Truck just died (I have searched these forums and done all the obvious)

[OverKill73]

Hey guys,

I have been searching forever and doing everything I can related to my problem that was posted on this site, and I still have a dead truck.

I was driving down the road earlier this week at 70 MPH when my 99.5 7.3 truck just quit. No sputter, no smoke, no warning lights, it just quit like I turned the key off.

I have dropped the fuel tank, made sure there was nothing in there blocking the pick up, checked my oil level, tested the electric fuel pump below the driver's seat on the frame rail, noted that there is fuel in my fuel bowl on top of my HPOP, replaced the CPS, replaced the IPR, and it still cranks but won't fire! I tried for the fun of it shooting ether in the intake (after taking the boot off) and it starts right up until the ether runs out. I know this isn't a good idea, but It was one of my desperate moments that I won't do again.

Any ideas as to why my truck won't start?

You guys are amazing, and I have seem just about every issue I could think of be diagnosed on this site.

Thanks in Advance,

- Mark

[klhansen]

Are you sure you're getting power to the PCM? Does the WTS light come on when you turn the key? If the fuel bowl heater shorts and blows fuse #30, the PCM won't get any power. Pull the fuel heater connection, replace the fuse and try again.

At this point, I'd be checking all the fuses with a meter to see what's up with them. If the IDM relay stopped working, it would kill the engine also, but I think it would light the Check Engine Light.

[OverKill73]

KL,

I just checked all the fuses, and replaced # 30 (which I believe is actually a relay) and no luck. I still get the WTS light, but still it won't fire. Any other suggestions? I will also look though your hyperlink of possible solutions.

Thanks for your help here, I really appreciate it!

[klhansen]

That link in my sig is for GP system problems, which I doubt you're having.

Fuse 30 would be under the dashboard, #30 under the hood is the PCM power relay (furthest rear toward the driver's side).

You might try swapping the IDM relay (third from the rear) out with the heater fan relay (second from the rear) to see if that's your problem.

If that doesn't work, you'd be better off getting a scan, and even better a scan tool that monitors parameters and while cranking, monitor battery voltage, ICP, IPR duty cycle, injector pulse width.

Another shortcut you might try is unplug the ICP sensor (behind the alternator on the head) and see if it starts. If the ICP sensor is biased high, the PCM would think that HP oil pressure is too high and tell the ICP to dump pressure. If it doesn't get to 500 psi on the HP oil system, you won't be starting.

[F350_6]

Did you refill the HPOP reservoir after you replaced the IPR? Low oil in the reservoir can cause a no start. You can check the main engine wiring harness (big one that comes up and over the drivers valve cover) for chaffing against the valve cover or CCV bracket, but I agree with getting it on a scanner, preferably one that can monitor live data while cranking.

[OverKill73]

Chris,

I know this is going to sound stupid, but how do I check the HPOP resivor? I also just hooked a mac scan tool that had the software for my truck and it came up with a code that said bank a cam position sensor low voltage. I see that the tach cranks when I hit the starter, and it doesn't when I disconnect the connector to the CPS, but I wonder why I am getting that code.

I also swapped the IDM relay and checked the #30 fuse under the dash, and also unplugged the IDP sensor. Still no luck

Also, something worth mentioning that maybe I needed to the more I think about it. I have a small oil leak under the truck that I can't identify. I have looked the best I can, but it's coming somewhere deep from the engine. It has been leaking for a couple months, and I just keep adding oil when I need. It uses maybe 1 quart every 2,000 miles. I think it may be a rear main, but I am not certain. Could this possibly have something to do with it not starting?

[97powerstroker]

the hpop resovouir is on the front of the engine under the powerstroke cover,its a rectangular resovour,there will be a allen head plug on the top,drivers side of it.take it off,and stick a screw driver or something in it to determine how close the oil is from the top,it should be right up at the top.my guess is that the idm itself is bad,this drives the injectors so when it kicks the bucket,game over right there.thats my best guess.good luck

[97powerstroker]

one more thing is the new cps u bought,could be bad,ive heard of this happening more then u would think,so if u have an extra 20 or 30 bucks,pop another one in,it may suprise ya and start.i bought a new one awhile back and it only lasted a month,then i bought the gray one and it solved the problem.definitly check your oil! goodluck again

[F350_6]

The injectors fire off of engine oil, so if it gets too low the truck won't run. I doubt this is your problem. I'd also be surprised if your rear main seal is leaking. Grab a flashlight and check the engine valley (up on top of the motor between the 2 heads) for any signs of oil. If you've got a really slow leak, check the orange boots on the bottom side of the spider. My experience is the passenger one tends to work it's way loose and will cause a small oil leak that may not give you any signs of drips. If you can't tell the boots are orange by looking at them, they need to be tightened.

There is an inspection plug on the HPOP reservoir (T-20 I think). Remove the plug. The engine oil should be within 3/4" from the top.

Edit: Also tell us what code your scanner pulled so we have a better idea of what you're dealing with.

[OverKill73]

Chris,

Thanks for the info. I just let my buddy go, I should have written down the codes, but what I remember is that the MAC scan tool came up with fuel pressure circuit low, and then cam position sensor bank A low voltage. I am going to have him back on Monday to get the exact codes we were seeing so I can provide you guys with a little more exact details. Thanks for your help!

- Mark

[OverKill73]

97 Power, where is the IDM located? I replaced the IPR, but I don't think the IDM was inside of that. Also the HPOP reservoir is full.

Chris, thanks for the diagram, that was really helpful!

[haul_n_horses2]

Originally Posted by F350_6

Did you refill the HPOP reservoir after you replaced the IPR? Low oil in the reservoir can cause a no start. You can check the main engine wiring harness (big one that comes up and over the drivers valve cover) for chaffing against the valve cover or CCV bracket, but I agree with getting it on a scanner, preferably one that can monitor live data while cranking.

I doubt a low HPOP reservoir is going to make it die going 70 mph down the road. Sounds electrical, fuses, shorts etc. Scan it and get the soft codes.

[F350_6]

Originally Posted by haul_n_horses2

I doubt a low HPOP reservoir is going to make it die going 70 mph down the road. Sounds electrical, fuses, shorts etc. Scan it and get the soft codes.

I agree, but I'd hate to think that changing the IPR drained the oil level in the HPOP and prevented him from finding his issue. If the IPR was the reason for the stall, then he just needs to top off the HPOP.

I also think this sounds electrical, but no point in trying to chase that problem if you have an empty reservoir. You'll never know what fixed the problem.

[OverKill73]

Guys, can you tell me more about the IDM and where it is located?

I will grab my neighbor's Mac scan tool on Monday. He is at a car show today, but I should be able to give you exact codes on Monday.

Thanks!

[F350_6]

The IDM (Injector Driver Module) is what energizes the injectors, and after receiving input from the PCM & CPS makes sure they fire in the right sequence for the motor to run. It's a box hidden above the drivers front wheel well liner kind of behind the F250 badge on your fender.