005 (Randy) at FSB
View attachment 177969

View attachment 177970
Testing; "...There shouldn't be any vacuum at the EGR valve at idle or any time your ass is under the hood fiddling with it, to put it plainly, except for perhaps a very light residual vacuum from the EVR. Check ALL of your vacuum lines FIRST, and the vacuum reservoir for leaks..."
Source: by SigEpBlue (Steve) at FSB
 

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Hi Siggy,

I pulled codes and I get 334. So that's EGR right? The pump primes for about 3 seconds then shuts off. The ICM and AIC are both new. I'm thinking it could be the fuel pressure regulator?
yes 334 is for the EGR, BUT could also be an indicator of a vacuum issue somewhere that is just manifesting in the EGR valve malfunction. I'd replace the EGR valve ($100 I think), and replace all of your vacuum lines with rubber or silicon if not already done to eliminate any potential vacuum issues.
 

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Yo
As Siggy89 advised ●See my Vacuum leak test in post #11 includes jowens1126 HVAC Control Panel info @ Help with dtc codes and idle
 

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Discussion Starter · #7 ·
So I replaced the fuel pressure regulator and drove it for about ten minutes. The temperature gauge climbed to the “L” and then swung back down. I pulled in the garage and when I tried to start it back it it cranked but does not start. I guess My next try is a new EGR. I can’t find ang vacuum leaks. So frustrating!
 

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So I replaced the fuel pressure regulator and drove it for about ten minutes. The temperature gauge climbed to the “L” and then swung back down. I pulled in the garage and when I tried to start it back it it cranked but does not start. I guess My next try is a new EGR. I can’t find ang vacuum leaks. So frustrating!
so you’ve replaced all the original vac lines?
 
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Discussion Starter · #9 ·
not yet. They are in decent shape. The current situation seems like I don’t have any spark. I cranked and grounded plug but not seeing any spark. Last time I replaced the icm and that fixed it. I have new plugs, wires, rotor and cap. Coil is good. Just lost now!
 

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I'd replace all those lines. They may look to be in decent shape, but there are almost certainly cracks in the old plastic lines. Improving the vacuum system will produce noticeable improvements and allow you to know "for sure" that the vacuum is not the issue.

You can always get a new Throttle Position Indicator (TPS) just to eliminate one more thing. Have you looked at the EGR tube under the intake manifold? Sometimes those brake.

Is it possible the leaking valve cover on the passenger side is fouling the plugs? What's your firing order? It should be 1-3-7-2-6-5-4-8 for a 5.8 I believe. Are the plug wires crossing over each other? Might produce some electrical issues.
 
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Discussion Starter · #11 ·
I'd replace all those lines. They may look to be in decent shape, but there are almost certainly cracks in the old plastic lines. Improving the vacuum system will produce noticeable improvements and allow you to know "for sure" that the vacuum is not the issue.

You can always get a new Throttle Position Indicator (TPS) just to eliminate one more thing. Have you looked at the EGR tube under the intake manifold? Sometimes those brake.

Is it possible the leaking valve cover on the passenger side is fouling the plugs? What's your firing order? It should be 1-3-7-2-6-5-4-8 for a 5.8 I believe. Are the plug wires crossing over each other? Might produce some electrical issues.
Hi Siggy! I pulled the plugs on the passenger side and they looked clean. I'll start working on the vacuum lines. I'm just afraid I'm plug something in wrong. I'll also check the wires are crossing. I have a ICM arriving tomorrow. I'm hoping that will work but seems odd that keeps going bad. I also will replace the EGR since that was throwing a code 334. HAte having my truck sitting dead =(
 

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Yo Troy,
When vacuum leaks are indicated, search out and correct the condition. Excess air leaking into the system will upset the fuel mixture and cause conditions such as rough idle, missing on acceleration, or burned valves. If the leak exists in an accessory unit, such as the power brake, the unit will not function correctly. Or Air Conditioni
 

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So i unplugged my spout and the truck starts!
That usually indicates you have a bad computer. With the SPOUT plug removed the ICM will trigger off the raw PIP signal from the distributor. Plugged in the computer controls the spark.
 
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Discussion Starter · #15 ·
That usually indicates you have a bad computer. With the SPOUT plug removed the ICM will trigger off the raw PIP signal from the distributor. Plugged in the computer controls the spark.
Where would be the best place to get a new one? Rock auto seems to be the least expensive.
 

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No one has new ones, they are all remanufactured. That is a loose term the "rebuilders" use. The issue could be as simple as leaking capacitors in the computer. Very common issue that can be repaired. Pull yours out then open it up for inspection. There are a few places that repair these boxes. I think Miesk5 has a few links to true repair vendors.
 

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Discussion Starter · #17 ·
I pulled my computer. The number reads. FSTF-12A650-BXA. There is a larger font number: ROB0

seems like the “bxa” are harder to find. Any idea what the numbers mean?
 

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Discussion Starter · #18 ·
So I swapped out the computer and the truck still will not start unless I pull the spout. When I pull the spout it starts right up and idles great. What am I missing? Need help please!
 

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Discussion Starter · #20 ·
Well i wiggled some of the wires coming out of the distributor and to my surprise the truck started! It’s been running every since. Now my concern is that it’s not reliable. Thinking I should just replace the distributor. I hate electrical stuff!
 
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