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Vw Passat , B5 problems with turbo pressure.

Mar4ix

Hey folks, passat b5 , 2001 ,what i am working on here, feels very sluggish , turbo kicks in only after 2.5 k revs. there is million and one reason, but what i checked is , there is no intercooler leaks, vacuum does work , no any faults on ECU (checked with original vag-com) . when rev up , pipes barely get some pressure.

On NCT passed smoke and all other relevant tests. failed only on minor things.

Could be veins stuck ? or turbo actuator ? turbocharger itself ??

there is no weird sound nor any kind unusual smoke.

( i was cleaning inlet manifold and EGR .. them was completely blocked with soot, which i successfully cleaned, previous owner must be never rev it up at all. )

running out of ideas.

Ta.

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George Dalton

Do you have vacuum at the actuator on the turbo?

When you start the engine does the actuator arm move up?

Chimaera

If you have a hand operated vacuum pump, you can apply it to the VNT actuator and see if it moves. If the intake and EGR were that clogged up, I'd be thinking clogged VNT vanes.

Mar4ix

yea, i am thinking about same, i dont have hand operated vacuum pump, but will try work around first with simple checks, my friend have absolutely same car, will swap some sensors , see if any changes, if i wont find fault, will have to take turbo charger off, see what i can do.

Personally i think it is veins, because car seems to be never revved up, clogged egr and inlet manifold show this. first will check turbo charger solenoid, actuator, and then will start work on turbocharger.

Any one have a guide how to clean up veins ? is that turbocharger off, split exhaust side ? never done it before, but always we do first time, and learn.

elizaharry

Probably the Hoses/Pipes incorrectly connected, disconnected, leaking or Charger Pressure Control defective.

Mar4ix

elizaharry wrote: »

Probably the Hoses/Pipes incorrectly connected, disconnected, leaking or Charger Pressure Control defective.

Usually leaking pipe/hose makes hissing noise, but in my case there is non any. Will check with other same passat vacuum pipe connections, make sure mine is correctly connected. , and will replace some sensors if there will be no change, ill take turbo off for vein cleaning.

Mar4ix

Ok, some updates. It was a while, i couldnt get my hand on , as I was busy a bit.

Yesterday was driving for whole day, eventually turbo charger didnt kick in at all.

I've took off air pipe at turbo. turbocharger feels like new, spins smoothly, no any move sideways.

vein actuator moves up and down without problems.. with some tension, but no need to push too hard , to push it up , from underneath car. , so thats not actuator, then i checked vacuum line ... no vacuum, at all. checked vacuum at the vacuum pump , there is vacuum, but i dont know how strong it suppose to be.

then while troubleshooting vacuum lines, found solenoid behind airpipe behind engine, replaced that with good known sensor (my friend has passat also), no any changes, no vacuum. I've replaced all vacuum pipes, which looked suspicious , no changes at all.

My friends passat vacuum power at vacuum pump is similar.

Any idea where to look at ? would be broken hard vacuum line somewhere ?

I am planing pull out all vacuum lines , and properly check.

EDIT:

vagcom doesnt show any faults.

Mar4ix

another way how i checked turbo actuator, i just suck air from pipe, and actuator arm rises up. deffo cant be actuator problem.

i have closed brake master cylinder pipe.

while engine is working , both vacuum actuators become warm, assume they are working. i have checked voltage, on that one, which is at the back (behind air pipe), has 13.5 V in connector. , that one which is at the turbo charger, gives out 10.3 v. Dont know is that normal.

still no luck with vacuum.

actually i have feelings, that vacuum stops after that actuator behind air pipe.

Mar4ix

I have checked vacuum line to egr, just blow in vacuum line from actuator, air passes freely , both direction, would that mean egr valve is broken, and rob my vacuum ?

darragh o meara

There is a valve on the front of the engine. Usually has a white cap and a few vac pipes going into it. The pipes have a habit of cracking and causing similar probs to those you mentioned.

I found cracks in the bend if mine.

Mar4ix

So some stuff came clear now to me. I found vacuum line picture, will post here , in case somebody will want to find.

After I bought vacuum tester, had more chances to find problem, seems to be turbo vacuum solenoid died, and egr solenoid opens just half way. so , both solenoids are gone

. time for shopping

Handy site for doing some work on passats, just in case somebody needs to do some work. https://sites.google.com/site/1810martin/

As promised, vacuum line diagram for VW Passat B5.

Mar4ix

question to George ? maybe somebody else could answer.

So i have diagnosed both vacuum solenoids faulty. At the moment i have one connected for turbo charger (which was on egr vacuum line) , and other one is disconnected from vacuum pipes, as those i have connected directly.

When i checked with my friends passat , vacuum on turbo charger actuator pipe was 300 mmHgvac , on mine that one which is now for turbo, get only 200 mmHgvac , when check vacuum directly on vaccum pump, mine one produces even better vacuum than my friends one.

question is:

Obviously that egr and turbo solenoids look absolutely identical. Are they identical, or they are different mechanically or electronically inside ?

As when i had egr solenoid, it didnt gave more than 200 mmHgvac , so when turbo solenoid was working, it couldnt get more vacuum , was the reason, that turbo kicks in only after 2.5 k revs.

Can i skip turbo solenoid also , make turbo actuator connected directly from vacuum pump, but i assume, turbo charger will be open all time, is that bad idea ?

Chimaera

The turbo should not be left uncontrolled. You know those two solenoids are bad, replace them first and see if the problem is cured. If not then you can continue with further diagnosis.

Mar4ix

Chimaera wrote: »

The turbo should not be left uncontrolled. You know those two solenoids are bad, replace them first and see if the problem is cured. If not then you can continue with further diagnosis.

well , the system is so simple, maybe its look complicated.

It took for me good few hours with vacuum tester to find out how does it work, but now i am familiar with vacuum lines and its system in passat, a specially if i can access car with properly working system, and compare with mine.
Simplest way would be just put from other car solenoids, and put in my, and see if car working fine ( i have no access to other car right now, but will be in evening or tomorrow morning) .

If it will struggles open solenoids, so it will be electronic fault, which will leads to replace ecu (after readings in other forums).

As i wrote earlier, on egr valve solenoid there 13.5 v in connector, and on turbo one 10.5 v , while engine is running, but egr valve acts absolutely same when connected on turbo place . (as i still use egr valve in turbo valve place (as turbo one is gone completely ) , but it opens only on half ish) .

still question stands for - is there mechanical or electronic difference between turbo and egr valves , as when ill be going to scrapyard, might there will be two faulty egr, and two good turbo ones, or other way.

I did read in other forums, that i can use egr solenoid to put in turbo one place, to see if turbo one faulty.

after rambling around different part shops, part numbers are different. might somebody have access to ETKA and see if they are really different.

Chimaera

Those solenoids are wear items: chances are any you find in a scrapyard are dead or nearly dead so they're a waste of time and money. Spend the money on new ones and you're not worrying about them then. I can't recall if they're the same on the Passat or not: some of them on some models are interchangeable but I don't have the ability at work to check part numbers to confirm this. Some things aren't worth cheaping out on really - you're only inviting more hassle.

Mar4ix

Chimaera wrote: »

Those solenoids are wear items: chances are any you find in a scrapyard are dead or nearly dead so they're a waste of time and money. Spend the money on new ones and you're not worrying about them then. I can't recall if they're the same on the Passat or not: some of them on some models are interchangeable but I don't have the ability at work to check part numbers to confirm this. Some things aren't worth cheaping out on really - you're only inviting more hassle.

I wish i could afford new ones, even they new ones wont be way over 50 quid each , but budget is very tight, and by time being will try get used ones, a specially if scrapyard may swap to another one, if bought one is dodgy .

ardle1

Mar4ix wrote: »

well , the system is so simple, maybe its look complicated.

It took for me good few hours with vacuum tester to find out how does it work, but now i am familiar with vacuum lines and its system in passat, a specially if i can access car with properly working system, and compare with mine.
Simplest way would be just put from other car solenoids, and put in my, and see if car working fine ( i have no access to other car right now, but will be in evening or tomorrow morning) .

If it will struggles open solenoids, so it will be electronic fault, which will leads to replace ecu (after readings in other forums).

As i wrote earlier, on egr valve solenoid there 13.5 v in connector, and on turbo one 10.5 v , while engine is running, but egr valve acts absolutely same when connected on turbo place . (as i still use egr valve in turbo valve place (as turbo one is gone completely ) , but it opens only on half ish) .

still question stands for - is there mechanical or electronic difference between turbo and egr valves , as when ill be going to scrapyard, might there will be two faulty egr, and two good turbo ones, or other way.

I did read in other forums, that i can use egr solenoid to put in turbo one place, to see if turbo one faulty.

after rambling around different part shops, part numbers are different. might somebody have access to ETKA and see if they are really different.

1JO 906 627:(N18) EGR solenoid return valve..... 1JO 906 627 A : (N75)Turbo solenoid return valve.. I dont think there is any difference!!
AVB,AVF,AWX Engines,.... I have same problem a long time now, head wrecking.. You can test these Solenoids with 2 wires from your battery, touch both connectors and listen for a 'pop'. If you hear a pop each time you make a connection then the unit is good.

Mar4ix

ardle1 wrote: »

1JO 906 627:(N18) EGR solenoid return valve..... 1JO 906 627 A : (N75)Turbo solenoid return valve.. I dont think there is any difference!!
AVB,AVF,AWX Engines,.... I have same problem a long time now, head wrecking.. You can test these Solenoids with 2 wires from your battery, touch both connectors and listen for a 'pop'. If you hear a pop each time you make a connection then the unit is good.

Thanks mate. I was connecting and disconecting them while engine running( i know, thats will log a fault, but i have no problem clear it) , no any sound went off egr valve( which is half alive) , and continious buzzing sound from turbo solenoid, which stopped, when close one of vacuum line and then release.

ardle1

Power does not run continuously to the return valves, only when message is sent from ECU, so it's better to test direct from battery!

Mar4ix

Just off visiting my friend with properly working solenoids, at idling vacuum was 100 those vacuum units, when rev up it jump for mili second to 150 , and dropped back to 100. nothing really changed, even worse, it just went in kind limp mode, no power in any rev range (no any lights in dash though). diagnostics showed vacuum negative deviation, or something.

So more likely there is electronic fault.

Any one have idea, how to get it fixed ?

ardle1

Sounds like fault code 17964..... Anything from a vacuum leak, faulty return valve, loose hose clip, clogged Turbo veins etc, or as you say electronic fault !!! Have you checked your intercooler! I cleaned mine with full can of Carburetor cleaner and good rinse with water(made no difference btw), also some people say a clogged catalytic converter can cause similar problems.....

Mar4ix

ardle1 wrote: »

Sounds like fault code 17964..... Anything from a vacuum leak, faulty return valve, loose hose clip, clogged Turbo veins etc, or as you say electronic fault !!! Have you checked your intercooler! I cleaned mine with full can of Carburetor cleaner and good rinse with water(made no difference btw), also some people say a clogged catalytic converter can cause similar problems.....

Thanks for your input.

Was talking with guy , who is advanced in car diagnostics (had to call back home) , after i told him what i did, he said, that ... typically is very very rear that ecu on these cars getting broken, he even dont know any in his working time, but he agreed, it does look like ECU fault.

I will have another attempt do computer scan in one garage (maybe access ECU maps) see what the story there, if no look, will be looking for another ECU. Already found out complications about adaptation, but there is one way around.

ardle1

Any joy... I think I know off a guy who might have ECU(USED) and very good price..... http://stores.ebay.ie/car4parts?_trksid=p2047675.l2563..... also some interesting sites http://forums.tdiclub.com/showthread.php?t=346842 ... http://www.myturbodiesel.com/1000q/egr-system-clogging-TDI.htm ....

Mar4ix

ardle1 wrote: »

Any joy... I think I know off a guy who might have ECU(USED) and very good price..... http://stores.ebay.ie/car4parts?_trksid=p2047675.l2563..... also some interesting sites http://forums.tdiclub.com/showthread.php?t=346842 ... http://www.myturbodiesel.com/1000q/egr-system-clogging-TDI.htm ....

Thanks.

I have replaced vacuum valves (both - turbo and egr ones) , pressure sensor, wich is at the back of engine sitting on air pipe.... no luck. Was talking with some guys, nobody seen those ecu fecked. , box, where ecu sits, is sealed not cracked, dont think there was water in it, i did hard ecu reset by joining plus and minus leads for while... still no luck .

Vacuum lines are connected as per diagram and sound.

I've thinking about , maybe somebody altered shaft which goes from turbo actuator, to control veins , as there is good boost after 2.5 k revs, but slow as fyck till there.... so maybe, somebody made it longer to make car more economical ... i have no idea.

In nearest days, ill pop in in one garage, where they have tools to have a look on ecu maps, and check electric pulses from ecu to solenoids.

ECU goin to be replaced as last thing, when ill get definitive answer that its gone.

Got another youke (passat) in which i fell in love

130 (maybe even + ) hp, 6 speed gearbox .... scary to drive .. :pac: even wont think about oul one

ardle1

Do you know which outlet goes to Turbo Actuator on my N75... Just checking in case somebody swapped by mistake!!

This is actually my N18.. Is it bottom on left?

Mar4ix

ardle1 wrote: »

Do you know which outlet goes to Turbo Actuator on my N75... Just checking in case somebody swapped by mistake!!

This is actually my N18.. Is it bottom on left?

Yes, botom left one, same wich goes to egr on n18 , i have diagramm posted earlear on found in one forum, i have connected as per that diagramm, was visiting that garage, what i told earlear on, they blamed nozzle on vacuum pump, it was loose, else they said vnt at fault ( we assume that all pipes are sound and vacuum valves are working), i have glued that nozzle, no luck,

Tomorrow i will connect vacuum pipe from vacuum pump to turbo actuator. If that thing wont go, then vnt to fault.

Edit:

dont know about vacuum pump. on idling, it have same figures what properly working passat has. would it fail while revving up ? if so, where it getting power then after 2.5k revs ? me thinks it is not vacuum pump.

ardle1

Mar4ix wrote: »

Yes, botom left one, same wich goes to egr on n18 , i have diagramm posted earlear on found in one forum, i have connected as per that diagramm, was visiting that garage, what i told earlear on, they blamed nozzle on vacuum pump, it was loose, else they said vnt at fault ( we assume that all pipes are sound and vacuum valves are working), i have glued that nozzle, no luck,

Tomorrow i will connect vacuum pipe from vacuum pump to turbo actuator. If that thing wont go, then vnt to fault.

Edit:

dont know about vacuum pump. on idling, it have same figures what properly working passat has. would it fail while revving up ? if so, where it getting power then after 2.5k revs ? me thinks it is not vacuum pump.

Turbo usually kicks in at 2.5k revs... So probably means N75 solenoid is activating Turbo Actuator, so N75 is good, I'm not sure but that's what it sounds like!!
P.S is this the diagram you used?

Mar4ix

ardle1 wrote: »

Turbo usually kicks in at 2.5k revs... So probably means N75 solenoid is activating Turbo Actuator, so N75 is good, I'm not sure but that's what it sounds like!!
P.S is this the diagram you used?

Yes, that one, in page 1 have same.

You sure turbo have to kick in in 2.5 k revs? My friends passat has same 101 hp, but it pulls like an airplain compare with mine, and his turbo kicks in about 1.5 k or even earlear revs., a specially my passat has 15 inch wheels and he has 18 inch., so mine should be pretty nippy with his power.

Mar4ix

Does anyone know , or could check with vacuum tester, is vacuum pump should hold vacuum when engine is switched off ?

EDIT:

ok, question narrowed , does brake vacuum box should hold vacuum while engine off ??

Mar4ix

Ok peeps. Found the problem and power now is back in car. Anti shudder solenoid was at fault. it was robbing my vacuum from whole system
I have blocked that vacuum line, and car back on rocket speeds

see picture

ardle1

Well done Mar4ix, great picture, what did you use to plug or block off hose?