TPS ? Fuel Pressure ? What You think ?

[MrMarty51]

Real hot out, probably 110* F or so.
Twice on one drive, in town, about last Monday, 35mph. Give the foot feed a little throttle, not a lot, let off and it seemed like the engine near died but then picked back up again.
About a half a mile later it did the same thing.
I thought WTF but no real clue. The second time it was like the SES lamp may have popped on but immediately off again, just a mighty fast flash.
Then Friday, driving along, approaching a stop sign, released the foot feed pedal, went to stop. Brake pedal hard to push, my immediate thought was, brakes gone to ?
Pumped the pedal and still tough to get stopped. By the time I got stopped was when I noticed that the engine had stalled.
Twisted the key to start and not a fire, turned key to off then back to on, WTS lamp illuminated, twist to start position, fired right up and away I went.
Drove directly to home with the brake light switch for the Buick and got that installed so We’d have that car for a spare.
Started the truck, observed the fuel pressure. When I first installed this GlowShift FP gauge and sender unit the FP was running 9 PSI on the Carter pump and relay system from Leroy Diesel.
I didnt have the gauge hooked the first go round of when the engine seemed to die.
Friday morning though I noticed that the FP was running about 4 pounds.
Just what the FP was when the engine did stall I did not have a look at the gauge until I got it fired up again, about 4PSI.
While the truck was idling at the house, there is absolutely no air intrusion in the clear plastic hose.
Probably going to take several shots at it with the parts cannon.
1: New A/C Delco ignition switch.
2: New Throttle Position sensor.
3: New Air Dog fuel pump system from QuadStar tuning.
Guess I’ll be shedding some tears at 3 but I’m trying to get this truck to be as dependable as any 6.5 on the road and the over priced fuel pump system is a part of that.
I was going get started to pull the engine as soon as the grand sons left, but then, when we all were at the sons house for supper before the grand sons took back to home in Alaska, my son informed me that his wifes Continental X had sprung a coolant leak, coolant pump leaking internally into the engine.
Yup, freaking ford mounted the coolant pump inboard of the engine so when it goes to crap it wipes out the bearings in the engine.
Kelly told Me that the engine had to be pulled to replace the coolant pump. The shop charge was in excess of $4,000.00 to pull, fix and reinstall the engine, so now, He and I will be doing the job so my truck job will be on hold for another two or three weeks.

 

[jrsavoie]

Real hot out, probably 110* F or so.
Twice on one drive, in town, about last Monday, 35mph. Give the foot feed a little throttle, not a lot, let off and it seemed like the engine near died but then picked back up again.
About a half a mile later it did the same thing.
I thought WTF but no real clue. The second time it was like the SES lamp may have popped on but immediately off again, just a mighty fast flash.
Then Friday, driving along, approaching a stop sign, released the foot feed pedal, went to stop. Brake pedal hard to push, my immediate thought was, brakes gone to ?
Pumped the pedal and still tough to get stopped. By the time I got stopped was when I noticed that the engine had stalled.
Twisted the key to start and not a fire, turned key to off then back to on, WTS lamp illuminated, twist to start position, fired right up and away I went.
Drove directly to home with the brake light switch for the Buick and got that installed so We’d have that car for a spare.
Started the truck, observed the fuel pressure. When I first installed this GlowShift FP gauge and sender unit the FP was running 9 PSI on the Carter pump and relay system from Leroy Diesel.
I didnt have the gauge hooked the first go round of when the engine seemed to die.
Friday morning though I noticed that the FP was running about 4 pounds.
Just what the FP was when the engine did stall I did not have a look at the gauge until I got it fired up again, about 4PSI.
While the truck was idling at the house, there is absolutely no air intrusion in the clear plastic hose.
Probably going to take several shots at it with the parts cannon.
1: New A/C Delco ignition switch.
2: New Throttle Position sensor.
3: New Air Dog fuel pump system from QuadStar tuning.
Guess I’ll be shedding some tears at 3 but I’m trying to get this truck to be as dependable as any 6.5 on the road and the over priced fuel pump system is a part of that.
I was going get started to pull the engine as soon as the grand sons left, but then, when we all were at the sons house for supper before the grand sons took back to home in Alaska, my son informed me that his wifes Continental X had sprung a coolant leak, coolant pump leaking internally into the engine.
Yup, freaking ford mounted the coolant pump inboard of the engine so when it goes to crap it wipes out the bearings in the engine.
Kelly told Me that the engine had to be pulled to replace the coolant pump. The shop charge was in excess of $4,000.00 to pull, fix and reinstall the engine, so now, He and I will be doing the job so my truck job will be on hold for another two or three weeks.

I'm sure I don't need to say it,

Make sure you have plenty of fuel available to the lift pump.

 

[MrMarty51]

I'm sure I don't need to say it,

Make sure you have plenty of fuel available to the lift pump.

Tank sock has been removed.
Maybe I should change the 3/8ths inline steel canister filter ahead of the LP to be sure.

 

[Twisted Steel Performance]

Loosen the fuel cap...

 

[JayTheCPA]

If loosening the fuel cap works, then time for a new cap.

If not, any other restriction points such as inline filters? Crimped hard supply line? Imploded soft supply line?

Can try the trick of forcing air back into the tank to see if it was a simple clog. Make sure to loosen the tank cap just for precaution.

 

[MrMarty51]

I’ll be trying alla these suggestions, one atta time though. Just so if one of tjese works it will be one of them AH HA moments.

 

[Will L.]

Ok, ya know I always push the big boy lift pumps- but that will NOT solve this right now.

You had 4psi. At 4psi you might be missing out on 5-10% power under the most extreme circumstances. But you would not experience what you were because of 4psi rather than say 8 or 10psi. The problem with changing parts that are not proven bad is you can create a new issue by mistake- imagine the new LP is defective or a bad connection starts allow intermittent air intrusion.

Please show. Pic of where exactly your pressure gauge is tapped.

Remember the final screen that exists could be plugging.

 

[WarWagon]

Any codes?
Normal but note: SES may illuminate on low RPM or stalling, but, if the engine RPM comes back up it goes back out.
Glow plugs on a hot engine make me want to check power to the ECM including grounds and bad batteries. However if the key wasn't "OFF" for 30 seconds the ECM was still alive and the SES/ STS lamps become unpredictable.

MY experience with your symptoms was a hidden kinked fuel line behind and feeding the FFM under the wiring harness. A big boy pump may push fuel past this restriction like it did for me awhile. However it wasn't the real problem. On engine stall the return line was clear: no fuel in it at all.

 

[MrMarty51]

Connected to the Autel Maxi200. Took a while, it run through some updates.
Got in and checked for codes. Told me no codes.

Did some exploring within the program and dont know how but then this one comes up.

Lost communication to the PCM or ECM.
See how tomorrow goes, if I’m not too tired after work then I’ll pull the grounds at the back of the head and see whats going on back there.
I did pull the pre IP fuel filter, drained and blew through it.
A slight bit of resistance but nothing I’d consider performance altering.
Installed a new filter and pressure increased from four or five pounds to near seven.

And the plumbing pre FFM.

I do have a switch setting at the NAPA store.
It is listed as on-power-on.
The two on positions on each end will go to each sending unit and the center power terminal to the gauge.
I need to remember to pick that up tomorrow.

 

[MrMarty51]

Might be that when I was hanging that fuel plumbing that maybe There was a wire that is compromised and got stretched to where now it might make and break connection.

 

[MrMarty51]

Ground wires all solidly mounted to ring terminals. Removed nut and inspected.
Main ring terminal had some black, stainless wire brush and cleaned them all to bright and shiny. Scrubbed on the stud and nut face too. Applied a smear of truck lite anti corrosion grease and reassembled.
Set up the Autel app and drove the truck to work.
Fuel pressure back down to between two and four pounds but no codes tripped and the enjun did not die in the couple miles to work.
I hope itiz fixed.

 

[MrMarty51]

A total of about 15 miles today.
The enjun never did stall or die.
I am praying and hoping that this problem is solved.
I do so bad want to go for the AirDog fuel pump system from QuadStar tuning but with the oil leak and items I would like to attend to while the engine is out is going to tack my home systems to the maximum.
Wifey thinks, sell all our vehicles and get just two, or one, she has an 08 Malibu with just 90,000 miles on it.
I’m like, I aint done spending money on my 6.5 yet so you just hold onto Your horses.
I want this engine sealed up and at least as phar as gapless rings and new bearings, along with the timing gear set and I’m sure I can think of a lot more items to buy to keep me, and my truck, happy.

 

[jrsavoie]

A total of about 15 miles today.
The enjun never did stall or die.
I am praying and hoping that this problem is solved.
I do so bad want to go for the AirDog fuel pump system from QuadStar tuning but with the oil leak and items I would like to attend to while the engine is out is going to tack my home systems to the maximum.
Wifey thinks, sell all our vehicles and get just two, or one, she has an 08 Malibu with just 90,000 miles on it.
I’m like, I aint done spending money on my 6.5 yet so you just hold onto Your horses.
I want this engine sealed up and at least as phar as gapless rings and new bearings, along with the timing gear set and I’m sure I can think of a lot more items to buy to keep me, and my truck, happy.

We have 4 vehicles and seem to have trouble with having one vehicle to drive, at any given time.

Some family member often have one of the vehicles. One or more of the other 3 all seem to need something all of the time.

No matter which vehicle is loaned out.

 

[MrMarty51]

We have 4 vehicles and seem to have trouble with having one vehicle to drive, at any given time.

Some family member often have one of the vehicles. One or more of the other 3 all seem to need something all of the time.

No matter which vehicle is loaned out.

Yup. All the time something going on with any nummer of vehicles.
IDK if GlowShift gauges is any good.
I was questioning the low fuel pressures.
Today, this morning, driving the truck to work. Fuel pressure gauge started bouncing all over the numbers.
0 to 35 PSI and everything in between. Continued from shortly after leaving the property to when I got to working area.
Probably going to have to send those back, hope to get a refund and maybe see if there is a good old fashioned Stewarrt Warner electronical fuel pressure, or oil pressure, gauge available.

 

[jrsavoie]

Yup. All the time something going on with any nummer of vehicles.
IDK if GlowShift gauges is any good.
I was questioning the low fuel pressures.
Today, this morning, driving the truck to work. Fuel pressure gauge started bouncing all over the numbers.
0 to 35 PSI and everything in between. Continued from shortly after leaving the property to when I got to working area.
Probably going to have to send those back, hope to get a refund and maybe see if there is a good old fashioned Stewarrt Warner electronical fuel pressure, or oil pressure, gauge available.

Does the gauge need a snubber?

Let us know when you have a gauge working properly.

How were the reviews on the Glow shift?

 

[royunion]

Really - 4 psi is just killing the IP.

Get a lift pump that can push 15 psi regulated and the problem will go away.

I saw IP come into the shop all time for rebuild running low fuel pressure with scratches all on the internals.

5 psi regulated + or - 1% is the test spec minimum the IP should operate at, but driving like that just kills the IP.

See my post starting backwards at https://www.thetruckstop.us/forum/threads/fuel-problem.52008/post-679522

 

[SnowDrift]

Wouldn't the pressure be best tested after the FFM?

 

[Twisted Steel Performance]

Yes

 

[jrsavoie]

Wouldn't the pressure be best tested after the FFM?

If I get to it, I'm going to install 2 sending units.

One before the FFM

And one at the IP.

Or the next guy can do as he pleases

 

[MrMarty51]

Really - 4 psi is just killing the IP.

Get a lift pump that can push 15 psi regulated and the problem will go away.

I saw IP come into the shop all time for rebuild running low fuel pressure with scratches all on the internals.

5 psi regulated + or - 1% is the test spec minimum the IP should operate at, but driving like that just kills the IP.

See my post starting backwards at https://www.thetruckstop.us/forum/threads/fuel-problem.52008/post-679522

I do have a 60 PSI fuel pump. Made for gasoline. I also have a MrGasket adjustable fuel pressure regulator. Left overs from my days of trying expirememntals of converting the 1978 MGB over to FI.
The pump is an inline but IDR what brand. Gottit from NAPA. IIRC.
Would that be better suited for the 6.5
I think a pump made for gas should be okay to push diesel fuel ?
Also. My plans are to pull the engine, that project keeps getting pushed off.
Now it is going to be another two more weeks, at least. The sons wifes lincoln X needs a coolant pump. Hoping to not have to pull the enjun for that, as is recommended. Seems though it is possible without going through alla dat so it might be done before this weekend is over.
If so then I’ll be on pulling this 6.5 before next weekend.
See how much damage I can do to the CC before this job is finished.
I think before it is all said and done an AirDog will be in the workings too.
Gapless rings and bearings too.