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Discussion Starter #1
I could use some advise. I've had the car for two weeks now and it has 126K miles. This is the only TDI that I have ever driven so I can't compair. The car runs great (I think), it will get up through the RPM range quikly ( 2500-3000) during normal shifting but RPM will slow after 3500. After reading this site, I removed/cleaned the EGR and intake, which it needed with only about 1" of passage. After the cleaning there was a big difference in getting up to the RPM but it still slows from 3500 to 4700. Is this normal or do I need to replace the MAF ?
 

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The engine torque levels out but the horsepower should still be climbing. It's hard to say if it's normal because we can't feel how it feels. You can try some of the tests in the MAF FAQ article but I wouldn't replace it for no reason without doing some tests first.
 

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I would bet that its the MAF's fault

In my case the MAF registered to low air flow. This meant that i couldnt rev past 3700-4000 rpm. I also had/have issues with the vnt turbo.

This is a graph of my car with bad MAF and parcally stuck vnt mechanism:

(You can see that MAF actual/specified are way off, and RPM stop on about 3700 rpm.)

How is the response on low rpm? (if you floor it in 1./2. with 1500-2000 rpm)
On my car the response in low rpm was sloppy, but that was because of the sticky vnt mechanism.

I change the MAF to a cheap china copy and now the car revs to 5500+. But the car has issues on idle, so I would recommend to buy original (I will replace the cheap china MAF soon):
www.idparts.com
www.boraparts.com
www.1stvwparts.com
http://www.worldimpex.com
 

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When my neighbours car's maf went it was still able to rev up no problem but was just seriously lacking in power but a new maf soon sorted it out.:)
 

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Discussion Starter #6
Thanks everyone, I'm sure the the MAF has never been replaced. I have a gut feeling I just need to replace the MAF after reading all your responses and the reputation the MAF has. The turbo spool up sounds good and seems to work fine, it will get up and go but just falls on its face at high RPM which I don't hardly go there anyway.

I just got back from a 600 mile round trip and the the car felt great shifting/driving normal and cruising 75mph but when I accelerated to pass I noticed as it picked up speed it would have a slight power loss every 3 second interval. Its not bad, I just know somethings not right.

My 1st priority is the TB change. Parts and tools are on the way. I hope the MAF can wait for another month or so till I get some more bucks. Thanks again.
 

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What is your brand and model? Do you know which turbo you have?

The MAF on my Audi A3 2000 (ALH) had a sticker on it that said when it was produced, but this was on the 'Audi' partnumber-sticker (date was 02/02/00). Could be worth checking before ordering a new one.

If your car is engine code ALH, then the replacement part 038906461C should be used insted of 061A906461. I think amazone.com sells it for 90$ + shipping, and idparts.com sells it for 115$ + shipping.

Cleaning the turbo can be a pain. Bolts and housing are known to rust together, thats why its often reccomended to just try to change the MAF. The replacement prosess is kidsplay when compering it to the turbo cleaning.

Its also recommended to replace the oil feed line (it has a nasty habbit of twisting itself if you dont counter hold it with a 'custom' tool) when you remove the turbo. The oil feed line alone is about 75$ (for ALH engine code on idparts.com).

When you say that:
"accelerated to pass I noticed as it picked up speed it would have a slight power loss every 3 second interval"

This makes me wonder if you just have a vacuumleak, bad N75 valve or a leaking turbo actuator. The ECU controls boost pressure by operating the N75 valve (no vacuum = no boost, full vacuum = full boost).

But again I dont know much about cars. If you have a ALH engine with VNT15 turbo (or another VNT tubo), I think that this might be quite possible.

Good luck
 

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But again I dont know much about cars. If you have a ALH engine with VNT15 turbo (or another VNT tubo), I think that this might be quite possible.
Lol I don't know much about cars, you're pretty good at faking it:D
 

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Usefull help in addition to the site's 1000q

I found these very usefull when I cleaned my turbo:

VNT15 w/ integrated exhaustmanifold
VNT15 wo/ integraded exhaustmanifold

Good luck

offtopic2
I only know about my own car, since Im a cheapo that wont support the stealership. I bought my first car a year ago and have picked up a thing or two since then. Lets just say that im a computer programmer and Google is my friend. google it
 

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Discussion Starter #11
Problem Solved

I stumbled across a thread on Fred's site with simular issues i was having through the RPM range. The solution was called "Cage Fix" simply by unpluging the MAF senser and applying dielectric silicone compound onto terminals of the connector and working it in by unplugging and plugging the connector a couple of times. The only thing i did not do was fill up the entire connector with the stuff as suggested.

Went for a drive and nailed it on the open road, it accelerated through the gears up to 80mph with out the usual surges as descibed above, when I got home I put it in neutral, floored it and it rapped up fast to the red line which it never did before.
 
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