Got a P0190 code

TooManyToys

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So the other day I started the LS and was going to the store. Never made it as the engine was running rough, set a CEL and could hear a strange whine. Had to turn around to get back to the house, but left it running so I could try to hear where the whine was coming from. It appeared to be under the rear seats (fuel tank) and I noticed black smoke coming from the exhaust, running very rich.

Plugged in my ECM and turned on my iPhone with Forscan and read a P0190 code, no others. P0190 is fuel pressure sensor out of range. Fuel pressure is something I don't normally look at on long drives with the iPhone, and since this was a store trip, I never bothered to connect up Forscan.

A few weeks ago I felt the engine occasionally running a little rough, and I had the Forscan up and running and saw a few misfires. It's been a little rough on initial startup too. The Motorcraft COP's of 37k may have gotten cooked during the winter when I had an overheat. But I've also seen a misfire count when regular gas had been filled, so on the possibility the last station got a mis-drop and I got regular rather then mid-grade, at 1/2 of a tank I filled with super. It seemed to run well without the count so not another thought.

I plugged in my fuel pressure guage, cleared the code and restarted the motor. No misfire and pressure was reasonable. No CEL either. I set up to read fuel pressure on the iPhone and took a ride around the block. Nothing significant with pressure but caught 2 on the misfire count. Checked wiring, etc and all good.

The LS had a fuel filter change within a reasonable time, but it's a cheap part to throw in, so it got replaced. I had to do a 40 mile drive and on the trip down the LS ran well, a couple of mi-fires but without the Forscan, you wouldn't know. The return trip logged a few more.

Next run was a 15 mile trip to my wife business to do some maintenance and the run down was uneventful, again 3-4 mis-fire count. Coming back 15 minutes later after a heat soak, not so good with a few situations of rough running.

This is an image of maybe 4 miles in, pretty steady on pressure.

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Still didn't feel anything, but could see a weird event along with another mis-fire count.

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Then things got really shaky, pressure wise and mis-fire.

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And a few seconds later this is the trailing graph.

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In the driveway, this ....

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Pretty calm at low volume draw at idle.

So the quandary:

Is this a fuel pump issue.
Is this a fuel sensor issue (I don't think so).
Is this a coil(s) backing out the fuel pressure sensor by the right bank.
Is this a fuel level sensor issue and I'm less then the 1/4 tank I think I have.

Continue next post .....
 
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Checked out a Motorcraft fuel pressure sensor, the '03's are out of stock until sometime in October. A fuel pump assembly and jet pump combined are $1500, not a less see if this works parts throw. I may try to cobble up an extension for my fuel pressure gauge, but as I said, not sure the sensor is bad.

Looked around for a used fuel pump and there are a lot out there, eBay and salvage. I could pop one in for less then $75 and see if there is any difference. RockAuto and Advance have a more reasonable price for aftermarket pumps, but not all that comfortable with them.

Can also drop in a few new coils to hunt for a bad one rather then getting hit at the dealer for diagnostics.

So today I thought I'd open the tank to see if I had a fuel level sensor issue, socks going bad, something visible before I start spending bucks. So with the jet pump side open I thought I found my problem.

It's empty down there.

IMG_2773.JPG


But since I've not had to deal with this before, I'm not sure how this works. Are both sides of the tank kept balance in volume or something else.

So time to open the true pump side. It's hard to see with this image, but there's a decent amount of fuel in there.

IMG_2801.JPG



I'm guessing that the drivers side gets transferred over to the pass side, unless there is a fault here.

So has anyone gone down this path before with this issue.
 
Which cylinders have the misfires?
Did you check the wiring to the fuel pressure sensor?
What about the vacuum hose to the fuel pressure sensor (part of the bundle to the EGR valve)? This vacuum hose/tube set is well known for cracking.
 
All the vac lines were changed 37k ago along with all the cooling plumbing and COPs. (100k preventative maintenance schedule). But I did check the vac lines and wiring, including while the engine was running.

I'm not seeing any indication of which cylinders are misfiring. Maybe I've missed that in Forscan (typically use it with my diesel). Will AE show the cylinders without a code?
 
I don't know about Forscan, but my scan tool shows the cylinder(s) misfiring under the results tab.
 
I'll go through the Forscan to see if I missed something. I haven't used my AE for a couple of years but I'll check with that, too. Thanks for mentioning it. I think I'm going to recheck wiring and vac lines again just to be sure.
 
Started it up today with AE installed, but no codes in memory, and running KOER tests showed 1 count of a misfire of Cyl 3.

Pulled AE since the laptop battery doesn't have a long capacity. Also reinspected the wiring and vac lines, all good engine off and engine on. Pulled the right bank coil cover to see if they was a water pool in there, but it was dry. I didn't put the cover back on and didn't have time to pull the left cover.

So now some changes from the other day which are the electrical connection to the pass pump has been removed and reinstalled, $20 of gas added (low fuel went on) and the coil cover on the right bank is off. Damn thing ran fine today with no mis-fires. Fuel pressure can show a few pounds squirrelly, but I have no history of watching that readout.

On acceleration ....

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20 mph by home .....

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Maybe the connection, maybe the added fuel, maybe the coil cover off (less heat) .......
 

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