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Slow to fire at startup and now a CEL with no codes

This issue started late last summer where it will turn over longer than normal at startup but always fires and runs fine. Sometimes it's like the starter continues turning even after firing but now more like it just takes longer to fire. I am also getting a CEL within a few seconds of starting, but there are no codes. If I clear the CEL and let it idle it does not come back until I shut it off and restart. I can't drive it due to conditions, but it seems to be running just fine. Any ideas??
 
ArizonaBOSS said:
Fuel Filter / Starter Solenoid / Fuel Pump Relay??? All pretty random for a newer car but worth investigating.

Or bad ground somewhere that's tapping out on something.
Good suggestions. We're starting on the battery relocation tonight but will check those items. I'm hoping it's something with the starter just not that familiar with how they behave when going bad.
 

Propilot

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If the engine is cranking fine (but the engine is not starting) it is probably is not an issue with the battery/starter solenoid/starter. I would first ensure that you have proper fuel pressure at the injectors when the engine is cranking. I would also check to make sure that the fuel pressure remains in the fuel rail after the key is shut off (it should maintain pressure for ~2-3 minutes after shutdown). A defective fuel pressure regulator or fuel pump check valve can cause the fuel pressure to drop after shut down resulting in a long crank time. I would also check fuel pump volume as this could also cause the same symptom.
 
Propilot said:
If the engine is cranking fine (but the engine is not starting) it is probably is not an issue with the battery/starter solenoid/starter. I would first ensure that you have proper fuel pressure at the injectors when the engine is cranking. I would also check to make sure that the fuel pressure remains in the fuel rail after the key is shut off (it should maintain pressure for ~2-3 minutes after shutdown). A defective fuel pressure regulator or fuel pump check valve can cause the fuel pressure to drop after shut down resulting in a long crank time. I would also check fuel pump volume as this could also cause the same symptom.
If I key on, but don't start, I hear the fuel rails pressurize. I'm pretty sure I hear them depressurize right after I shut the engine off though. I know I shut it off and restarted it in the same sequence right away and they had to repressurize.....will check that out.
 
If the MIL is commanded on there should be a DTC. It might be a "manufacturer" DTC, which maybe only a factory scan tool can see? Or an updated hi quality scan tool such as Snap On Verus?
 
06mach1 said:
If the MIL is commanded on there should be a DTC. It might be a "manufacturer" DTC, which maybe only a factory scan tool can see? Or an updated hi quality scan tool such as Snap On Verus?
Ford mechanic friend is coming by tonight and bringing his scan tool. I'm hoping his picks it up so we can narrow it down.
 

Propilot

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OBDII requires that all codes (both generic and OEM specific) be displayed on an OBDII code reader. As stated earlier, if you have an illuminated MIL, you should have a DTC. That being said (although I don't generally recommend parts stores to perform diagnostics), I would take your car to one that has a code reader and have them retrieve it. If you post the DTC here I can provide the OEM flowchart to diagnose it.
 
Propilot said:
OBDII requires that all codes (both generic and OEM specific) be displayed on an OBDII code reader. As stated earlier, if you have an illuminated MIL, you should have a DTC. That being said (although I don't generally recommend parts stores to perform diagnostics), I would take your car to one that has a code reader and have them retrieve it. If you post the DTC here I can provide the OEM flowchart to diagnose it.
Thanks for the input and hopefully his scanner will be able to find it. Should being the operative word. As we know this car has been known to throw CELs (flashing and static) and not leave a code even using the dealer's equipment.
 
Propilot said:
If the engine is cranking fine (but the engine is not starting) it is probably is not an issue with the battery/starter solenoid/starter. I would first ensure that you have proper fuel pressure at the injectors when the engine is cranking. I would also check to make sure that the fuel pressure remains in the fuel rail after the key is shut off (it should maintain pressure for ~2-3 minutes after shutdown). A defective fuel pressure regulator or fuel pump check valve can cause the fuel pressure to drop after shut down resulting in a long crank time. I would also check fuel pump volume as this could also cause the same symptom.
A little slow, but a light bulb just flickered when you mentioned the fuel rails. I noticed a weird smell when I went into the garage stall with the Boss last night and it just occurred to me that it smelled like Stabil. We'll be checking the fuel line tonight as maybe we didn't get it seated tightly........
 

Propilot

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With a fuel pressure gauge properly installed you fuel pressure should be:
KOEO: 35-77 psi
KOER: 27-41 psi

The KOEO pressure should be immediate after you turn the ignition to the RUN position.

Our vehicles have a Fuel Pressure Transducer that is located on the passenger side fuel rail. Look to see if the DTC (if you do indeed find one) is related to this sensor. If so then that is where your adventure begins. Do not assume that the issue is the sensor (it rarely is). As I said earlier, if you find a DTC (and your Ford Tech doesn't have access to a flowchart) I can provide you one. Good luck.
 
Propilot said:
With a fuel pressure gauge properly installed you fuel pressure should be:
KOEO: 35-77 psi
KOER: 27-41 psi

The KOEO pressure should be immediate after you turn the ignition to the RUN position.

Our vehicles have a Fuel Pressure Transducer that is located on the passenger side fuel rail. Look to see if the DTC (if you do indeed find one) is related to this sensor. If so then that is where your adventure begins. Do not assume that the issue is the sensor (it rarely is). As I said earlier, if you find a DTC (and your Ford Tech doesn't have access to a flowchart) I can provide you one. Good luck.
Thank you!
 
While it might not be related, there are some GT owners who have random long cranks, but the car starts up fine. I got that about once a month with the GT before the Boss. I don't think it has happened in the Boss, though. IIRC, there is a TSB for it?
 
WinterSucks said:
While it might not be related, there are some GT owners who have random long cranks, but the car starts up fine. I got that about once a month with the GT before the Boss. I don't think it has happened in the Boss, though. IIRC, there is a TSB for it?
Good to know. There's no TSB for it in the Boss as we checked yesterday. There is a TSB for potential chafing of the wires running to the fuel pump that could cause this but doesn't appear to be the case for me.
 
Update on the CEL. We hooked up the scan tool and software last night and had a string of DTCs. P0340,344, 345, 349, 365, 369, 390 and 394. They all indicated Cam Sensor Circuit faults on all four cam sensors. The VCT sensors showed no faults but VCT stayed in default mode even revving the engine so there was no VCT. After much consternation and a couple texts and phone calls to some very smart people we realized we had the cam sensors in the back of the head reversed. Whew! We were worried maybe some wires got accidentally crossed during the engine wiring harness upgrade which would have been no picnic to work through. So in the end, the CEL was related to the engine wiring harness and sensor upgrade and not the starting issue.

Anyway, the startup issue remains elusive as there were no other codes. I have noticed it's more prevalent when the vehicle is cold than when it's warmed up. For now we'll just see what happens after we move the battery. Who knows maybe we'll stumble onto a bad ground somewhere. As long as it starts and doesn't throw any codes I guess maybe it's just more of a gremlin. :-\
 

Grant 302

basic and well known psychic
Propilot said:
If the engine is cranking fine (but the engine is not starting) it is probably is not an issue with the battery/starter solenoid/starter. I would first ensure that you have proper fuel pressure at the injectors when the engine is cranking. I would also check to make sure that the fuel pressure remains in the fuel rail after the key is shut off (it should maintain pressure for ~2-3 minutes after shutdown). A defective fuel pressure regulator or fuel pump check valve can cause the fuel pressure to drop after shut down resulting in a long crank time. I would also check fuel pump volume as this could also cause the same symptom.

This^ With problems cranking, always go back to the basics...air, fuel, spark. An injector might be leaking. I'd also check all your plugs to see if on is different, wet or washed by fuel. If that yields nothing, I'd do a compression check while the plugs and COPs are off.
 
Grant 302 said:
This^ With problems cranking, always go back to the basics...air, fuel, spark. An injector might be leaking. I'd also check all your plugs to see if on is different, wet or washed by fuel. If that yields nothing, I'd do a compression check while the plugs and COPs are off.
I did pop in a fresh set of plugs when the coils were out and the harness and sensors were at PRS being upgraded. This cranking issue predates that so at least I know it's not plugs. Wouldn't a leaking injector pop a code?
 

Propilot

Support your local MS Society Chapter
Ok, so code issue is resolved....back to the long crank issue. As Grant 302 stated, time to go back to basics. Install a fuel pressure gauge and check fuel pressure. After installation of the gauge, roll the ignition key from OFF to RUN 2-3 times to prime the fuel rails. The pressure should be sitting in the 35-77 psi range. Before cranking the engine, turn the ignition key back to the OFF position and watch the fuel pressure gauge. The fuel pressure should not fall off significantly for 3-4 minutes. If this is the case you could have a check valve issue within your fuel pump, an injector(s)or the fuel pressure regulator.

If initial pressure is within specifications and the pressure holds I would then perform a fuel pump volume test. Let me know if you get to this point and I will see if I can locate a procedure and specification for you.
 
Propilot said:
Ok, so code issue is resolved....back to the long crank issue. As Grant 302 stated, time to go back to basics. Install a fuel pressure gauge and check fuel pressure. After installation of the gauge, roll the ignition key from OFF to RUN 2-3 times to prime the fuel rails. The pressure should be sitting in the 35-77 psi range. Before cranking the engine, turn the ignition key back to the OFF position and watch the fuel pressure gauge. The fuel pressure should not fall off significantly for 3-4 minutes. If this is the case you could have a check valve issue within your fuel pump, an injector(s)or the fuel pressure regulator.

If initial pressure is within specifications and the pressure holds I would then perform a fuel pump volume test. Let me know if you get to this point and I will see if I can locate a procedure and specification for you.
Excellent, thanks!
 
cloud9 said:
Update on the CEL. We hooked up the scan tool and software last night and had a string of DTCs. P0340,344, 345, 349, 365, 369, 390 and 394. They all indicated Cam Sensor Circuit faults on all four cam sensors. The VCT sensors showed no faults but VCT stayed in default mode even revving the engine so there was no VCT. After much consternation and a couple texts and phone calls to some very smart people we realized we had the cam sensors in the back of the head reversed. Whew! We were worried maybe some wires got accidentally crossed during the engine wiring harness upgrade which would have been no picnic to work through. So in the end, the CEL was related to the engine wiring harness and sensor upgrade and not the starting issue.

Not wanting to get off topic, but am considering the harness upgrade: were the cam sensors individually reversed or switched between cams?
 

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