# Intake changeover valve issue



## GRN6IX (Jan 2, 2003)

Upon startup (& constantly afterward), my changeover valve pulses as if it's trying to open (or close, not sure). It makes a nasty clicking sound that can be heard from in the car.

I also have a bad hesitation that matches the pulsation above 4500 & no power down low, as if the valve is still moving.

Bad valve or bad solenoid?


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## apstguy (Apr 3, 2006)

It could be either, do you have a hand vacuum pump to test it? You might just have a vac leak in one of the hoses but getting to them is going to suck.


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## GRN6IX (Jan 2, 2003)

I definitely have a vacuum leak. When I get in the car after it sits overnight, I have a really hard brake pedal until I start the car.

All the freaking vacuum lines are under the damn manifold in this car...


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## apstguy (Apr 3, 2006)

Lucky there are not many vac lines at all. Two solenoids under the manifold, one to the FPR, one to the changeover valve, one to the SAI valve, and the one to the EVAP system. Most are easily accessible, under the manifold not so much. If it makes you feel any better it is pretty easy to loosen the bumper support to see the lines. *Edit* See ""putting the lock carrier in service position".


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## GRN6IX (Jan 2, 2003)

Awesome info! I planned to do this next week & that will be great help. :beer: for you :thumbup:


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## apstguy (Apr 3, 2006)

This should help you more, took me a bit to figure this all out when I had a vac leak so I might as well share. 








5 is the SAI valve, 24 is the change-over valve, 25 is the SAI solenoid, 26 is a vac reservoir, 27 is a check valve.

Here are my L33T drawing skillz:








Vac lines on the left are for the EVAP system, and are most likely not your issue. Grey rectangle is the EVAP solenoid, orange box is the quick connects to the rear EVAP system.
Right side: Yellow circle is the SAI valve (under manifold). Purple line runs to the SAI solenoid. Huge red rectangle is the vac reservoir. Purple rectangle is the change-over valve and connected to it is the change-over valve solenoid. Red circle is the fuel pressure regulator. 

Hope that helps!


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## GRN6IX (Jan 2, 2003)

Still fighting with my changeover valve. At present, I've replace everything that has to do with it, including:

Valve,
both solenoids,
ALL vacuum lines,
intake shift rod,
Rod bushings,
check valve

The change-over doesn't happen when it's supposed to at 4500rpm, but the engine bucks & hesitates at or after 4500rpm, almost as if the valve is stuck & trying to open.

It does appear to be difficult to move by hand, even after the rod & bushing swap.

A scan with VAG-COM shows no codes, but I still have a hard brake pedal after the car sits for a while, indicating a vacuum leak of some sort. I can't seem to pinpoint this leak & I'm out of ideas.

Would a vacuum leak cause a malfunction with the change-over (the valve itself doesn't leak)? Could a bad kombi-valve on the SAI system be the cause (leaking vacuum into the head, or during change-over)? I suggest this because there are two solenoids linked together (per the above diagram).

I'm unable to enjoy the top end of this motor & I am seriously out of patience & money for this problem.

Help!


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## apstguy (Apr 3, 2006)

I'm wondering if the vac canister has a leak in the plastic somewhere. Only way to check it it to use a hand held vac and see if it loses pressure after a while.


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## GRN6IX (Jan 2, 2003)

I just picked up a vacuum pump, I'll have to test that out


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## GTIVRon (Jul 24, 2009)

Component cleaner has usually helped me find my vacuum leaks. 

I start the car and and spray down the hoses 1 section at a time, if idle picks up I know I found it. Is there a way to get a spray nozzle down under the manifold spray up the res.?


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## MachtSchnell (Oct 31, 2010)

Have you had any luck finding out where the problem was?
If you have fixed it, how bad was getting to all that stuff?


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## stylngle2003 (Oct 2, 2004)

hard brake pedal screams low system vacuum to me. check that reservoir!


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## D03GLIR (Oct 21, 2004)

*Any other ways to check vacuum to the crossover valve?*

Not looking to jack the thread but have a similar issue.
Thought I'd found a vac/ boost leak @ the drivers side crossover rod bushing so ordered a kit and replaced. Took over a 1/2 hr to get the actuator out, mostly disconnecting the white vac fitting below item 2 in your figure.
Put everything back together, rod rotates OK, actuator worked w/ vac from mouth, white fitting made a "click" when attached but I get no crossover action.
It was working when I took it apart.
Other than the obvious of disassemble and measure vacuum on line, any quicker ways to diagnose and fix this?
Getting that part out it a bi##h since my SC charge pipe is 1/2" to the right of the actuator and it is also a bear to remove. I really don't want to have to go to the "lock carrier" position to get at stuff.
Any issue leaving it alone until spring when it warms up? I know I'll lose some power up top but no codes?

Thanks...


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## jlsgli89-03 (Aug 25, 2003)

spammer!


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## GRN6IX (Jan 2, 2003)

stylngle2003 said:


> hard brake pedal screams low system vacuum to me. check that reservoir!



Reservoir is at maximum, I believe it may be the check valve from the intake to the brake booster. I've found an OEM replacement for $140 (!!), but I'm wondering if I can just buy a check valve (http://www.mcmaster.com/#check-valves/=aeyvmh) & some rubber hose. 

Any ideas on what sort of check valve I should buy?


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## GRN6IX (Jan 2, 2003)

Bump for ideas please...


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## MachtSchnell (Oct 31, 2010)

Waiting for some warm weather to see if I can pinpoint where my issue is coming from. I'll let you know what I come up with.

Good Luck!:beer:
B.


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## GRN6IX (Jan 2, 2003)

Thanks! I found the issue, but couldn't find the thread. It was the booster hose with the check valve coming from the back of the intake manifold. Apparently the check valve was bad. $40 later, no vac leak!
Part number: 1J0-612-041-FL


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## apstguy (Apr 3, 2006)

Glad you found it, those vac leaks are a pain!


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## MachtSchnell (Oct 31, 2010)

So, replacing the bad check valve solved your change over issues?
I still haven't gotten around to fiddling with the car, but it has very similar symptoms your car was having. 

May I ask where you picked up the part#1J0-612-041-FL from for 40 bucks? 
My search results from Google are in the $50-$60 range.:sly:

Thanks!:beer:
B.


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## GRN6IX (Jan 2, 2003)

https://www.1stvwparts.com/partscat.html 

Do a part number search from their OEM catalog. They're in WA so shipping is a bit slow to the east coast, but worth the wait IMO


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## MachtSchnell (Oct 31, 2010)

Thanks!


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## Huguito 502 (Dec 27, 2015)

*03 gti vr6 24v cutting off @4200 rpms and now wont start*

Hi Team; here's my issue. My car started to cut off power at 4000 rpms and the epc light started coming on. then I left it parked in my garage over Christmas and I tried to start it. I came on and quickly turned off. now it wont start at all. it turns but wont fire..can you please help me. I'm in 3rd world Guatemala city and have spent lots of cash in different mechanic shops , and no one seems to be able to get it started. here are the codes from the numerous obd2 scans that we have performed:
P1425 Tank Ventilation Valve Short To Ground 

P1435 Secondary Air Injection Pump Relay Circuit Short To Ground 

P1421 Secondary Air Injection Valve Circuit Short To Ground 

P1118 O2S Sensor Heater Circuit Open Bank 1 Sensor 2 

P1516 Intake Manifold Changeover Valve Circuit Open


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## Eric D (Feb 16, 1999)

Huguito 502 said:


> I'm in 3rd world *Guatemala* city and have spent lots of cash in different mechanic shops , and no one seems to be able to get it started. here are the codes from the numerous obd2 scans that we have performed:
> P1425 Tank Ventilation Valve Short To Ground
> 
> P1435 Secondary Air Injection Pump Relay Circuit Short To Ground
> ...



Have you tried taking the car to VW @ Resdenciales Granai y Townson Cinco, Guatemala City, Guatemala?

Surely they have the correct diagnostic tools to find your issue. Stop wasting time at the local taller who may not even specialize in VWs. 
If you can't afford or are willing to go to a dealer, find a local VW club with members that wrench professionally. Hopefully one of them works for the dealer or a well equipped modern repair shop, not some run of the mill cualquiera.

Can you tell us what the various shops did for you? What parts were inspected and replaced if any?
Did the shops actually do any "real" troubleshooting to the wiring? Does the shop have a VW break out box or a Power Probe with ECT2000? The Power Probe with wireless transmitter and receiver will quickly find faults in the wiring.
It will pin point the exact location in the harness without the need of removing components. The old way of troubleshooting with a DVOM or break out box will require you to cut the harness as you guess where the problem lies.


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