Overboosting 1.3 multijet JTD

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Overboosting 1.3 multijet JTD

AlfaFiat25

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Hi everyone .

I have ran into a problem with my 1.3 jtd multijet . I’ve heard the wastegate actuator blow off when changing gear at low rpm for a few days then it threw up P0234 (turbo over boost ) and P2563 (boost control position sensor A circuit Range / performance). Exhaust note changes and uses a lot of fuel , I expect because it’s not burning it. You can reset the codes but the performance is still affected and the lights will come back on eventually.

I first checked the actuator lever and this was operating by hand and getting the full travel .
I then did a Vac test on the actuator and it held vacuum .
Then vac tested the vac pipes from there to the boost switch and then to the vac tank and then to the vac pump . I can’t find a fault in that system with the vac test.

I did change the boost control solenoid / valve as I had access to a Combo Van but alas the fault continued even though I did think it initially fixed it for about 10 mins .

The actuator itself is fully down at turn off and fully opens for a second when you turn the key and goes back to home position.

Can anyone help me with narrowing down the problem ? Or if I am missing something on my test ?

Even though the EGR isn’t on this vacuum circuit could this be worth looking at or if there was a problem with it would have threw up an EGR code ?

It’s the engine that doesn’t have the small vac pipe joining the actuator to the turbo .

Any help would be appreciated . I could guess a few things but it would just be guessing so abit of expertise would be brilliant .

Thanks
 

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Hi everyone .

I have ran into a problem with my 1.3 jtd multijet . I’ve heard the wastegate actuator blow off when changing gear at low rpm for a few days then it threw up P0234 (turbo over boost ) and P2563 (boost control position sensor A circuit Range / performance). Exhaust note changes and uses a lot of fuel , I expect because it’s not burning it. You can reset the codes but the performance is still affected and the lights will come back on eventually.

I first checked the actuator lever and this was operating by hand and getting the full travel .
I then did a Vac test on the actuator and it held vacuum .
Then vac tested the vac pipes from there to the boost switch and then to the vac tank and then to the vac pump . I can’t find a fault in that system with the vac test.

I did change the boost control solenoid / valve as I had access to a Combo Van but alas the fault continued even though I did think it initially fixed it for about 10 mins .

The actuator itself is fully down at turn off and fully opens for a second when you turn the key and goes back to home position.

Can anyone help me with narrowing down the problem ? Or if I am missing something on my test ?

Even though the EGR isn’t on this vacuum circuit could this be worth looking at or if there was a problem with it would have threw up an EGR code ?

It’s the engine that doesn’t have the small vac pipe joining the actuator to the turbo .

Any help would be appreciated . I could guess a few things but it would just be guessing so abit of expertise would be brilliant .

Thanks
Any chance DPF blocked?
If you were getting black smoke I would have said check for air leaks between turbo and inlet to head.
Is it a basic code reader or MES or similar?
 
Any chance DPF blocked?
If you were getting black smoke I would have said check for air leaks between turbo and inlet to head.
Is it a basic code reader or MES or similar?
Hi there thanks for the reply , it's behaving differently than a normal dpf regen . I haven't checked the DPF percentage but can do , haven't had the light on for that though. The black smoke isn't extreme it's just a puff now and then that I was putting down to over fuelling . The code readers were firstly a vague cheap one and then my friends snap-on one . He checked the live readings when driving but when he did that it wasn't in limp mode. I'll check the DPF and report back. 👍
 
Hi there thanks for the reply , it's behaving differently than a normal dpf regen . I haven't checked the DPF percentage but can do , haven't had the light on for that though. The black smoke isn't extreme it's just a puff now and then that I was putting down to over fuelling . The code readers were firstly a vague cheap one and then my friends snap-on one . He checked the live readings when driving but when he did that it wasn't in limp mode. I'll check the DPF and report back. 👍
Also with your friends Snap On tool you can activate EGR and other things to test further.
My thoughts were if DPF blocked it could build up pressure at the inlet and turbo as no where for pressure to go.
Sometimes blocked DPFs knacker turbos for that reason.:)
 
Thought I would get time to get at it again today but ran out of time as per usual ! I’ll get a day at on Saturday to check the above .
It did to a regen recently and the dump / blow off noise is still audible when low down in revs in 2nd, almost like a high pitched burst whistle. But like advised I’ll plug it in to see exactly what % the DPF is on.
 
Thought I would get time to get at it again today but ran out of time as per usual ! I’ll get a day at on Saturday to check the above .
It did to a regen recently and the dump / blow off noise is still audible when low down in revs in 2nd, almost like a high pitched burst whistle. But like advised I’ll plug it in to see exactly what % the DPF is on.
It's not an air leak on the pressure side of turbo/intercooler/hoses?
 
Thanks guys , I did inspect this area , I'll do it again thoroughly. That the thing with the wooosh , I'm guessing it's the blow off but I can't check standing Infront of the engine bay as it's not under load . Ill have another look 👍
 
Thanks guys , I did inspect this area , I'll do it again thoroughly. That the thing with the wooosh , I'm guessing it's the blow off but I can't check standing Infront of the engine bay as it's not under load . Ill have another look 👍
It does sound like well worth checking all the turbo pressure side from turbo to hoses to intercooler and finally the hose to the inlet manifold.
Sometimes as @Steve gt mentioned the metal pipe cracked, also hoses can have a split that lets go as pressure builds.
There are a couple of ways to technically test that. 1. I did with a kit of blanks that you fit to either end and pump air pressure to around 20 psi , on mine that showed a couple of hoses that needed new clips.
2. Is a smoke detector/generator that with engine off is forced into the turbo pipe and it is possible to see any leaks as it gives off white smoke.
On a 1.6 Doblo I had a lot of issues along your line and eventually that final test showed a EGR pipe fitting at the inlet manifold needed a new gasket and bolts.
The cheap way if you are lucky is get your mate to rev it up whilst you listen under the bonnet to locate the source .
Sometimes also it may show as a oil stain on a turbo hose etc.
 
Hi guys , first of all thanks for all the input so far , it's appreciated especially being a new member.

Right today I checked the intercooler to intake pipe and gave it a visual inspection and everything seems fine . With it being a 17 plate its pretty clean under there. I'm not set up to do a pressure test of that so visual was done.

Dpf and egr are working correctly according to the diagnostic equipment that was more advanced than mine. Dpf was at 40% or so .

I did a vacuum test on the actuator again and the vacuum pulls the lever down holds pressure and then when I release the vacuum it goes back to starting position, both ways are without hesitation so to me the vanes in the turbo are fine and also the actuator itself.
I tested the pipe from the vacuum / electro switch to the vacuum tank and to the vacuum pump, it also held vacuum .

I had to borrow someone to rev the car while I stood at the front to see the actuator working. This person was rough with the pedal 😂 so while I was nose to nose with the engine I heard the blow off noise for the first time while not driving. It was straight out the air box area.
This put the car into limp and P0234 code up ( overboost condition ) as per before.
The lever and actuator behave / move differently than just with the vacuum gauge test . I did film this I'll try and attach it. The solenoid / electro valve that I replaced from a vauxhall combo can't be guaranteed so it could also be faulty but again no way to test.

Hopefully someone can look at this and tell me what's next . My head is a bit fried with it .

Thanks again
 
In the last video there looks to be a lot of soot around the actuating lever on the turbo, is it possible when under heavy boost it is leaking out of there and making the whistling noise?
It could be the turbo is stuffed and you may be able to get a replacement cartridge for it. I fitted one on my 1.6 MJ, though on mine it was blowing oil past the impeller and burning it. It took a while to get the oil from the intercooler.:)
Maybe get your mate to rev it hard again and hold a old rag over there to see if it quietens it to pin point the noise.
 
Hi there , like I said the dump noise is coming from the air box ( first few seconds of the first video) . Yeh I did see that soot but it's just dirt stuck to silicon that's been sprayed over the plastics probably or similar . No leaks etc .
Turbo is working 110%
 
Hi there , like I said the dump noise is coming from the air box ( first few seconds of the first video) . Yeh I did see that soot but it's just dirt stuck to silicon that's been sprayed over the plastics probably or similar . No leaks etc .
Turbo is working 110%
Can you get your mate to replicate the noise , but with you using a long screwdriver to your ear held against the turbo and other areas to locate the noise.
It is not a normal "dump noise" and I suspect it is related to wear or damage on the flap and spindle that controls it on the turbo housing where that actuator shuts the valve against the exhaust gas.
I am not saying the turbo isn't working really well, but maybe too well!
So when it actuates to reduce pressure there is a higher amount of pressure than normal.
So when it happens and fault code come up it puts it into "limp mode".
Do you see any black smoke, if not then the extra pressure/oxygen is burning all the fuel so no black smoke.
Can you get accurate readings of the manifold pressure with your diagnostic tool?
If there is no damage to the turbo then maybe you can adjust the actuator lever to "dump" earlier and reduce the amount of pressure.
It's not easy to get to, but I am guessing if the rod is shortened it will be pulled back off by the suction from the actuator vacuum earlier.
Whilst working there see if any sideways movement at that spindle in turbo as it is not normal to see soot around there.:)
 
Thanks for the reply .
The turbo doesn't have a flap it's a VNT .....
Also the vanes are working smoothly and I don't see a problem with the turbo at all. The actuator doesn't have the adjustment nuts .
MAP readings are within the parameters , The "Soot" could be from a previous leak from exhaust or oil pipe or detailing silicon collecting dirt. It's done 70k and 8 years old.

My focus is really on the vac system operating the actuator. Especially that when I fitted a solenoid from a vx combo it cured it , even though it was for only 10 mins. I can't vouch for the solenoid that I fitted so I'm thinking it's failed and probably not the correct part for the job . I have ordered another one tonight that is actually for my car ( managed to get an OEM one new for £25 )

Tomorrow I'm going to fit the vac gauge inline from the solenoid to the actuator and run / idle / turbo . And take some readings and see what the needle does when the solenoid should/shouldn't be working. If it's sticking or not I should see it on the gauge. I'll do the same when the new solenoid arrives .

I'll get back on here when I have made about of progress.
 
Thanks for the reply .
The turbo doesn't have a flap it's a VNT .....
Also the vanes are working smoothly and I don't see a problem with the turbo at all. The actuator doesn't have the adjustment nuts .
MAP readings are within the parameters , The "Soot" could be from a previous leak from exhaust or oil pipe or detailing silicon collecting dirt. It's done 70k and 8 years old.

My focus is really on the vac system operating the actuator. Especially that when I fitted a solenoid from a vx combo it cured it , even though it was for only 10 mins. I can't vouch for the solenoid that I fitted so I'm thinking it's failed and probably not the correct part for the job . I have ordered another one tonight that is actually for my car ( managed to get an OEM one new for £25 )

Tomorrow I'm going to fit the vac gauge inline from the solenoid to the actuator and run / idle / turbo . And take some readings and see what the needle does when the solenoid should/shouldn't be working. If it's sticking or not I should see it on the gauge. I'll do the same when the new solenoid arrives .

I'll get back on here when I have made about of progress.
When I worked on my daughters Golf GTD 130 Hp with VVT hers was going into limp mode due to sticking vanes and after freeing off the lever would go all the way in both directions to the stops. From memory at one end there was a screw thread and lock nut to control extent of travel.
Do you have anything like a Mity Vacuum pump/gauge tool that you could plug into feed to turbo actuator rubber pipe and control it as you rev and release etc.
The other interest would be to see what the turbo boost pressure actually is using a manual pressure gauge, when compared with the details on your friends Snap On tool for max boost reading.
Is it possible to take the inlet hose from air filter off so you can waggle the spindle of the turbo impeller as if a lot of movement the blades can make a noise against the housing.
 
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