Turbo Recon.

[Bodgit-fixit-run]

Ok so got the dreaded. P1251 error code again yesterday. Similar scenario to last year in that it was peeing with rain only difference was I was towing this time. Lost power and tripped into limp mode. I reset the ecm clearing the fault code and it's running fine again at the moment.

Research says it's probably a turbo problem. Overboost or sommat. Now done just over 80K miles so wondering if a good clean up is all that is required. Seems that this may be due to carbon build up if I have understood it right causing the wastegate to stick.

Does anyone have an explosion drawing of the turbo? and what else do I look for? I'm about to do the 80K service anyway. I like to do my own stuff as it saves a lot of labour costs.

Thanks in anticipation.

Malc.

[Bodgit-fixit-run]

Ok so got the dreaded. P1251 error code again yesterday. Similar scenario to last year in that it was peeing with rain only difference was I was towing this time. Lost power and tripped into limp mode. I reset the ecm clearing the fault code and it's running fine again at the moment.

Research says it's probably a turbo problem. Overboost or sommat. Now done just over 80K miles so wondering if a good clean up is all that is required. Seems that this may be due to carbon build up if I have understood it right causing the wastegate to stick.

Does anyone have an explosion drawing of the turbo? and what else do I look for? I'm about to do the 80K service anyway. I like to do my own stuff as it saves a lot of labour costs.

Thanks in anticipation.

Malc.

Just thought I would have another go with this post. Fault dissapeared for quite a while and has now returned. A bit like me really sadly not beena round for quite a while following a bereavement but back now. Any thoughts would be most welcome.

[anchorman]

Heyup stranger!

Good to hear from you and sorry to hear about your misfortune.

I will have a trawl in the manual and see what I've got. The fact that it went away for such a long time makes me think it might not be anything fundamental so keep your fingers crossed.

[Bodgit-fixit-run]

Heyup stranger!

Good to hear from you and sorry to hear about your misfortune.

I will have a trawl in the manual and see what I've got. The fact that it went away for such a long time makes me think it might not be anything fundamental so keep your fingers crossed.

Thanks for that Anchorman.

just to update you.

The fault is mainly comming up when towing a caravan. Leicester to Southport at the weekend. Three times each way all, on the motorway in 5th gear. Clear the fault and it runs ok for a while.

Just a bit confuse regarding the wastegate stuff. I noticed in another thread you said there isn't one but valves instead. A specialist I spoke to on the phone said something about there being a luver type assembly.

Bodgit.

[anchorman]

Heyup stranger!

Good to hear from you and sorry to hear about your misfortune.

I will have a trawl in the manual and see what I've got. The fact that it went away for such a long time makes me think it might not be anything fundamental so keep your fingers crossed.

Thanks for that Anchorman.

just to update you.

The fault is mainly comming up when towing a caravan. Leicester to Southport at the weekend. Three times each way all, on the motorway in 5th gear. Clear the fault and it runs ok for a while.

Just a bit confuse regarding the wastegate stuff. I noticed in another thread you said there isn't one but valves instead. A specialist I spoke to on the phone said something about there being a luver type assembly.

Bodgit.

There are times Bodgit when I could cheerfully drop kick this computer through the window and when I have just written for some time and attached various files etc only for "windows to encounter a problem and need to close" is just one of them. Remind me to stop flying when Bill Gates gets involved with aircraft computers. Start again;

The error code P1251 is indeed turbo overboost. The boost pressure is controlled by a the variable nozzle which is really a radial gate which can be opened to increase flow or closed flat to reduce it. The gate is controlled by that vacuum unit sitting on top of the turbo. This pdf is actually for the 4.3 but explains it quite well;

Turbo 4.3.pdf

As your fault is intermittent, I would guess that the fault is not with the turbo hardware as generally that will either work or not work so it is more likely down to the control. The amount of boost is controlled by the VSV (vacuum sensing valve) or VRV (vacuum regulating valve) as it is sometimes referred to. It has come to light more recently that various turbo faults can be caused by this valve sticking and has been cured by nothing more than a squirt of WD40 to free the internal shuttle which controls the degree of vacuum to the vac unit - as determined by the engine ECU.

This VSV/VRV is located on a bracket near the end of the engine at the air filter side along with the turbo pressure sensor. Basically, the turbo pressure sensor tells the ECU what the boost pressure is and the ECU adjusts the pressure to suite various driving conditions by the VSV/VRV. This component regulates the amount of vacuum in the vac chamber and that pulls a link and works the variable nozzle. You can see the VSV in red and the turbo pressure sensor in green here;

Take the plug off the VSV, take note of the pipes and remove them then take the VSV off the bracket. Squirt a little WD40 into the holes and give it a good shake. Drain as much WD40 as possible out before refitting. There are electrical test which can be found in this link and it is a lot cheaper to try a new VSV than a new turbo!

http://www.toyotaownersclub.com/forums/index.php?showtopic=107303&view=findpost&p=997025

[Mach 1]

i would agree with Anchorman, sounds like VSV or VRV problems. The only thing I can add is that a turbo will give much greater boost when under it's greatest load. Therefore fifth gear whilst towing a caravan will create maximum boost pressure. If that boost is not controlled by the valves/solenoids then the overboost code and MIL will come on.

Lower gears and lighter loads may not create enough boost pressure to bring the fault on

[bothwell_buyer]

chuck the caravan and get a tent.

[Bodgit-fixit-run]

chuck the caravan and get a tent.

Had a trailer tent. Damned mouse ate it and left a beutiful doily pattern right through all the folds two days befor we were due to go away. Love to see one eat the van at least I can fix that and have done several times. Almost had a complete new frame now. Easier than tent as well. Just pull up and put the kettle on. It also got a door Bothey. I was thinking about adding more.

[Bodgit-fixit-run]

Done the valves guys as in lubricate them. Also had a feel of the turbo spindle; all appears well no felt play. Also sprayed up the vaccum link thingamybob as Alexander would say. Also did a service at the same time. The engine oil was really dirtuy so that won't have helped. New filters air oil and fuel. Plus a can of jet cleaner. Took it for a test spin all appears well. Tried to get it to throw a fault with some dodgy accellarator control but all seems well again. Will find out more at next outing with the caravan in a couple of weeks. Will let you know how it goes.

[bothwell_buyer]

chuck the caravan and get a tent.

Had a trailer tent. Damned mouse ate it and left a beutiful doily pattern right through all the folds two days befor we were due to go away. Love to see one eat the van at least I can fix that and have done several times. Almost had a complete new frame now. Easier than tent as well. Just pull up and put the kettle on. It also got a door Bothey. I was thinking about adding more.

a wee belated hahahahaha

I have just de-constructed our 3 ton caravan - the chassis gear is A! so intend turning it into a plant (ie industrial eqpt) tralier (dame this wireless keyboard)(

[Bodgit-fixit-run]

chuck the caravan and get a tent.

Had a trailer tent. Damned mouse ate it and left a beutiful doily pattern right through all the folds two days befor we were due to go away. Love to see one eat the van at least I can fix that and have done several times. Almost had a complete new frame now. Easier than tent as well. Just pull up and put the kettle on. It also got a door Bothey. I was thinking about adding more.

a wee belated hahahahaha

I have just de-constructed our 3 ton caravan - the chassis gear is A! so intend turning it into a plant (ie industrial eqpt) tralier (dame this wireless keyboard)(

Turn the keyboard over Bothey it works better.

TTFN

[ohphoto]

Heyup stranger!

Good to hear from you and sorry to hear about your misfortune.

I will have a trawl in the manual and see what I've got. The fact that it went away for such a long time makes me think it might not be anything fundamental so keep your fingers crossed.

Thanks for that Anchorman.

just to update you.

The fault is mainly comming up when towing a caravan. Leicester to Southport at the weekend. Three times each way all, on the motorway in 5th gear. Clear the fault and it runs ok for a while.

Just a bit confuse regarding the wastegate stuff. I noticed in another thread you said there isn't one but valves instead. A specialist I spoke to on the phone said something about there being a luver type assembly.

Bodgit.

There are times Bodgit when I could cheerfully drop kick this computer through the window and when I have just written for some time and attached various files etc only for "windows to encounter a problem and need to close" is just one of them. Remind me to stop flying when Bill Gates gets involved with aircraft computers. Start again;

The error code P1251 is indeed turbo overboost. The boost pressure is controlled by a the variable nozzle which is really a radial gate which can be opened to increase flow or closed flat to reduce it. The gate is controlled by that vacuum unit sitting on top of the turbo. This pdf is actually for the 4.3 but explains it quite well;

Turbo 4.3.pdf

As your fault is intermittent, I would guess that the fault is not with the turbo hardware as generally that will either work or not work so it is more likely down to the control. The amount of boost is controlled by the VSV (vacuum sensing valve) or VRV (vacuum regulating valve) as it is sometimes referred to. It has come to light more recently that various turbo faults can be caused by this valve sticking and has been cured by nothing more than a squirt of WD40 to free the internal shuttle which controls the degree of vacuum to the vac unit - as determined by the engine ECU.

This VSV/VRV is located on a bracket near the end of the engine at the air filter side along with the turbo pressure sensor. Basically, the turbo pressure sensor tells the ECU what the boost pressure is and the ECU adjusts the pressure to suite various driving conditions by the VSV/VRV. This component regulates the amount of vacuum in the vac chamber and that pulls a link and works the variable nozzle. You can see the VSV in red and the turbo pressure sensor in green here;

Take the plug off the VSV, take note of the pipes and remove them then take the VSV off the bracket. Squirt a little WD40 into the holes and give it a good shake. Drain as much WD40 as possible out before refitting. There are electrical test which can be found in this link and it is a lot cheaper to try a new VSV than a new turbo!

http://www.toyotaownersclub.com/forums/index.php?showtopic=107303&view=findpost&p=997025

Hi Anchorman.

First post on this forum. I have a 2003 Rav4 D4D. I Have been trying to fix the same problem as descibed by many on this forum. Intermittent erratic acceleration, occasional EML. Toyota diagnosed generic 34(2) turbo problem.

With the help of a mechanic friend I've checked the turbo, actuator, and all the pipes for faults and cleanliness. All seems good. So now I'm looking to replace the VSV. I stubbled upon this picture you've posted which seems to show two VSV's. The one circled in red and also the orangy/brown one which sits beneath the turbo pressure sensor.

According to the 'vsv layout.pdf' downloaded from the above link this is known as the 'VSV for Turbocharging Pressure Control'. I've checked on my own vehicle and this seems to be linked to the EGR system.

My friend also feels that the VSV you've circled in red is the more likely culprit of the two, but I'm trying to work out which part I need to order. I cannot get the part number and have already incorrectly purchased a turbo pressure sensor from Pentagon Toyota after requesting a 'Vacuum Sensor Valve'.

Whether changing this part will fix the problem is obviously unknown, but getting hold of one would be a start. This seems pretty tricky however, without the full name or part number for it.

Any help would be greatly appreciated.

[anchorman]

Hi Anchorman.

First post on this forum. I have a 2003 Rav4 D4D. I Have been trying to fix the same problem as descibed by many on this forum. Intermittent erratic acceleration, occasional EML. Toyota diagnosed generic 34(2) turbo problem.

With the help of a mechanic friend I've checked the turbo, actuator, and all the pipes for faults and cleanliness. All seems good. So now I'm looking to replace the VSV. I stumbled upon this picture you've posted which seems to show two VSV's. The one circled in red and also the orangy/brown one which sits beneath the turbo pressure sensor.

According to the 'vsv layout.pdf' downloaded from the above link this is known as the 'VSV for Turbocharging Pressure Control'. I've checked on my own vehicle and this seems to be linked to the EGR system.

My friend also feels that the VSV you've circled in red is the more likely culprit of the two, but I'm trying to work out which part I need to order. I cannot get the part number and have already incorrectly purchased a turbo pressure sensor from Pentagon Toyota after requesting a 'Vacuum Sensor Valve'.

Whether changing this part will fix the problem is obviously unknown, but getting hold of one would be a start. This seems pretty tricky however, without the full name or part number for it.

Any help would be greatly appreciated.

Hi ohphoto and congratulations on your first post - keep them coming.

There is quite a lot going on around that bracket on the end of the engine so I can see how you got confused but that orange component underneath as you say is the VRV (vacuum regulating valve) for the EGR (exhaust gas recirculation) valve! So many acronyms but you'll get used to them. Basically there are 2 systems using engine vacuum to control components and this one is an aid to emmissions. There is a valve which recirculates some of the exhaust back into the inlet manifold to balance the emmisions. You can see it bolted to the end of the cylinder head close to that group of valves and there is a diagram here;

vrv layout.pdf

For your problem you can safely ignore the orange one and turn your attention to the one I circled in red. This is the vsv (vacuum sensing valve) for the turbo and it uses information from the turbo pressure sensor (circled in green) to control that vac unit sitting atop of the turbo and that in turn controls the turbo output. There is a little electrical resistance check you can try here but keep in mind that somebody reported that it may be labelled the wrong way so the airflow is the opposite way. The main thing is that the resistance is OK, you can witness the operation of it closing the ports and that the shuttle is free to move;

vsv.pdf

Our parts man Parts-King will send one to your house at a discounted rate if pm him.

[ohphoto]

Many thanks Anchorman.

I shall let you no how I get on.

[saffron]

Hi Anchorman.

First post on this forum. I have a 2003 Rav4 D4D. I Have been trying to fix the same problem as descibed by many on this forum. Intermittent erratic acceleration, occasional EML. Toyota diagnosed generic 34(2) turbo problem.

With the help of a mechanic friend I've checked the turbo, actuator, and all the pipes for faults and cleanliness. All seems good. So now I'm looking to replace the VSV. I stumbled upon this picture you've posted which seems to show two VSV's. The one circled in red and also the orangy/brown one which sits beneath the turbo pressure sensor.

According to the 'vsv layout.pdf' downloaded from the above link this is known as the 'VSV for Turbocharging Pressure Control'. I've checked on my own vehicle and this seems to be linked to the EGR system.

My friend also feels that the VSV you've circled in red is the more likely culprit of the two, but I'm trying to work out which part I need to order. I cannot get the part number and have already incorrectly purchased a turbo pressure sensor from Pentagon Toyota after requesting a 'Vacuum Sensor Valve'.

Whether changing this part will fix the problem is obviously unknown, but getting hold of one would be a start. This seems pretty tricky however, without the full name or part number for it.

Any help would be greatly appreciated.

Hi ohphoto and congratulations on your first post - keep them coming.

There is quite a lot going on around that bracket on the end of the engine so I can see how you got confused but that orange component underneath as you say is the VRV (vacuum regulating valve) for the EGR (exhaust gas recirculation) valve! So many acronyms but you'll get used to them. Basically there are 2 systems using engine vacuum to control components and this one is an aid to emmissions. There is a valve which recirculates some of the exhaust back into the inlet manifold to balance the emmisions. You can see it bolted to the end of the cylinder head close to that group of valves and there is a diagram here;

vrv layout.pdf

For your problem you can safely ignore the orange one and turn your attention to the one I circled in red. This is the vsv (vacuum sensing valve) for the turbo and it uses information from the turbo pressure sensor (circled in green) to control that vac unit sitting atop of the turbo and that in turn controls the turbo output. There is a little electrical resistance check you can try here but keep in mind that somebody reported that it may be labelled the wrong way so the airflow is the opposite way. The main thing is that the resistance is OK, you can witness the operation of it closing the ports and that the shuttle is free to move;

vsv.pdf

Our parts man Parts-King will send one to your house at a discounted rate if pm him.

Ok, still trying to resolve the eml/limp mode problem. Have renewed scv's, checked vsv and vrv for correct electrical and mechanical operation, vac bellows/ actuator rod to turbo operating freely but problem remains, though sometimes intermittent. From other posts it would seem that the egr valve might be clogged so want to look at this next. Have searched the sight but can't find a thread on where it is or how to clean it. Can anyone advise please?

Thanks

[anchorman]

4.2 egr.pdf

Its a dead simple valve operated by vacuum. When you take it off see if you can blow through the ports before you do anything to see if is stuck open. Eitherway, clean it out and try to apply vacuum to the chamber to see the unit is working. If it is stuck shut it is unlikely to cause any problems but will if it is sticking open.

You have replaced the fuel filter before you started all this?

BTW, can you change your profile as it says 2.2 which isn't right and sometimes confuses me when I am looking at so many

[Bodgit-fixit-run]

4.2 egr.pdf

Its a dead simple valve operated by vacuum. When you take it off see if you can blow through the ports before you do anything to see if is stuck open. Eitherway, clean it out and try to apply vacuum to the chamber to see the unit is working. If it is stuck shut it is unlikely to cause any problems but will if it is sticking open.

You have replaced the fuel filter before you started all this?

BTW, can you change your profile as it says 2.2 which isn't right and sometimes confuses me when I am looking at so many

I cleaned all the bits round there as I was taking it to bits anyway. All still going well. Taking the caravan out next week which will tell. I also serviced the car so oil and filter change, air filter and fuel filter change with jet cleaner put through as well. It certainly seems to be starting easier now, so I am hopeful this is it for now at least. Just a qyuick tip. keep your fault reader in the car cos then you can reset the fault code if it comes up, however check it is the same one each time. Thats how I got home last time.

[saffron]

4.2 egr.pdf

Its a dead simple valve operated by vacuum. When you take it off see if you can blow through the ports before you do anything to see if is stuck open. Eitherway, clean it out and try to apply vacuum to the chamber to see the unit is working. If it is stuck shut it is unlikely to cause any problems but will if it is sticking open.

You have replaced the fuel filter before you started all this?

BTW, can you change your profile as it says 2.2 which isn't right and sometimes confuses me when I am looking at so many

Anchorman, sorry for the confusion. Can't think where the 2.2 came from. The car is the 2005 model with the round spotlights and the 1995cc 1CD-FTV engine according to the handbook. Replaced the fuel filter at 40,000 miles when the fault first appeared to no effect. Replaced again at 45,000 also to no effect. Both times I used the genuine Toyota part. Car is now coming up to 50,000 miles so can't hurt to try again.

Thanks for the PDF. I'm probably being stupid but I can't identify on the engine a component that resembles the diagram in the PDF. Can you advise where the egr is on this engine?

Incidently, had the cam belt changed by the main dealer at £280 which I thought was not too bad???

[anchorman]

You shouldn't need another fuel filter for a while yet but as these things are often overlooked, I thought I would check. If you look at posts 13 or 15 above for the VRV layout, just follow the vac pipe back to the end of the cylinder head and you will see the EGR with vac unit sat on top. Maybe this will help - look for EGR in the bottom RH area!

£280 for the timing belt was a good deal as it is a fiddly job to say the least.

EGR loc.pdf

[saffron]

You shouldn't need another fuel filter for a while yet but as these things are often overlooked, I thought I would check. If you look at posts 13 or 15 above for the VRV layout, just follow the vac pipe back to the end of the cylinder head and you will see the EGR with vac unit sat on top. Maybe this will help - look for EGR in the bottom RH area!

£280 for the timing belt was a good deal as it is a fiddly job to say the least.

Anchorman, many thanks for your very prompt response.

The diagrams in the VRV layout pdf, egr loc.pdf and your diagram are different to my engine. They show the VRV inner pipe connected via the vacuum damper to a round bellows type device labelled EGR which is shown via dotted lines bolted to the lower part of the cylinder head.

On my engine, this pipe (with vacuum damper) is connected to the round bellows sitting on top of the turbocharger which actuates the variable vanes. The outer pipe is connected to a component directly below which I assume is a vacuum source as there is a larger rubber pipe coming from this to the brake servo.

Also, the pdfs show the air filter mounted left to right and what presumably is the Battery, located in front of it, wheras my model has the Battery hidden up near the windscreen and the air filter in the front mounted front to back. The VSV (below the turbo pressure sensor) has a pipe running to a connector in the inlet manifold directly below the top radiator hose.

Basically, my engine layout looks exactly the same as shown in your photo in post #5 so maybe the pdf’s are for an earlier or later model?

[anchorman]

The photo further up in the thread comes from Wollastons 2005 RAV and his Battery is where yours is - under the front scuttle. However, his has that orange VRV in the photo and yours should have to so follow the vac pipes back to find the EGR valve. I'm working blind as I've looked through all my stock photos but if you want to take me a couple of photos of the engine on that side I will point it out.

[saffron]

The photo further up in the thread comes from Wollastons 2005 RAV and his battery is where yours is - under the front scuttle. However, his has that orange VRV in the photo and yours should have to so follow the vac pipes back to find the EGR valve. I'm working blind as I've looked through all my stock photos but if you want to take me a couple of photos of the engine on that side I will point it out.

Thanks Anchorman,

Sorry for being so confused (situation normal for me these days!!) I have attached some photos (with air filter removed) as requested to help identify the EGR.

In your EGR 4.2 pdf this shows a valve labelled E-VRV with two ports next to each other and the filter port at the other end . The outer pipe goes to a unit directly below it (which has several other pipes connected to it), and the inner port (with the green vacuum damper) going to the EGR valve lower down on the engine. As can be seen from the photos, this is the same on my engine with the exception that on mine the inner pipe goes to the vac unit on the turbo and not the EGR.

The same pdf then shows a valve labelled VSV with a port at each end and a port on the top. On my engine this is the orange/brown one which is connected to the turbo pressure sensor on top of it. One port is then connected to the inlet manifold at the front of the engine and the other port has a filter on it.

I can’t identify a component that resembles the EGR diagram shown in the pdf. Thanks for any light you can shed on this

[codswallop]

Saffron - your EGR valve is electrically operated like the one on my wife's Verso. In your photos it is the 'canister' shaped unit (to the left/forward of the vacuum pump) with two pipes connected to it, which carry coolant to cool it (you will need to block these if removing).

[anchorman]

Saffron - your EGR valve is electrically operated like the one on my wife's Verso. In your photos it is the 'canister' shaped unit (to the left/forward of the vacuum pump) with two pipes connected to it, which carry coolant to cool it (you will need to block these if removing).

Brilliant! Thanks Codswallop - thats what happens when somebody bggrs off on holiday with your sample 4.2 diesel!!!

Of course a new water cooled EGR was introduced;

New 4.2 EGR feature.pdf

New 4.2 EGR.pdf

New 4.2 EGR test.pdf

You can test a few things and maybe clean it out but you might have to clamp the hoses and disconnect them.

[saffron]

Saffron - your EGR valve is electrically operated like the one on my wife's Verso. In your photos it is the 'canister' shaped unit (to the left/forward of the vacuum pump) with two pipes connected to it, which carry coolant to cool it (you will need to block these if removing).

Brilliant! Thanks Codswallop - thats what happens when somebody bggrs off on holiday with your sample 4.2 diesel!!!

Of course a new water cooled EGR was introduced;

New 4.2 EGR feature.pdf

New 4.2 EGR.pdf

New 4.2 EGR test.pdf

You can test a few things and maybe clean it out but you might have to clamp the hoses and disconnect them.

Hi CW and Anchorman,

Many thanks for your responses. I knew the EGR had to be in there somewhere. I’ll have a go at it over the next few days. Any tips from anyone on how to proceed gratefully received.

I’ve lived with the problem for a year now and the EGR is my last hope before gritting my teeth and having Mr T fit a new turbo.

My dilemma is that with just under 50,000miles, gold and silver metallic paintwork, two-tone leather interior, brand new bridgestones all round, new cambelt and full service history, the trade-in value at Mr T is only about £4K. A turbo replacement would be about half this but would add no value to the car. BUT, we love the RAV.

My only hope is that, because the problem is intermittent (occasionally it runs like new) I’m hoping it’s not the turbo.

Thanks again for your help.