OBD code P0190 - Fuel Rail Pressure Sensor Circuit Malfunction

[icarusi@hotmail]

Got the OBD code P0190 - Fuel Rail Pressure Sensor Circuit Malfunction today. 2009 petrol 1.4 TSI Octavia. It starts and runs ok, but a couple of years ago it started stalling if I did some stop/start motoring after the engine was up to temperature. Normally I don't do stop/start stuff, mainly 5-15 miles park an hour or 2 and return, so don't know when the problem actually started. I did a start/stop today and the intended parking spot was full, so I drove on and it stalled on a straight and level section. I wasn't expecting it, but there was no 'kangaroo petrol' etc. just the power disappeared. Because I was still rolling I tried to bump start it, but no joy so I rolled it to the kerb. After a couple of minutes I restarted, joined the traffic but it wasn't revving high, 4k revs max, and I was heeling and toeing etc. trying to keep the revs from falling to idle until I got to the next parking spot. I left it for an hour or 2 and when I started it I got a steady yellow Engine Management Light which didn't go, even after a restart on my drive. The revs seemed ok by then.

 

I plugged in my OBD reader and got a P0910 code. Previously when it was stalling I was getting no codes and no warning light.

 

 

I found this for P0190 code:-

 

What causes the P0190 code?

• Bad fuel pump
• Bad fuel pump driver/relay
• Bad fuel rail pressure sensor
• Clogged fuel filter
• Vacuum leaks
• Low or no fuel
• Wiring that is exposed, damaged, melted, or corroded
• Connectors that are exposed, damaged, melted, or corroded

 

 

And this for the EML:-

 

1. Oxygen Sensor malfunction (emissions issue)

One of the many sensors monitored by the ECU, the oxygen sensor measures the amount of oxygen that goes unburned in the car’s exhaust system. A failed O2 sensor will cause more fuel to be burned than is necessary. This, in turn, will dramatically lower the car’s fuel efficiency. You can still drive your car with a malfunctioning oxygen sensor, but your MPG figures will suffer until the issue is fixed.

2. Loose or faulty petrol filler cap

An illuminated EML doesn’t always highlight a major problem, sometimes it can be as simple as your petrol filler cap being loose. It’s easier than you think to fill the car up at the petrol station and drive away having not properly tightened the filler cap. An improperly fitted cap can play havoc with your car’s fuel economy and emissions levels, as it allows fuel hydrocarbons to leak out and pressure to be lost.

If your check engine light comes on, it may be worth quickly pulling over and making sure your filler cap is properly tightened. At the same time you can have a look for any cracks or damage to the cap. A new filler cap is inexpensive and may fix your problems.

3. Catalytic Converter issues

Your car’s catalytic converter turns harmful carbon monoxide into carbon dioxide. If you keep your car regularly serviced, it shouldn’t fail completely. More often than not, issues with the catalytic converter are symptoms of another part failing, such as the oxygen sensor or EGR valve. However, the catalytic converter itself can become clogged if you only ever drive short journeys.

To help it remain clean and efficient, it may be worthwhile to occasionally take your car on the motorway. If it does fail, your emissions levels will increase, causing the engine management light to illuminate.

4. Mass Airflow Sensor malfunction

The mass airflow sensor’s job is to tell your car’s ECU how much fuel to add into the engine’s combustion chamber to match the amount of air flowing into the engine. These levels ensure that the car runs as efficiently as possible.

A potential failure of the sensor will cause your car’s fuel economy to increase and your engine to occasionally stall, as incorrect levels of fuel are being delivered into the combustion chamber. As the mass airflow sensor sits behind the air filter in the car’s engine bay, faulty readings or a total failure of the sensor are often caused by issues with the air filter itself.

You should have your air filter replaced once every twelve months to ensure that it is fitted correctly and working properly.

5. Faulty spark plugs/wires/ignition system

Your spark plugs ignite the fuel in your engine’s combustion chamber. If a spark plug or its wiring fails, you will notice a decrease in your engine’s power, as well as it stalling from time to time. It will also cause your engine management light to become illuminated on the dashboard. Your spark plugs should be changed regularly in line with your manufacturer’s schedule.

6. Malfunctioning DPF

The Diesel Particulate Filter is a part that’s fitted to the exhaust system of diesel cars. As exhaust gases pass through the exhaust system, the DPF removes any harmful particles. These particles build up over time to form a sooty deposit that can start to clog up, causing the DPF to underperform.

When this happens, the filter sends a signal to the ECU. In turn the ECU tells the car’s engine to start the DPF regeneration process, whereby extra fuel is burned by the car in order to increase the temperature in the DPF and burn all the deposits, cleaning the DPF. If the DPF fails, it doesn’t send those signals to the ECU causing power to be reduced and emissions levels to increase, resulting in the check engine light coming on.

7. Vacuum hose leak

Your car’s engine contains numerous vacuum hoses that help to control a number of functions, one being the lowering of harmful emissions through the car’s exhaust system. Due to the fact that these hoses are constantly exposed to extreme temperatures, they can easily become cracked, causing the part to fail. In turn, this can cause a specific sensor to inform the ECU of a problem, resulting in the engine management warning light being lit up.

8. EGR valve failure

The Exhaust Gas Recirculation valve controls the amount of nitrogen oxide in the car’s engine, helping to improve its efficiency. It does this by redirecting a portion of the exhaust gases back through the engine’s cylinders, where they are used again in the combustion process. The EGR valve can become stuck open or closed due to a build-up of particles, which will cause a fault, resulting in the engine management light being illuminated on the dash.

9. Fuel Injector problems

The fuel injector moderates the amount of fuel that is delivered into your car engine’s combustion chamber. Occasionally they can become clogged, which causes them to underperform or fail entirely. They also rely on the information received by the ECU from other sensors around the car, so failures in other elements can have an effect. As soon as the fuel injector stops working efficiently, the ECU will illuminate the engine management light.

10. Fuel Pump problems

A failing of the fuel pump will cause incorrect amounts of fuel to be delivered, causing the ECU to report a fault and the check engine light to become illuminated. Once the fuel pump does start to fail, it is likely that total failure will follow shortly after. With that in mind, although you can continue to drive your car, you should have the car checked at your local garage as soon as possible

 

I was considering replacing the fuel filter but I now think it's one of the flow sensors going out of spec when it's hot ? Any ideas? I'm thinking the mass airflow sensor is a possible. 

I

Edited 8 March, 2018 by icarusi@hotmail

[icarusi@hotmail]

Apparently the TSI doesn't have a MAS.

[icarusi@hotmail]

I found the MAP and it's relatively easy to access. Got some quotes for the part locally and they're actually less than online, just an order-in component. I'm going to check the existing  part (connections) and readings before I swap it out then at least I'll have a comparison.

Edited 8 March, 2018 by icarusi@hotmail

[icarusi@hotmail]

Found the IAT sensor and the MAP sensor are the same 038 906 051B part, so I only need one to check both (assuming both aren't faulty). I ran the car today and couldn't replicate the fault, so I reset the code and it hasn't recurred. I made a note of the idle rev ranges whilst it was running ok today, so I can see if it goes any lower in different situations in the future. Lowest was just over 300 and often  not less than1000 rpm. I can also replicate the run when the fault occurred when I have more time. I'll also check the outside air temp. IIRC the stalls have always been in twilight/dark but may have been coincidental.

Edited 13 March, 2018 by icarusi@hotmail

[icarusi@hotmail]

Never sorted this, but the car was going ok on short trips, and I could never get the same fault and code to reappear for a Vag-com scan at a local repairers.

 

Got a 'P0192 – Fuel rail pressure (FRP) sensor -low input' code today into a similar longer journey, but this time it didn't self-correct and I needed a recovery. I'll check again tomorrow, but currently it's not driveable. No limp-home mode, which seemed to be what should have happened if it was the FRPS at fault, after a reset. The same code came up and same, hunting-to-stalling on idle, but high revs + no power if you used the accellerator. The recovery guy was sure it was the FRPS until he did the reset and the same fault code returned. I'm not sure the FRPS is completely innocent yet.

 

Would a VCDS scan give better detail of the components involved in a P0192 and P0190 code fault, or just the usual suspects mentioned with these codes?

Edited 25 December, 2018 by icarusi@hotmail

[icarusi@hotmail]

Seems to be very similar detail on VCDS, just different code numbers, unless someone here knows more?

 

http://wiki.ross-tech.com/wiki/index.php/16574/P0190

 

http://wiki.ross-tech.com/wiki/index.php/16576/P0192

[Papfox]

Has the battery in your car been replaced since it was new? As has been discussed in threads about other strange faults, the Octavia II is prone to starting OK but exhibiting strange electrical symptoms when the battery starts to go soft. If your battery is original, it's over the age where people are saying they can start to cause issues. This may well be nothing to do with the problem your car has but it's over the age I would think about replacing a battery for my own peace of mind.

Edited 26 December, 2018 by Papfox

[icarusi@hotmail]

9 hours ago, Papfox said:

Has the battery in your car been replaced since it was new? As has been discussed in threads about other strange faults, the Octavia II is prone to starting OK but exhibiting strange electrical symptoms when the battery starts to go soft. If your battery is original, it's over the age where people are saying they can start to cause issues. This may well be nothing to do with the problem your car has but it's over the age I would think about replacing a battery for my own peace of mind.

I thought that too, so I replaced it and drive with a multimeter connected via the accessory socket so I could check on the voltage levels at idle speeds and nothing showed suspiciously, but the fault usually occurred when slowing but only after a restart with the engine still warm after reasonable length journey. if it was a manual choke, it was suspiciously similar to too much/little choke.

[icarusi@hotmail]

Wouldn't you know it! I went out today expecting the car to be acting the same as when it faulted, inc. stalling as I drove it into my drive on Xmas eve. It fired up ok, no sign of hunting, stalling, lumpy running, so I backed it out of the drive and still no problems. Didn't run it further so I don't get stranded before my local garage has a look.

 

I'm going to leave it 'til after new year, then book it in for a VSCD scan there, with the proviso they'll tow me in if it acts up en route. The distance there is just enough to reach full temperature, so I may be able to get it to act up at, or near the garage, otherwise I'll do the 16.5 miles of the last 2 times it's happened, but circuit locally to be in reach of the garage.

 

I did take the plastic engine cover off, just to check there's nothing obvious being hidden. Good job I did, as the bottom LH screw was rusted in. It nearly sheared off a torx key, and I had to use a 3/8" drive version to break the rust grip, not something I'd have been able to do with the tool set I carry in the car.

 

Despite appearances the sensors under the cover aren't to do with the fuel/air system, just the G40 Hall sensor/sender and 'Camshaft adjustment valve 1 -N205' according to the manual.

 

Edited 27 December, 2018 by icarusi@hotmail

[icarusi@hotmail]

The car eventually went into fault mode and stayed that way. I swapped out the fuel rail pressure sensor, which I'd bought but kept back until the fault showed, but no joy. I got a boost pressure sensor but didn't fit it until I'd checked the fuel and low pressure side. Usually when I turned the ignition key, I heard clicking from the back and assumed it was the pump operating, so I disconnected the low pressure feed to the HP pump and there was fuel there, so I connected a bottle to collect some more fuel, but when I switched on the ignition no fuel emerged. I checked in the cab and no clicking sound now. So the problem was further back.

 

I got a replacement fuel filter, disconnected all the lines, collected what fuel was in the line forward of the filter and what was in the filter. Nothing conclusive in what I collected and the line a filter seemed ok. I put some fuel back into the LP line from the HP pump connection end and forced it through with my tyre inflator and the fuel went through ok, no obvious muck blocking it, nor anything obvious in the fuel filter

 

Next back was the pump. I hadn't checked it before because it always seemed to be working ok, but as soon as I checked there, the electrical box serving it had a spot of oil on a corner. When I pulled it up, the corner was also partly melted. Not good! Anyhow this is the 'fuel pump controller relay', so did a quick search for associated problems. Very little here in the UK but a lot from the USA inc. a big recall. The symptoms are wide and varied but can include low (or high) fuel rail pressure.

 

I found one available not too far away but the firm has recently moved further so I couldn't collect, so ordered it yesterday and fortunately it arrived today. I decided to check the pump by connecting power directly to the exposed pump connector pins, as per the Skoda workshop manual. I'd connected a bottle to the fuel filter line which I'd left disconnected and the pump delivered into it ok. So I now have a clean sample of the tank fuel.

 

I connected up the new fuel filter, then the replacement 'fuel pump controller relay' and switched on the ignition but couldn't hear any clicking or other noise, but gave it a go anyway. No joy!

 

I checked the manual for fuses and No27 looked possible. No27 was blown, but I don't have any 15A fuses, but I moved one from another slot and tried again. Still no joy, but I could hear the pump motor working this time, but no clicking. I switched ignition off and on, and  the pump motor ran longer. I tried starting again, and this time it fired up. I kept it running until it was up to temperature, then switched off an did an OBD2 scan. The 0192  and 1 N/A are still there but the 2 'pendings' are gone.

 

I don't have time to take it for a spin til Monday, but fingers crossed the FPCR is the culprit of the intermittent stalling. FPCR VAG No is  1K0906093G and the one replaced is 1K0906093F (both VW KUHNKE stamped). I'll check what my local VAG spares place is using next week.

 

Edited 13 September, 2019 by icarusi@hotmail