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Engine Specific Info and Questions => TDI Engine -General Info => Topic started by: SR Heer on December 01, 2012, 07:41:14 pm

Title: ALH compression check
Post by: SR Heer on December 01, 2012, 07:41:14 pm
I am getting ready to do a compression check on my 2000 Golf - TDI - it runs great but I just want to check it now that it has close to 200K miles and see how well it reads as well as use as a reference for later -

So no just what is acceptable like 400 too 500 PSI as long as the different cylinders' readings are within - is it 10 or 15% of each other?

I also would like to ask those of you out there - what are some of your Mk4 TDI or maybe Mk3 TDI readings checked and at what milages?
Thanks for your time and responses!
Title: Re: ALH compression check
Post by: the caveman on December 02, 2012, 07:12:24 am
When I checked into this a few years ago when looking for another AHU, I was surprised to find a much lower tolerance spec than what was for IDI diesels. An AHU [probably the same for ALH] can have compression as low as 270 lbs  as opposed to something like 350 for an indirect injection. Of course I'm not sure how one with run with such low compression but... I guess because these engines start out with lower static compression than the older ones. They still have to be within 15% of each other
Title: Re: ALH compression check
Post by: burn_your_money on December 02, 2012, 08:28:10 am
My friend just bought a 1Z with 5xx xxx kms on it. The engine has around 480 in each hole.
Title: Re: ALH compression check
Post by: bbob203 on December 02, 2012, 08:34:31 am
Quote from: burn_your_money on December 02, 2012, 08:28:10 am
My friend just bought a 1Z with 5xx xxx kms on it. The engine has around 480 in each hole.

Lets hope im this lucky
Title: Re: ALH compression check
Post by: SR Heer on December 02, 2012, 11:23:55 am
how many times does one bump it to get a final reading - 5 or 10 or? what do you all use as a rule of thumb?
Title: Re: ALH compression check
Post by: 8v-of-fury on December 02, 2012, 01:05:28 pm
When the gauge settles out is the final reading.
Title: Re: ALH compression check
Post by: burn_your_money on December 02, 2012, 02:34:10 pm
Quote from: 8v-of-fury on December 02, 2012, 01:05:28 pm
When the gauge settles out is the final reading.

Exactly. Usually around 10 bumps from what I've seen.