1.8T Gurus Help Please

[kujiwara]

Hey guys, my friend just bought an 02 1.8t jetta, awp 180hp version and it idles a bit rough and does not have very good acceleration compared to a normal 1.8t. Car sounds mechanically good, not a single rattle or knock in the engine bay what so ever. And NO CEL on the dash.
I scanned it with my ross tech cable came back with the following:

16486 - Mass air flow sensor G70
P0102 -35-00 -Signal too low

17748 - Camshaft position sensor (G40) / Engine Speed Sensor (G28)
P1340 -35-00 - Incor. Correlation

I'll try unplugging the maf asap but i don't think it'll have that much effect, what I'm kinda confused is the second code, I'm assuming when one of those sensors go wrong it'll trigger that code, but how to i test which sensor is bad? Have you guys experienced these codes before?

[All_Euro]

Re: 1.8T Gurus Help Please

Was the timing belt just done?... cam out a tooth maybe.

[kujiwara]

Re: 1.8T Gurus Help Please

Was the timing belt just done?... cam out a tooth maybe.

the previous owner said the timing belt water pump was replaced a year or two ago, but he's an old man so we were telling him the car didn't run that smooth but he wouldn't listen he just kept insisting there was no CEL. On the 1.8t to check the timing do i just pull the timing cover and look for a cam mark and a timing mark on the flywheel?

[All_Euro]

Re: 1.8T Gurus Help Please

Ah... well, it’s prob best to go through things pretty thoroughly then. TDC marks are under the timing cover and down at the crank damper - kind of a pain to check. When you’re at TDC you can also pull the valve cover to check the cams.

I’d start by unplugging the MAF and working your way through the sensors, etc... easiest to hardest approach. Here’s a link to a Ross-tech page - should be more info there too if you dig around...

http://wiki.ross-tech.com/wiki/index...dit&oldid=4850

[Natty54]

Re: 1.8T Gurus Help Please

Its possible the codes are old or are soft.

[kujiwara]

Re: 1.8T Gurus Help Please

Ah... well, it’s prob best to go through things pretty thoroughly then. TDC marks are under the timing cover and down at the crank damper - kind of a pain to check. When you’re at TDC you can also pull the valve cover to check the cams.

I’d start by unplugging the MAF and working your way through the sensors, etc... easiest to hardest approach. Here’s a link to a Ross-tech page - should be more info there too if you dig around...

http://wiki.ross-tech.com/wiki/index...dit&oldid=4850

Thanks I'll try to those procedures as soon as i can

Its possible the codes are old or are soft.

I see, ill clear them first and see what happens then

[kujiwara]

Re: 1.8T Gurus Help Please

I checked maf looks like it's bad, unplugging and plugging makes no difference, vcds reads 0g/s, fuse looks good will check if there's power going to it, if power good buying new maf. Is there a way to check the timing belt with vcds?

[BolideVW]

Re: 1.8T Gurus Help Please

Yeah sounds like a bad maf. Not sure about the vcds, don't think so.

Next time you pull it apart or do the timing, mark the crank cover marking with bright coloured nail polish, and do the same on the crank pulley marking. Makes it so you can see with everything still together.

[sabbySC]

Re: 1.8T Gurus Help Please

If you don't have receipts for the timing belt change,I would assume that it hasn't been done.

[kujiwara]

Re: 1.8T Gurus Help Please

still didn't have time to jack the car up to check, but i did get a chance to pop the timing cover off the top and feel the belt tension by the cam, the belt tension on the non tensioner side is kinda soft, like quite a bit softer than a self tensioned accessory belt. I'm leaning towards changing the timing belt