ok please bear with us on this one.

i got a turbo fitted last week from a breakers as mine is shot (td05 16g) and it was a straight replacement. it was fine for about a week boosting as per normal then one day i went to put my foot down and nothing, as soon as the car hit 0 psi at around 3k revs it went all jumpy, it was odd as it seemed like the car wanted to go but it never did.

the car was fine to drive under 3k revs for a few days but then it started to misfire and it became very bad very quickly and it almost conked out when i was on the way home the only way i made it was by revving it in neutral and trying to rev it as hard as i could when it got past around 4k revs it was popping like mad as it was trying to clear the system of fuel, i did make it home but only just and it was truly shocking how it was misfiring.

what is the likely cause of this as i have ordered a new maf sensor as i no when these go these are the symptoms of it.

my coil pack is 10yrs old and my spark plugs and leads were changed around 18 months ago.

i have an avcr which i have turned to off so i was hoping to see if that was the problem and just run the wastegate pressure but that didnt help either.

is there anyway of testing the coil pack to see if its shot and would it be avisable to get some new plugs or just clean my up, and how do you test the leads?

 

From the description you give of when it first happened, it sounds very much like you're turbo hose has blown off.

Definitely worth checking.

 

From the one experience I've had of blowing an pipe off, it's just stalls.

Check all the pipework though, bit awkward if still have a top mount though.

Have you checked the fault codes, assuming a standard ECU?

 

You're right micky, i was referring to this part of the op's post rather than when it first happened.


It's possible that the hose had partially came off before it completely removed itself. It would tie in with the turbo just being changed, and thats the first thing i would be checking.
If the hoses are ok, pull all the spark plugs and check for obvious signs. A wet plug would indicate that it has'nt been firing on that cylinder.

 

This defo sounds like a turbo hose issue. It may just have a small split in it which would allow the car to drive fairly normally up until the point where the split is forced open. This could also be the case with a hose clip not properly tightened. Whipping the top mount intercooler off is not a massive job.
Check the turbo to intercooler "Y" pipe and also the Intercooler to throttle body hose.

Your problem could also be due to the turbo sucking in air after the maf sensor which will be unmetered. Just check everything from the maf sensor to the throttle body. If its not a hose then we'll have a look at other possible causes.

 

ma ma sita

 

i will check the hoses again but i havent had time to check the main y pipe.

thanks for the replys i will keep you informed of how things go

 

what about the actuator bar ? my rs turbo done the same and it was that .

 

my money on the pipework as I had similar once when I had a topmount. The plastic gets brittle and can split even though it may look okay.

check hoses and also make sure the downpipe is tight (assuming thats ok though as no mention of blowing)

 

i have been told about the actuator but how do i go about checking it?

i have a samco y pipe so it really shouldnt split.

how many pipes are there to check to do with the turbo cause the only ones i can think of are the 2 pipes from the avcr and the i/c pipes.

daz, how can i check the turbo is sucking in air after the maf sensor.

i started the car last night and it started fine kept it in neytral and just revved it to about 5k revs it seemed to be ok but you could also sense the car wanted to start popping from the exhaust

 

I had similar problems on my last scoob. I took it to Triton in B'mouth,they charged me £330 to change all the coil packs,and diagnose the fault,and didn't make any difference(robbing gits,one of many problems i had with them). I ended up taking the tmic off,and found the hose on the bottom was split. Replaced it,ran fine.

Mit

 

ok a little update, a few days ago i took off my maf sensor and spark plug leads for a few days as i was going to to check he plugs but due to me finishing late and the weather i never had a chance so i just reconnected everything and thought i would start it up to see how it ran on idle, and it works on idle no lumpiness or nothing.

i took it out today and kept it under 3k revs and th car seemed to drive fine no misfires or nothing so i thought great lets see if the turbo is working is working properly again but alas no still the same problems as before.

i think maybe a lead had come slightly lose as i had this happen before and my leads are very short and dont hav much slack when the engine is pulling, anyway here is the biggy i may have found my problem but what do you all think.

i took off the i/c today and checked the y pipe and noticed this slash mark on the pipe, it has cut the red outside as you can see but doesnt look like its gone through to the blue part but maybe there a tiny holes in the blue i cant see, question is is the air coming out off here?

 

bttt for help needed

 

If you rev the engine from under the bonnet whilst holding one of the boost hoses you should be able to feel the hose "swelling" (). This at least will give you an indication that the turbo is creating boost and that boost isn't leaking off somewhere.

 

i take it you mean the 2 pipes from the avcr

 

Any of the flexible hoses that you can get your hand on that are after the turbo outlet should show some sign of boost. The problem is you have to do this with the system complete of course...

 

ok cheers will try that today

 

ok another quick update, i took my y pipe and put the split peart of it in some water to test for leaks like you would do with a bike tyre and it was fine no bubbles what so ever so i can only assume the pipe is ok.

when i put the i/c back on one of my leads had come off at the coil pack so i went to put it back on then noticed this.





its numbers 3 and 4 that are like this and number 4 is the worse. i checked the ends of the leads and 3 and 4 had turned this colour as well but not as bad as the coil pack.

i take it i need a new pack and leads but could this cause my turbo not boost up because the pack and leads arent supplying enough power

 

looks like corrosion caused by water getting into the coil pack. give it a good clean up and see if it improves

 

just an update, i have changed my coil pack,leads and maf sensor and the car seems to be running fine, no hesitation or misfiring but the turbo only gets to to around 15 psi, would my avcr or turbo need adjusting as this is a new turbo after mine went **** up, or as from the pics above would it be worth changing the y pipe.

when you accelerate its like the car has been tuned to 15-16 psi and i have changed the settings the avcr between a, b, and turning it off

 

ok how wrong was i im actually only getting between 5-6psi but when you look at the avcr the boost always stays at -760 and never moves yet the car is boosting but only to 5-6 psi when it should be hitting 21 psi what the hell is causing this cause when i change screens and watch the graphs page you can see the boost graph going up