P0175 code

[jerryg2112]

My check engine light came on last night on the way home from work. Forscan showed 0175 code and gave possible causes including coolant leaks. I tried to save the results but reset the codes instead. I can't remember all the different causes that it listed. Anyway there was a coolant smell and I noticed that the resservor was low an inch. Time take the plunge and redo the whole coolant system. Is there a cooling system issue that could cause the rich code? Any other usual suspects? I did notice it was running a little rough the other day on a cold start but that went away and it is running fine now. TIA

 

[04_Sport_LS]

From the internet:

"A faulty fuel injector is the most common cause of a P0175 code. As it fails, the injector will leak and push too much fuel into the engine. A leak in the fuel lines can make it appear as if the injectors are not doing their jobs."

The above description would explain your running rough issue. You may want to check/monitor your fuel pressure the next time it does it. Depending on the age/milage on your LS, it may be time to replace the fuel injectors. You could try replacing the fuel filter first. Especially if it has never been changed

Not sure where or how you are getting the idea that that particular code is related to coolant leaks. Seems you may have 2 different issues going on at the same time.

If you are smelling engine coolant and your reservoir is showing low... it's probably time for a full cooling system rebuild.

Time to Break Out Another Thousand.

 

[jerryg2112]

From the internet:

"A faulty fuel injector is the most common cause of a P0175 code. As it fails, the injector will leak and push too much fuel into the engine. A leak in the fuel lines can make it appear as if the injectors are not doing their jobs."

The above description would explain your running rough issue. You may want to check/monitor your fuel pressure the next time it does it. Depending on the age/milage on your LS, it may be time to replace the fuel injectors. You could try replacing the fuel filter first. Especially if it has never been changed

Not sure where or how you are getting the idea that that particular code is related to coolant leaks. Seems you may have 2 different issues going on at the same time.

If you are smelling engine coolant and your reservoir is showing low... it's probably time for a full cooling system rebuild.

Time to Break Out Another Thousand.

The code hasn't come back yet but last night I thought I felt surging while I was accelerating. I looked at the long term fuel trim and it was at -16 to -18. So the problem is still present and I'm sure it is only a matter of time before the code gets set again. Is there a chance fuel injector cleaner will work or should I order the count on replacing them? Is this another part that has to be Motorcraft or is there other options? I tried to find them and it seems they have been discontinued. All eight or just the faulty one if I can find it? I know it makes more sense to do them all when it is apart. 116k on motor. Fuel pressure was at 3.6v when I looked at it in park. Any tips on diagnosing this is appreciated. I used to have Chilton's through the library but they recently cancelled the subscription.

 

[04_Sport_LS]

I would check fuel pressure at the rail. It should be close to 50psi with the engine at idle.

If pressure is lower... you may have a restriction in the fuel line. With 116k on the vehicle... if you haven't changed the fuel filter, and go to crappy gas stations... the fuel filter may be causing the restriction.

Especially if you fuel up while the tanker truck is dumping a load.

 

[jerryg2112]

I not sure how to check the pressure at the rail since I don't have a schrader valve. According to the sensor I have 55 lbs. I fill at a cheap station and certainly could have issues because of it but I am not sure how I would be running rich if I have a clogged system. I will change the fuel filter to rule it out.

 

[04_Sport_LS]

You could try running a can of SeaFoam through a full tank first and see if that helps.

Beyond that... using Ford/Motorcraft parts is always the best option. Rock Auto sells rebuilt Motorcraft injectors from a company by the name of GB. I haven't heard any bad reports about them.

 

[04_Sport_LS]

There's a schrader valve on the drivers side fuel rail. I know my LS can at least hold full fuel pressure for a day, (if not longer, but it should hold indefinitely if everything is functioning properly)... because i've pushed the valve core on the fuel rail and had it spray hard.

A drop in fuel pressure caused by a leaky injector... will only cause the injector to leak more... dropping the fuel pressure more... so the effect becomes cumulative. That will eventually dilute the oil... risking premature engine wear.

 

[jerryg2112]

There's a schrader valve on the drivers side fuel rail. I know my LS can at least hold full fuel pressure for a day, (if not longer, but it should hold indefinitely if everything is functioning properly)... because i've pushed the valve core on the fuel rail and had it spray hard.

I've looked the fuel rails over many times and cannot find one. Even mentioned it in a previous post from 2019.
Help! Can't find problem of not running
Apparently not all of the LS's came with schrader valves.

 

[joegr]

There's a schrader valve on the drivers side fuel rail. ...

Nope, not on all years. One of mine had one, and the other did not.

 

[04_Sport_LS]

Interesting. I guess that's what I get for assuming.

 

[jerryg2112]

Update. The code hasn't come back but my long term fuel trims are still -14 and -18 ish. Sometimes I think both banks are the same and sometimes I think bank 2 is 4% worse. On my second tank of gas with Seafoam and haven't seen a change. Just replaced the fuel filter today and checked the fuel pressure while I had it apart. I have attached some photos for anyone who is interested. It still infuriates me that there is no Schrader valve. Fuel pressure was about 5 lbs less than the pressure Forscan is showing. I think that rules out the fps. Next step is pulling plugs I guess. I would expect the banks to be a lot different if I had a leaking injector. I suppose I could have more than one.

The piece is from a fuel pressure tester kit that I loaned from Oreilly's. The plastic hose is 3/8 od and is rigid enough to withstand vacuum which is why I bought it in the first place. I put some zip ties on in case the pressure wanted to push out the lines.