Idle control system P0505:00

[waverider57]

Having trouble with my son’s 2016 Fiesta ST idling rough. Replaced bad low pressure pump sensor (P0018D) by the firewall, and the main battery, but we have a new code pointing to the idle control system, P0505:00, kinda generic, does anyone know if this is the IAC Valve, or where I should look? The car barely runs at all, so it’s hard to make it through a full scan without a restart. This code was picked up with no stalling, so it’s as good as I could get. I’m also getting a coolant temp sensor out of self test range, and a code for the annoying HVAC clicker. Thanks in advance!
Dave

 

[Intuit]

Any alterations from stock? MAP is less susceptible to vac leak but no invulnerable. I suspect if you get enough drive cycles without reaching operating temp, it may trigger the particular code? Have to read the descriptions in the manual.

 

[waverider57]

No modifications, but there’s a lot of oil in the intake from the top engine breather throughout the charge pipe. Milky colored, it’s very humid here in NE FL.

 

[waverider57]

I can get it to idle high by pulling the vacuum line from the front of the intake manifold at the throttle body, I believe that’s the fuel purge valve inline about 8” back from the end connector. That’s when the neighborhood gets a free mosquito treatment from the grayish smoke pouring out of the exhaust pipe. Some does seem to be coming from somewhere else on the engine, I’ll have to get another look at it later today.

 

[Intuit]

Mileage? Pull and read the spark plugs.

 

[waverider57]

61k miles. Plugs were originals, installed new, nothing out of the ordinary, the car suddenly started running poorly and stalled, so no plug pattern could be seen other than normal up to the moment the engine stopped. Wet with oil was the only thing I could see wrong with them, but wasn’t sure if it was more fuel than oil. Very thin viscosity.
Today, I pulled the breather hose off of the side of the charge pipe, and smoke spewed out of the hose I removed, but the engine picked up and ran smoothly until it appeared it got too much air, and started to stumble.

 

[waverider57]

I’m aware that we have a GDI and a ford turbocharger system here, but could this be oil from a massive oil leak in the turbo? I’ve never seen that much smoke pour out of an engine breather hose in my 50 years of wrenching cars and motorcycles.

 

[Intuit]

Lots of oil in the intake... certainly could be a source. Was the oil grossly overfilled at any point that it would be sucked up via PCV system?

 

[waverider57]

My son had an oil change done by a quick lube place just prior to this. There’s a heavy gasoline smell in the oil already, so I thought it might be a bad GDI injector or two, and it was cutting fuel at -25 short term when it did run, with everything connected up. Long term fuel was at 0 since this just started.

 

[waverider57]

Compression tests show from 195-210, all four holes, it was a sudden onset that caused him to have to pull over immediately. Had the car towed to my house a week ago the morning after the incident occurred. He said he wasn’t dogging it when it happened, and the engine hasn’t been able to run above 400 rpm, and it has caused low voltage PCM readings and screwups in the can bus. I first changed the five year old battery and the original plugs, and a scan showed the low pressure fuel pump sensor was bad, the one on the fuel line way back on the firewall. That’s all the parts I threw at it so far, I suspect the turbo seals on the exhaust side are shot, because SOMETHING is burning that oil and sending it back into the engine. The intake pipes are coated in a yellow tinged oily substance that is probably oil, fuel, and moisture. I may have troubleshot this as far as it goes already. If I’m missing something simple, I’d love to hear it!

 

[waverider57]

Ok, I removed the charge pipe from the intake branch to the drivers side intercooler branch, and started the engine. Ran fine, still some smoke coming from the charge pipe, but now that I’m not re-burning it, the smoke has diminished significantly. Im going to start pulling the charge pipes near the turbo to get a better look. Is there a factory attempt at a catch can somewhere? My T100 is supercharged, and I had to check/dump it weekly with 14 psi on my daily driver. It can’t be vented to atmosphere, you’d lose boost, so how did Ford try to take the maintenance out of a turbocharged engine for the masses who don’t check their own cars?

 

[Capri to ST]

Is there a factory attempt at a catch can somewhere?

There is an air / oil separator, a vent hose goes to some kind of built-in oil separator.
I've picked that up from reading on here, but I can't give you any more specifics about how it works.

 

[Intuit]

Sounds like it was grossly overfilled. Yes there is a separator for PCV but if it's being fed pure oil...

As long as there's a crap ton of oil in the intake, it's normal for it to smoke.

Some fuel smell in the oil is normal but if it's missing, it's going to be even worse than what is normal.

.

 

[waverider57]

At the moment, the intake hose is loose, and the engine is running without any of the turbo output coming in. The MAF sensor by the airbox is not inline, so after a while, the computer doesn’t know what to do with the A/F, so it doesn’t idle smoothly, but it idles much better, and there’s no smoke in the exhaust tailpipe. The smoky vapors are pouring out of the turbo outlet, and puddles of oil were part of the removal process of the charge pipes from the intercooler to the turbocharger outlet. Since the intake manifold is coated with oil as well, it began to run through the intakes and into the combustion chambers, and a little smoke from this was visible from the exhaust pipe.

 

[waverider57]

Sounds like it was grossly overfilled. Yes there is a separator for PCV but if it's being fed pure oil...

As long as there's a crap ton of oil in the intake, it's normal for it to smoke.

Some fuel smell in the oil is normal but if it's missing, it's going to be even worse than what is normal.

.

I believe, now that the turbo is out of the car, that overfilling the engine oil was the original reason for the engine smoking and running badly. Now I’m wondering whether the turbo is still in good shape, but testing it is only an option if I re-install the turbo and run it to see if the oil change was the reason. Of course, I’ll do a visual inspection of the key components before I sign off on a re-installation. Any thoughts? I don’t see anything obviously wrong with the moving parts so far.
Thanks to everyone who has helped me out so far, I really appreciate your input and advice.

 

[waverider57]

Just for my own peace of mind, I’m going to pull the intake manifold again, and look at the PCV box bolted to the block behind it. I’m sure the PCV valve ingested most of that excess oil. At minimum, I’ll try to clean it, but if it’s sketchy, I’ll replace the box. I’m hoping that it will allow me to remove the PCV valve itself from the assembly. If anyone has tried and has experience with this, I’d love to hear it! Thanks again!

 

[waverider57]

Well, I finally found time to inspect the turbocharger, and now it’s obvious why the engine ran so badly. The exhaust turbine was flopping around inside the housing, the shaft is broken, and the intake side shaft is still in the bearing, but not the exhaust side of the shaft. I was running straight exhaust gases into the charge pipe through the turbocharger. That’s not going to run right, for sure! I’m glad I found a definitive answer to this problem, though I am worried that some of the metal debris from the turbo got into the intercooler and along the charge pipes going into the engine. Luckily, these turbos are so small that there isn’t that much metal to sling around, but a few sparkles in the oil is all it takes to bring it to its knees. Any ideas of a good way to “wash out” my intercooler?

 

[Intuit]

Removed from the vehicle, should be able to clean it out with a water hose and a little soap? Should be able to dry it out by attaching a shop vac to one end?

 

[waverider57]

Yeah, a leaf blower would work too!😵‍💫

 

[TyphoonFiST]

Stock turbos are cheap slightly used around here* If your on facebook there are a couple of groups to submit a wanted thread for the Turbo.