Nuisance issue starting my F350

I am having a nuisance issue starting my F350 on cooler mornings and I’m only talking about temperatures in the low 40’s so far. It was doing this when I first bought it back in January last year. I could plug in the block heater and it would start up with no problem so I took to a local Ford dealer. They replaced the “O” rings on the injectors and replaced the under the valve cover harnesses. It would fire right up and I could tell there was a noticeable improvement in performance. Now with the cooler mornings here it’s doing it again. I can plug up the block heater and it starts right up. Any ideas on what the problem is? I also replaced the glow plug relay last year too.


Glow plugs maybe? How difficult is it to change them out? I definitely don’t want to go back to the dealer, their labor rates are $125 an hour!

Sounds like injectors. Runs bad and slowly gets better as the truck heats up?

No, it runs fine right after start up. Just hard to get started with the cooler temps.

I'd check all of the sensors to see if any are bad and have defaulted to some sort of failsafe setting.  I had an oil temp sensor that went bad, an intake air sensor that went bad and something else.  One made a huge difference.  No codes though.  Found it by using a scanner and comparing the scanner readings to the temp gun in hand...  I also had a problem with the starter being somewhat bad and sucking too much voltage to start the truck. Are the glow plugs themselves known to be good?

Glow plug relay might be bad the one you get at most local auto parts don't last long. I had to change mine again I also changed mine over to manual this time that way it I only heat the glow plugs when I need to in cold weather.

I only charge 651 dollars an hour when I work on one over the internet......

69F100 wrote:Glow plug relay might be bad the one you get at most local auto parts don't last long. I had to change mine again I also changed mine over to manual this time that way it I only heat the glow plugs when I need to in cold weather.

I don't think it's the relay. I didn't buy one from the local auto parts store, I got this monster. http://www.dieselorings.com/16-009-white-rodgers-stancor-586-902-monster-glow-plug-relay.html

Volt drop across the relay when activated, should be less than .5 volt, then ohm each glow plug at the valve cover connector.... Between tbe wide pins and ground, should be under 2 ohms.

I'm going to assume it's a 7.3??? Check the basics first...Test all the GP's to make sure they are good, make sure the relay is actually closing too. Only use GP's from the dealer that say BERU on the side if you want them to last. I'm working on an 02 F350 for a racing buddy right now - all 8 were dead and it started fine until it got cold out. Badly worn injector's can act like this too, usually a buzz test on a cold engine can lead you to the bad ones. Changing the GP's is easy on a 7.3, getting the valve covers off is more work then changing the GP's.

BigRigTech wrote:I'm going to assume it's a 7.3??? Check the basics first...Test all the GP's to make sure they are good, make sure the relay is actually closing too. Only use GP's from the dealer that say BERU on the side if you want them to last. I'm working on an 02 F350 for a racing buddy right now - all 8 were dead and it started fine until it got cold out. Badly worn injector's can act like this too, usually a buzz test on a cold engine can lead you to the bad ones. Changing the GP's is easy on a 7.3, getting the valve covers off is more work then changing the GP's.

? when you guys change the valve cover gaskets do you glue them or put them dry. 7.3

I put them on dry.

Its a reusable gasket no goo required

richter69 wrote:Its a reusable gasket no goo required

That's way i put mine about 6mounths ago & there leaking now. so what you just have to tighten the screws every few months?
to keep them from leaking? or locktite the screws.

res0rli9 wrote:

richter69 wrote:Its a reusable gasket no goo required

That's way i put mine about 6mounths ago & there leaking now. so what you just have to tighten the screws every few months?
to keep them from leaking? or locktite the screws.

Valve covers are warped or the bolt hole area is pushed in a little from over tightening and wont allow cover to seal properly.

Although it's pricey, I'm thinking about getting the Auto Enginuity Scan Tool-PC based with the Total Ford Enhanced Package that I can install on my laptop. I can also use this on my Ranger since I keep having a check engine light that comes on depending on the weather. In researching my problem I read about this on several other diesel forums and it sounds like a pretty good product.

It will perform the following tests, some are not relevant to my truck but seems to be a pretty comprehensive list.

PATS Timed Key Programming ('96 - '08)
KOEO
KOER
Power Balance (CAN-based models)
EVAP Bay Test
Service Bleed (Non-CAN support not available with ProLine currently)
Buzz Injector
Cylinder Contribution Test
Switch Test
Glow Plug Test
System Self-Test
Low - and High Speed Fan
All Outputs On/Off
Injector Coding (1.8L and 2.0L)
KAM Reset
Misfire Monitor Neutral Profile Correction
Tire Size Programming up to 40" ('99-'03 7.3L, and '04-'07 6.0L trucks)
IVD Initialization
Steering Angle / Yaw Rate / Acceleration Sensor Reset ('03 Explorer and Lincoln LS)
Passenger Seat ReZero and Passenger Weight Reset
Power Seat Calibration Test
Audio Network Communication Test
Vehicle In-Motion IO Test
Front Wiper Self-Test
Rear Wiper Self-Test
Diesel Particulate Filter Reset, Clear EGR Adaptive Tables, and Clear Fuel Injector Adaptive Tables

I have it on my laptop...works awesome. Great for the diesel stuff, tests and live data.

BigRigTech wrote:I have it on my laptop...works awesome. Great for the diesel stuff, tests and live data.

Cool, I'll order it right away. I'm sure family and friends can get some use out of it too.

Worth every penny to me. Nice for ABS troubleshooting too. It will show wheel speeds.