Error Code p0191

[Qewlan]

Hello everyone!

First, sorry for bad spelling (android really likes changing words for me).

Next, I hope someone here can help a swede out with his Avensis.

When driving the car goes into "secure mode" and I cant get over 2000 RPM (which can be bad when you are on the highway). The error code i get is P0191. So far I have changed the fuel pump (because I thought it might be the filter that is clogged up). There is very little information to get about these models, and yes I have been reading threads here regarding the same problem (if there are any problems with my Volvo there so much guides and info, but that might be because I am Swedish).

Does someone have anything that can help me out with this matter since it is making me crazy.

Edit

Its a 2005 Avensis Station Wagon T25, 2,0L Petrol Engine(AZT250), 147HP from 2003.

[mrfixer]

P0191 indicates an unexpected signal from the fuel rail pressure sensor.  This is a sensor which is installed in the fuel rail on the engine.

The sensor receives a 5V power supply voltage from the engine control unit (ECU). It also has a ground connection.  There is an output signal to the ECU. An output of 0.5V = 0psi pressure and 4.5V = about 2000psi pressure.

You need the Toyota wiring diagram. Check the 5V supply, the ground and the output signal. Check the wires and connections. If the wiring is OK it is most likely that the sensor has failed. Replace it.

[Qewlan]

Oh, thank you for a quick response!

You dont happen to know how it looks like? So I can see what I am looking for and order one in advance (IF its now that expensive).

[mrfixer]

 

14 hours ago, Qewlan said:

Oh, thank you for a quick response!

You dont happen to know how it looks like? So I can see what I am looking for and order one in advance (IF its now that expensive).

Something like this....https://rover.ebay.com/rover/0/0/0?mpre=https%3A%2F%2Fwww.ebay.co.uk%2Fp%2F650087181

[Ardewerde]

Hi folks, new here i had same problem and solution was to replace 1 O-ring in high pressure pump. just remove 3 screws on top and pull the center part out.

-Ari-

[Jarkko]

I also changed the O-ring sealant and my avensis T25 turned into a different car. Smoke from the exhaust decreased a lot and P0191 vanished from failure list.

Thanks ARI for your reply. Seal cost only 0,30€ so it was cheap and easy fix.

[Geir H]

Jarkko and Ari, interesting about the O-ring. Where did you buy the o-ring and what is the size?

I have an intermitent problem, and som smoke from the exhaust.

Thanks!

[Jarkko]

Hey Geir

I bought an o-ring seal from a local auto parts store. That O-ring seal is just an ordinary seal and is sure to be found in almost every car parts store. I will attach few pictures. In the first picture the mere seal and in the second image I displaced the pump completely (which is therefore not necessary, the seal is on the top of the part) where you can see the seal.

[Janne]

My avensis had the same symptons and error code. In my case the problem was smaller o-ring seal (approx 12mm) in the same part. Thanks for the tip!

[Ardewerde]

On 1/9/2021 at 3:36 PM, Janne said:

My avensis had the same symptons and error code. In my case the problem was smaller o-ring seal (approx 12mm) in the same part. Thanks for the tip!

Nice, mine was Also The inner Ring about 12*1,5 or something, actually smaller Ring is possibly to chance without remove whole pump. Just remowe 3 screws from top and you can remowe The top Part.

I get this tip from Finnish Toyota Forum.

 

 

 

[ulflun]

I seem to have the same symptoms. 2.0 engine. Some startup it gets rough idle and then goes into limp mode. Restart and it works as normal. Getting code P0191. Do you guys have any further instructions for this fault? Pictures? 

 

Is it this pump?

https://youtu.be/TV3IUyAedjE

[ulflun]

Did you guys disconnect the Battery and/or empty the fuel lines (disconnect fuel pump and run the engine until it dies?) Is it possible to remove the upper part without getting fuel everywhere? I guess it is this three screws (picture)? 

If it's a common problem I might be able to make an short video changing the o-ring while I'm on it.
 

[ulflun]

On 1/22/2021 at 4:09 PM, Ardewerde said:

Nice, mine was Also The inner Ring about 12*1,5 or something, actually smaller Ring is possibly to chance without remove whole pump. Just remowe 3 screws from top and you can remowe The top Part.

I get this tip from Finnish Toyota Forum.

 

 

 

Is it the screws in my picture above? Did you need to discharge the fuel system pressure before removing the top part?

[Jarkko]

There is no need to disconnect Battery or empty any fuel lines. Just use a rag when opening.

[ulflun]

Hello! Is this the smaller o ring you refer to? Or is it in the other part? The small o ring has edges but I guess i can replace it with a ordinary one?

 

 

 

[ulflun]

Or is it this one? Seems like it's another o-ring down there, but I can't really tell. A little hard to see from the angle, and also hard to reach without removing the whole pump.

[Ardewerde]

1 hour ago, ulflun said:

Hello! Is this the smaller o ring you refer to? Or is it in the other part? The small o ring has edges but I guess i can replace it with a ordinary one?

 

 

 

I  changed only that one, youl see If IT Works after that.

[ulflun]

1 hour ago, Ardewerde said:

I  changed only that one, youl see If IT Works after that

Thanks, I'll try. Did your old o ring look obvious damaged/old? Mine did not look to bad, but I guess it is hard to tell.

[BALIKBAYAN]

I have the same problem with my Avensis at the moment, P0191 and occasional P0192 wich is not mentioned in the workshopmanual. The car is almost impossible to drive right now. I noticed last night that it was idling at an unusual high rpm too. I had about 1100 rpm when the engine was idling. When I connected my obd-reader I got the normal rpm when idling again.

When I checked the valve clearance a few years ago with a feelerblade I had to disassemble the fuelsystem. It was not that difficult but there were lot of parts that had to be renewed when assembling the fuelsystem again.

I will pass the local Mr T and buy the gaskets I will need tomorrow.

I noticed one thing with this thread. Everyone who has had written in this thread is NonUK except MrFixer who answered the first post. Is it something with the petrol we have here in Scandinavia that makes this to the high pressure fuel pump?

I refueled the car yesterday. I was surprised that suddenly the 95 octane was e10 fuel. A week ago when I refueled the car  both 95 and 98 octane was e5 fuel.

 

 

[BALIKBAYAN]

I changed a broken o-ring to the sensor and I went for a drive. The problem seems to be solved.

Thanx for this great forum.

[ulflun]

19 minutes ago, BALIKBAYAN said:

I changed a broken o-ring to the sensor and I went for a drive. The problem seems to be solved.

Thanx for this great forum.

Great! I did not have the same luck thought. Still same issue here. It always happen when I got half tank or less, so the pressure seem to fail. I guess the fuel pump might be the issue.

[ulflun]

On 7/4/2021 at 1:07 PM, BALIKBAYAN said:

I have the same problem with my Avensis at the moment, P0191 and occasional P0192 wich is not mentioned in the workshopmanual. The car is almost impossible to drive right now. I noticed last night that it was idling at an unusual high rpm too. I had about 1100 rpm when the engine was idling. When I connected my obd-reader I got the normal rpm when idling again.

When I checked the valve clearance a few years ago with a feelerblade I had to disassemble the fuelsystem. It was not that difficult but there were lot of parts that had to be renewed when assembling the fuelsystem again.

I will pass the local Mr T and buy the gaskets I will need tomorrow.

I noticed one thing with this thread. Everyone who has had written in this thread is NonUK except MrFixer who answered the first post. Is it something with the petrol we have here in Scandinavia that makes this to the high pressure fuel pump?

I refueled the car yesterday. I was surprised that suddenly the 95 octane was e10 fuel. A week ago when I refueled the car  both 95 and 98 octane was e5 fuel.

 

 

You are probably on to something. According to Bil Sweden the new E10 fuel can not (should not) be used with following Toyotas:

Toyota

New cars: E10 can be used in all petrol models manufactured after 1.1.98 with the following exception:

* Avensis 2.0 VVT-i (1AZ-FSE) manufactured July 2000 - October 2008.

* Avensis 2.4 VVT-i (2AZ-FSE) manufactured June 2003 - October 2008.

[ulflun]

For further reference:

In my case a new fuel pump (the large one, located in the fuel tank) solved the issue. 

Had error code P0191 and P0192.

[MichaelNL]

Hi all, just wanted to say thanks for the information here. I was presented with a p0191 error code too. In my case it was the same o-ring. 
 

I’m replying to say thanks and give some additional info for future searchers.

car: Toyota Avensis 

engine: 2.0 VVT-I

O-ring size: 11x2mm

issues:

- at intervals no power. No gas response. Happens when driving away from traffic lights and even when simply cruising. Suddenly the car jerks and all power is gone.

the fix: remove the top part of the high pressure fuel pump (3x inbus 5mm). 

Replace the small o-ring. That’s it.