7.3 no start

[Denver]

I have a no start problem on my 7.3. Truck is a 2002 F250 7.3 4R100. 268K miles and a West coast truck. Valve covers never been off but I know the injectors and HPOP are good. Anyways it has a no start condition. Not a hard start, but no start as in injectors not firing. Turns over just like normal but doesn't start.

A note and some recent history. It's always had a longer start than other 7.3's I've been around. Last Saturday I remove the driver side battery to measure the intercooler end. When I fired the truck up I didn't wait for the dash to complete its gauge sweep cycle after the battery removal. Same day I sprayed simple green on the intake Y and surrounding areas because I'm going to change the CAC and valley boots and lightly hosed off the dirt and oil. I first then started the truck the next day and it started fine. Morning after that it's 38* out and first crank it didn't start. Second crank it fired up. Got to work and 8 hours later and now mid 70's weather no start, just turn over. Replaced the CPS with a black and same symptoms. Wiggled some wires and 10 minutes later it fired up like normal.

3 days it's running fine and normal until this morning. Mid 40's this morning and no start. Put a volt meter on the batteries and key on, engine off it shows 12.5 volts then drops to 11.7 volts for GP. Turn the engine over it drops to 11.4 to 11.1. Did about 30 seconds of cranking in cycles then it went to 8 volts. Later that day and no charging the batteries, I tried starting it again and got the same voltage readings. Then the batteries got weak again. Tried jump starting it from another 7.3 and no start.

Oil pressure is good. ICP is dry and good and wouldn't start unplugged. Fuel pressure is good. Fuses are good and relays are good. Only thing I can think of is the IDM or there is a large current draw on the batteries. The batteries are charging at the moment separately and will try again in the morning. Years ago I had a starter go bad from washing oil off it and it caused it to pull a lot of current.

The problem is an intermitted problem. It's a start or not going to start. It's not a hard start condition. What else should I look at?

 

[79jasper]

Wiring around the fuel bowl going to the ipr.

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[Arisley]

12.5 volts is low. How old are the batteries.

 

[Denver]

12.5 volts is low. How old are the batteries.

1 year and Motorcraft batteries. The truck lives in Arizona. These batteries have seen hot summer heat, like 100+ and up to 120 for 4 months. Now it's been cold at nights. High 30's to mid 40's at night. Batteries don't live long here. I'm going to get them load tested. What I found strange about diagnosing this no start is the starter turns over just fine then 20-30 seconds in to it struggles for 2 seconds like low batteries then just goes to 8 volts while cranking. Can a bad IDM cause an intermitted no start condition?

 

[dmd]

Any smoke out the exhaust when trying cold start?

 

[Denver]

Any smoke out the exhaust when trying cold start?

No smoke. I'm 90% sure this is a, something not communicating electrical wise.

 

[dsberman94]

Sounds like mine when the IPR started to go bad. Do you have pcm connection? All lights on dash acting normal.

 

[lincolnlocker]

12.5 volts is low. How old are the batteries.

Not running they are 12.5v.

live life full throttle

 

[lincolnlocker]

How do you know hpop and injectors are good? Whats icp and ipr dc while cranking?

live life full throttle

 

[Denver]

How do you know hpop and injectors are good? Whats icp and ipr dc while cranking?

live life full throttle

It's always been a dry climate truck, meaning no moisture gets in the fuel or oil. It's my personal truck and am OCD about the oil, fuel, and air being clean and changed every 5k. Completely stock truck that is a 65 mph daily driver.

 

[lincolnlocker]

It's always been a dry climate truck, meaning no moisture gets in the fuel or oil. It's my personal truck and am OCD about the oil, fuel, and air being clean and changed every 5k. Completely stock truck that is a 65 mph daily driver.

268k on a heui motor is a lot bud. Id be real surprised if it wasn't the hpop or injectors. But with that said, whats the answer to the second part of my question?

live life full throttle

 

[lincolnlocker]

What oil has it had in it all its life?

live life full throttle

 

[Denver]

So the truck started and runs fine... after some no start tries. Here's what I got.

Had a battery tender on each battery over night and into this afternoon. Had a green light on both. Each showing 12.5 volts now. Seems low but whatever. Hooked them up and go to start and just turns over but doesn't fire. No smoke out the exhaust. Had the volt meter on the driver side battery and key off voltage is 12.3. Key on engine off voltage went to 11.3. Key on starting went to 10 then after 3 cycles went to the 8's.

So now I unplug stuff one at a time and try to start, then plug back in after trying to start. Unplug the EBPV plug on the pedestal and no start. Unplug the ICP sensor and no start. Wiggle the valve cover harnesses and no start. Wiggle the IPR and no start.

Early on I noticed a 1 to 1.5 volt drop with key on engine off. I went to another 7.3 that is at operating temp and it doesn't have but maybe a .5 volt drop between key off and key on engine off. When starting it went into the high 11's.

Something is pulling power. The glow plug control module (California Truck) feels warm. I swap in a bad one and still get the voltage drop and no start. Reinstall the good one. Now I unhook the alternator wiring and plug on it and still get a voltage drop and no start. Turn the key off and grab a SCT X3 to read codes and alternator still unplugged. Turn key on engine off and volts drop into mid 10's but didn't try to start, just get codes. Came up with P0475, P0603, P1000, P1280. So now I'm reading the code description on the SCT and writing the codes down. Takes some time... I look up at the volt meter and have 12.12 volts. Figured its over 12 and turn the key to start and it started right up just like it always has for the past 18 years. Let it run for 3 seconds and shut it off and then restart with no glow plug cycle and it starts up just fine and volts were between 11.5 to high 8's while cranking and still started. Reconnect the alternator and it started right up and charging volts are 14.1. Did about 3 more starts and is back to normal.

Now here's where there is still something going on. The first 4 key cycles there is something pulling power. With the key off volts are low to mid 12's. Key on engine off the volts start at 11.5 and go into the mid 10's. After a minute, and I timed it, the volts come back up to the 12's like a switch is flipped. After the 5th key cycle the volts were staying in the 11's with key on engine off, until that 1 minute mark. What is on these trucks that has a 1 minute cycle once ignition is turned to on? Fuel pump is like 15 seconds, Glow plugs seem about 20 seconds (after engine starts) but don't know the cycle time with engine off.

I know I still need to get the batteries load tested but is there anything in my novel here that can lead me to the culprit?

 

[Denver]

268k on a heui motor is a lot bud. Id be real surprised if it wasn't the hpop or injectors. But with that said, whats the answer to the second part of my question?

live life full throttle

268K isn't much really. I don't have the tooling to read what your asking for, for the second part of your question.

What oil has it had in it all its life?

live life full throttle

Birth to 50K IDK as I'm second owner. 50K to 200K was whatever Ford or the local diesel repair place used. 200K on has been travelers 15-40 from TSC. It's always had motorcraft oil and fuel filters.

 

[lincolnlocker]

268K isn't much really. I don't have the tooling to read what your asking for, for the second part of your question.







Birth to 50K IDK as I'm second owner. 50K to 200K was whatever Ford or the local diesel repair place used. 200K on has been travelers 15-40 from TSC. It's always had motorcraft oil and fuel filters.

Im having convulsions over here..... bottom of the barrel **** there. Dint he surprised if its injectors or hpop... you need to find someone with a scanner to read what i asked....

live life full throttle

 

[Denver]

Im having convulsions over here..... bottom of the barrel **** there. Dint he surprised if its injectors or hpop... you need to find someone with a scanner to read what i asked....

live life full throttle

I'm not here to argue what you think is bad based on mileage or oil used. It's unrelated to the problem I'm trying to diagnose. I'm having an electrical issue. Not a tired or worn out HPOP or injectors problem. It's clear the truck will start or will not start. There is no in-between problem like it's struggling to start. Sometimes the system is telling the injectors to fire and sometimes the system is telling the injectors to not fire.

As for the oil, it has crossed my mind if its a good oil or not but got past the mindset that just because it comes from TCS doesn't make it a bad oil. It's on Fords approved list unlike Delo. It's been running in this truck for 70K miles. It's been running in another truck for 150K miles and that truck has more overall miles. I've ran Lubrication Engineers oil for about 30K miles and honestly didn't notice anything different.

 

[lincolnlocker]

I'm not here to argue what you think is bad based on mileage or oil used. It's unrelated to the problem I'm trying to diagnose. I'm having an electrical issue. Not a tired or worn out HPOP or injectors problem. It's clear the truck will start or will not start. There is no in-between problem like it's struggling to start. Sometimes the system is telling the injectors to fire and sometimes the system is telling the injectors to not fire.



As for the oil, it has crossed my mind if its a good oil or not but got past the mindset that just because it comes from TCS doesn't make it a bad oil. It's on Fords approved list unlike Delo. It's been running in this truck for 90K miles. It's been running in another truck for 150K miles and that truck has more overall miles. I've ran Lubrication Engineers oil for about 30K miles and honestly didn't notice anything different.

Alright bud.. hopefully you are right...

live life full throttle

 

[Addicted4]

Get a scanner on it and report back icp, ipr duty cycle, and rpm while cranking, Volts while cranking. May have a idm, cam sensor, hpop related or injector issue, oring problem but without the scanner data we are all shooting in the dark and sharing our own personal issues with our trucks not yours.

Mileage doesn’t mean much if maintained. 326k on my engine and never been apart. Original injectors but had the hpop gone thru for lower than desired icp and back cover weeping oil.

 

[Denver]

Get a scanner on it and report back icp, ipr duty cycle, and rpm while cranking, Volts while cranking. May have a idm, cam sensor, hpop related or injector issue, oring problem but without the scanner data we are all shooting in the dark and sharing our own personal issues with our trucks not yours.

Mileage doesn’t mean much if maintained. 326k on my engine and never been apart. Original injectors but had the hpop gone thru for lower than desired icp and back cover weeping oil.

Thanks for the reply. I do not have a scanner. I wish I did and may look into one now. I gave the best description I could with the tooling I have and best diagnosing to my knowledge. I understand the forums are a place of advice and not a guaranteed solution to the problem but being told it's something else unrelated because of the mileage doesn't really help anything given my earlier descriptions.

Starting the truck is a procedure now, when it's acting up. If I get in and turn the key to start, it will just turn over and not start. If I turn the key to on, engine off and wait a little more than a minute, then turn the key to start it will start in less than 2 seconds or just like normal.

This is why I'm leaning towards an electrical issue. Key on engine off the volts start at 11.5 and go into the 10's and no start, just spin. With key on engine off again, it's 11.5 and gets into the 10's and if I wait a little more than a minute with key on engine off the volts go from mid 10's to low 12's like a switch is flipped and it will then start and run.

 

[dsberman94]

Because after a minute the GPCM turns off the glow plugs and your voltage comes back up. Battery when not running should be between 12.4 - 12.9, so you’re within range there, a little on the low side but in there. The significant drain might be one of the batteries being bad. Disconnect them from the truck and each other and let them sit overnight, if they aren’t close to the same voltage in the morning you know which one is bad. Check that with a meter on each battery. The low voltage while the GPCM is active might be draining it too far for the pcm/idm to be happy and fire the injectors. Could be fuel pressure related as well. The pump runs when you turn the key to run but will shut off in a few seconds. That wouldn’t cause a 1 minute delay on voltage though.

Sorry Jake but not sure the oil used is the culprit this time unless icp and ipr duty are terrible but it seems to much like and electrical issue for oil to make sense. Again could be low icp but I believe he already ruled that out by unplugging it to default to whatever the number is that will allow the pcm to fire the injectors. I don’t remember the psi ATM, too many drinks in.

Really that truck should start in 70 degrees with no glow plugs. 38 degrees on a healthy engine it should still hiccup. Might run like chit but it’ll at least catch on a cylinder or two.

Going to do some out loud thinking here. Sorry if you e already tried some of these.

I would start with checking each batteries after sitting overnight disconnected from the truck and isolated from each other.

IPR issues, tin nut on the back could be loose. Coil could be going bad. I got away with just changing the coil on mine and it’s working great years later. Wires frayed or broken but again probably wouldn’t be solved with a minute of KOEO. Something sticky in the ipr could do it though and it needs the extra bit of juice to make it work.
Icp sensor new from Ford or parts store? Ford is the go to for it if you get it from anywhere else it’s probably junk.

Fuel bowl heater fuse piggy backs pcm power. Fuse could be blown but 1 minute wouldn’t solve that either.

After checking the batteries, If it’s warm enough that you don’t have to let the glow plugs work, if there’s a way you can unplug the GPCM and try to start it immediately after turning the key on that could help also. I’m more familiar with a relay system than the module. Firc I believe glow plugs stay active even after the pcm turns the dash light off. I think it’s 60-90 seconds total.