ALH No Get-Up and Go!

Thanks for your help.
Daughters car - 2000 Golf ALH w/218K miles. I just completed a timing belt change. Verified the injector pump timing (VAG-COM) but didn't need to change it. Timing is half-way between the blue and green lines (slightly advanced). Also verified the fuel pressure @ 3.4.
Car idles fine, sounds good, but doesn't seem to have any get-up-and-go. In talking with daughter she says it has been this way for going on a year.
I changed the MAF sensor 2 months ago for an initial hesitation when accelerating. The new MAF correct that. No CEL. Neighborhood driving seems fine but embarrassingly slow getting on to the freeway. Eventually it will reach 70 MPH. Having driven the car when it was new I would say it has 1/2 the acceleration it used to.
What else should I check?
Thank You,
Randy Graves
CdA, Idaho

Intake manifold clogged almost shut perhaps??
Used to be very common before ULSD fuel, but if it's never been cleaned it probably needs it.
Simple things first. Fuel filter clogged up?
Then start checking turbo operation.

Probably but gotsta ask. Where'd you get the MAF sensor. What brand?

I also recommend checking the intake manifold. It will do exactly as described.

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Check vacuum hose from N75 down to turbo. Seeing several giving up as these cars are ageing. Lotsa heat down in that area.

Clogged intake and egr, if it’s never been cleaned it’s a good idea to do that.

Cheap eBay parts, replace those, if any.

Pull the hose off the turbo, is there any play on the compressor wheel? In and out or side to side?

Sounds like it just needs some regular maintenance to keep it working properly.

My daughter has an 01 Bug , after it had been flashing awhile, a week or so, she says “Dad whats that flashing curly light for”? Glow plug light flashing, fortunately in her case it was just for a brake light.

She’s pretty savvy when it comes to her car but ofttimes when something happens and everything still works enough to get from point A to point B she can ignore what I would consider important.

Thanks You (Everyone) for your Help!

Removing the hose and looking into the EGR/Anti-Shutter valve side of the intake manifold I can see a heavy, heavy, buildup of carbon deposits inside.

Will proceed with cleaning the intake manifold and EGR.

Again Thanks and With Much Appreciation,
Randy Graves

I think your actuator is froze or rusted through (no lower engine cover maybe).
Intakes always look nasty, VW claims a passage the size of a dime is sufficient for operation. I'd say clean it if the passage is anywhere near that small. Clogged intake is a definite possibility.

How did you measure fuel pressure? 3.4 what?

Did you measure appropriate MAP to verify your turbo builds boost?

I've found a plugged fuel filter is the first thing that limits power in this engine, I recently had a filter plug after only 2000 miles or so.

Intakes definitely still clog, even with "ULSD", diesel soot from the EGR mixes with blowby oil and builds up. I just put 100k miles on my ALH, and with periodic EGR use it was still plugged almost 50%. I did NOT notice any appreciable amount of power increase once cleaned, so it's good to do but may not be the issue.

RKGraves said:

Thanks You (Everyone) for your Help!

Removing the hose and looking into the EGR/Anti-Shutter valve side of the intake manifold I can see a heavy, heavy, buildup of carbon deposits inside.

Will proceed with cleaning the intake manifold and EGR.

Again Thanks and With Much Appreciation,
Randy Graves

Click to expand...

Very important to remove the intake and egr to accomplish a good cleaning. You do not want to dislodge a piece of carbon and have it sucked into the cylinder and destroy a valve.


Its a filthy job.

I believe when the OP said 3.4 for fuel pressure he meant injection quantity...

No answer on where the MAF came from.

Could unplug it and see if it runs better.

Cleaning the intake would be way down my list too unless it's really bad.

Yes I agree, it's likely some control and many folks will shop parts by price.
Mitigating is the car is pre-ULSD and depending how it was driven, could be clogged.
Interweb guessing.

Thanks Everyone For Your Help!

Have intake manifold and EGR assembly removed and intake opening is restricted down to about one inch +/-. Will clean and re-assemble.

MAF sensor replaced 2 months ago is a Bosch OE. Daughter noted that with the new MAF sensor her fuel economy returned to 45 mpg.

I appreciate everyone's help - Thank You!

Randy Graves

While you're at it check the air filter and particularly the snowscreen if you haven't.

Update:

Intake & EGR carbon all cleaned out and car runs notably better. I would say the "old girl" is 75% of what I remember, and Daughter is happy.

Unplugged the MAF to see the difference and engine ran rougher at low RPMs but seemed to have more pull over 2,500 rpms.

Broke the vacuum inlet connection on the Anti-Shutter Valve Actuator (darn!). Need to find a replacement.

I Very-Much Appreciate Everyone's Help - Thank You!

Randy Graves

Glad you’ve solved the problem, quick work by the way.

Still sounds like part of the issue is a bad MAF is you have better power with it disconnected.
Did you remove the EGR and intake manifold for the cleaning?

Yes Sir, I did remove the EGR & intake manifold for a thorough cleaning. I was expecting this to make more of a difference as intake was restricted down to apx 1 inch. Car has been in the family since new and it had never been done (218K miles).

Installed this MAF in April:
Bosch Original Equipment 0281002757 Mass Air Flow Sensor (MAF) (from Amazon)

Thinking I should next replace the vacuum lines.

Short of ordering another MAF anything else?

Randy Graves

The vacuum lines are always suspect if they have not been replaced in the immediate past. Do you have a vacuum gauge to check all of the connections under the hood? Sometimes the old solenoids develop cracks and cause a loss of vacuum, causing a loss in power. I went through this myself with cracked solenoids losing vacuum causing a great loss of boost/power.

Update #2:

Was going back over everything and found a vacuum line disconnected. The one end of this line attaches to the same distribution point as the turbo. Reconnected it and 'The Ole Girl' has the caffeine back in her coffee! Not perfect but 90%+ of the get-up-and-go I remember.

Many of the vacuum lines are showing age. Will plan for a future date to test with a vacuum gauge and replace lines/parts as needed.

Thanks Again Everyone For Your Help! You inspire me to look for ways I can do the same for others.

Best Regards,
Randy Graves
CdA, Idaho

Probably not a factor in your case, but the vanes in the turbo can carbon up, and that will reduce your boost. It has to get pretty bad for a P1550 code to get issued, but by then the total power is substantially compromised.

I have a 99.5 and a 2003 which get this problem. Wife and daughters car don't. I drive like a old grandmother, which is part of the problem.