# 7.3 diesel stall



## Doc Holliday (Mar 12, 2011)

at red light, in gear with foot on brake, truck stopped: truck slightly romps (idle goes slightly up and down repeatedly between 600-800 appr.) and will stall. Only thing keeping it from stalling is my chip which I have to set on high idle (constant 1250 rpm's without stalling) until light turns green. Happens in reverse as well.

New Garrett 38r ball bearing turbo, new Casserly Full Force 160/100 injectors, pedestal delete, fuel regulator return, new glow plugs, new alternator, ts 6 position chip, 450-ish rwhp.

I only last week put on the new alternator as my voltage was seemingly dropping (full time Scan Gauge on OBDII) but alas that was not it. No service lights coming on. 

I'm thinking IPS, IPR or CPS. Oil levels good, but she does use oil (sh!t ton of miles, blows white when cold) and has a small oil leak somewhere but for the most part she's always half or full. 

She starts up just fine each and every time after stall, btw..

???


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## jbwk254 (May 29, 2014)

Check the pigtails on the IPS and IPR. If you replace either do the pigtail at the same time. Also as im sure you know, oil leaks on these trucks are bad since the injectors run off of oil pressure


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## Doc Holliday (Mar 12, 2011)

Yeah, I know and I think that's the case here. Before I had the motor upgraded the intercooler O-rings went bad causing a severe oil leak as in of 18 quarts more than half would leak out on my drive way within one day. But at that time the truck never stalled. Nor did it for the first few months after cooler ring oil leak fixed and motor upgrades.

I just drove her maybe 15 miles to an interview, making sure to fill her yesterday with oil coming from about half on the stick. It appears that once the viscosity of the oil breaks down as the motor gets hotter is when the rough idling/stalls rears it's ugly head. Up to around 190 EOT no issues, smooth. 

Guess I gotta get this small oil leak fixed and/or rebuild this motor to nip the rings in the bud. 

I was thinking of either rebuilding this motor with forged rods and taking her to 600 rwhp already or simply buying a 7.3 with the forged rods and building that up to the effortless capability of 600 rwhp. 

I certainly wish this 7.3 wasn't so addicting at times..


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## Doc Holliday (Mar 12, 2011)

and thanks for your reply. :thumbsup:


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## cjm94 (Sep 25, 2011)

I agree check the icp sensor oil likes to leak through the sensor and the signal gets erratic. The new pigtail has a good length of with cut off as much of the old as you can. Oil gets soaked up the insulation and rots the wire.


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## Doc Holliday (Mar 12, 2011)

I'll check (replace) sensors first and follow up. Turns out it's definitely nothing to do with engine oil temp, has stalled out at 136 and 148, well before the motor is hot. Average warmed up running temp is 210. 

Thanks all.


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## Doc Holliday (Mar 12, 2011)

Quick update: I disconnected the icp and while she was idling rough instantly there was no stalling and no up and down idling and even with the sensor unplugged she drove just fine.

I had talked to Diesel Site a few days ago (Jennifer on the phone really knows her diesels!) and she told me I could do that for a short while as a test. That's it. :thumbsup:


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## cjm94 (Sep 25, 2011)

Doc Holliday said:


> Quick update: I disconnected the icp and while she was idling rough instantly there was no stalling and no up and down idling and even with the sensor unplugged she drove just fine. I had talked to Diesel Site a few days ago (Jennifer on the phone really knows her diesels!) and she told me I could do that for a short while as a test. That's it. :thumbsup:


It's a good idea to replace the connector too even if it's not leaking oil. Have seen many with poor pin fitment cause issues.


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## Doc Holliday (Mar 12, 2011)

will do. might be a few weeks before I get to the repair, starting new job and all but yup, I planned on it as everywhere I've searched they've all said to replace the connector too. I think the icp comes with the new connector, doesn't it? And three heat shrink wire connectors. I saw that on Youtube.


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## cjm94 (Sep 25, 2011)

Factory parts they are separate. Not sure on aftermarket though. Ford sensor and connector aren't cheap.


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## Doc Holliday (Mar 12, 2011)

Okay, I just came from my girlfriend's sister's place, her hubby is 30+ years mechanic. He put on scan tool, picked up icp first thing (still unplugged) along with a few other things but those may be contributed to their delete when I upgraded my truck. 

After looking at the wires and connector he said to just change sensor, not connector, as mine appeared to be in good shape. he did see the oil in the connecter and said to use brake cleaner and just clean it so I'll try that first, just the sensor. 

Sensor costs $163.99 at Advance Auto. I'll get to it in a few weeks as for now I'm 100% certain that's it and i'll simply leave the icp unplugged 'till then. Idling she runs choppy with rpm's not revving up and down and then she smooths out without stalling. No drop in rpm's, no stalling, just a bit choppy without foot on gas.


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## Windows on Wash (Aug 30, 2011)

Now....put some stacks on it and lets get rolling!!!









Just joking. I don't understand the fascination with taking up half of your bed for stacks.


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## jbwk254 (May 29, 2014)

Doc Holliday said:


> Okay, I just came from my girlfriend's sister's place, her hubby is 30+ years mechanic. He put on scan tool, picked up icp first thing (still unplugged) along with a few other things but those may be contributed to their delete when I upgraded my truck.
> 
> After looking at the wires and connector he said to just change sensor, not connector, as mine appeared to be in good shape. he did see the oil in the connecter and said to use brake cleaner and just clean it so I'll try that first, just the sensor.
> 
> Sensor costs $163.99 at Advance Auto. I'll get to it in a few weeks as for now I'm 100% certain that's it and i'll simply leave the icp unplugged 'till then. Idling she runs choppy with rpm's not revving up and down and then she smooths out without stalling. No drop in rpm's, no stalling, just a bit choppy without foot on gas.


Use code WD34 for $50 off orders over $125 @ advance auto


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## Doc Holliday (Mar 12, 2011)

Awesome, will do. Thanks.


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## Doc Holliday (Mar 12, 2011)

bought a new icp sensor from Advance today ($50 off is internet but in store they gave me $35 off) to no difference to speak off. 

I called a diesel outlet/shop and spoke with a tech, asked if IPR pressure was dropping and thanks to my Scan Gauge II it certainly still is. 

Next, IPR.

*ps, with icp sensor unplugged there is no restriction to injectors, or something, why she didn't stall with it unplugged. in other words just cause you unplug the icp and she doesn't stall, such is in my case, does not mean it's the icp. these baby steps sure are expensive...

duh. :whistling2:


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## cjm94 (Sep 25, 2011)

Still could be the connector. They are very common to have a poor connection causing erratic signals. With the sensor unplugged the PCM goes into a default strategy for the injection pressure which is why it smooths out.


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## Doc Holliday (Mar 12, 2011)

I'm sure, but the ipr is readily available while the connector has to be ordered. It's coming down to the wire, pun intended. 

Ipr first, then if that's not it she's going to the shop. I will let you all know what the outcome is so stay tuned...


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## Doc Holliday (Mar 12, 2011)

ipr is going to cost just over $300 from Ford. Still haven't purchased it, driving around with icp unplugged so she doesn't stall.

in the meantime, my radiator and degas (radiator overfill) bottle both blew. New upgraded all aluminum radiator plus new degas bottle plus oil change and she's back on the road, better than ever. well, once I get that ipr...:huh:


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## cjm94 (Sep 25, 2011)

Doc Holliday said:


> ipr is going to cost just over $300 from Ford. Still haven't purchased it, driving around with icp unplugged so she doesn't stall. in the meantime, my radiator and degas (radiator overfill) bottle both blew. New upgraded all aluminum radiator plus new degas bottle plus oil change and she's back on the road, better than ever. well, once I get that ipr...:huh:


 If it is running ok with the icp unplugged the ipr is working fine. It is now just getting default parameter settings from the computer. Pretty sure you will be thowing away $300.


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## Doc Holliday (Mar 12, 2011)

cjm94 said:


> If it is running ok with the icp unplugged the ipr is working fine. It is now just getting default parameter settings from the computer. Pretty sure you will be thowing away $300.


 
Okay, so? With the icp plugged in the fuel injector pressure steadily drops until truck dies. How I know is bdecuase I have a scan gauge hooked up full time through odbll port.

Why then only and again only if and when either the old icp or the new one with icp plugged in does ipr pressure drop until the point of stalling...??


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## Doc Holliday (Mar 12, 2011)

I picked up the ipr today plus paid for an upgraded and beefier steering gear box made by Redhead and paid for a remanufactured steering column. Truck going in Thursday for all repairs. 

I sure hope this ipr is it, only other thing it can be would be a weak high pressure oil pump..?? But she runs fine, tons of power with the upgrades..??

I dunno, but we'll find out.


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