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Mon Sep 05, 2005
18:15
Today's "down": That nice set of Mahle piston rings that I bought quite a few months ago to use in my ABA rebuild turns out to be for 1.8 liter VW engines with an 81.0mm bore. If you know the ABA motor, then you know it's a 2.0 liter with an 82.5mm bore. Had I bothered to look at the label on the bottom of the box after receiving them, then I would have known right away:
wrong rings
Gah!!! I'm a moron.


That was a real downer after I got myself all excited for reassembly and even put together one piston/rod assembly:
note the can of Moxy Rod and piston assembled


Today's "up": I got a chance to try Ross-Tech's little diagnostic procedure to do a sort of crude check of the mass airflow sensor in the black Golf. I think their fuel-trim writeup was geared toward something other than the ABA cars because the measurement block they said to read for the mass airflow sensor feedback was 002. I ended up finding it in 003 instead. So I did what they said - while monitoring the sensor feedback in group 003, I did a run up to redline in 2nd gear. The reading peaked at about 103g/s which is definitely a little high. The calculation is pretty simple: take the peak reading and divide it by 0.8. The result should be the approximate horsepower output of the engine. In my case, it's a stock ABA which is supposed to be 115 horsepower. My peak reading of 103 divided by 0.8 gives 128.75. To reinforce this, I found that there was a DTC stored in the car's computer:
16487 - Mass Air Flow Sensor (G70): Signal too high
  P0103 - 35 - 10 --- intermittent


So that gives me something solid to go on, at least.

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Date: 12/28/06, 20:52:04 PST
From: Omar
Comments: I have a question I took pistons and rods out from my aba to get forged pistons from wiseco now I do not remember the Rod position what I mean by Rod position is where was the groove of the rod baring facing if the wir to the exaust side or the intake side can you please help it would be greatly apreciated thanks in advanced

Date: 12/30/06, 07:06:09 PST
From: max
Comments: Hi Omar, I'm a little unclear on what you mean about the rod bearing grooves facing toward exhaust or intake. If you are wondering what orientation the connecting rods themselves are supposed to be in relation to the engine block, then it doesn't seem to matter according to the Bentley manual. Take a look in your Bentley manual in section 13-6, figure 8. That diagram shows the piston/conrod assembly and points out marks on the rod bearing caps that have to line up with marks on the rods themselves. They say it does not matter which side those marks are on (either toward #1 cyl or #4 cyl). You must take great care to ensure that the bearing caps do not get mixed up, that they stay with the their original rods. Also be careful to make sure the rods and pistons get put back into their original cylinder bores (ie, make sure the rod/piston that came from cylinder 1 go back into cylinder 1, and so on). I may be replacing rod bearings in my wife's ABA engine soon - if I do then I will take pictures and post them up on the blog and hopefully those will help clear up any confusion for you.
A1 parts for sale:
intake air preheater hose
Item: Intake air pre-heat hose (from exhaust manifold shroud to air box), for Scirocco 2 (1982+)
Condition: New
$12


A2 parts for sale:
A2 GTI dual round grill, with inner lights
Item: GTI dual-round grille with inner lights, bulbs, and lower trim strip
Condition: Used, lower trim strip is weathered.
$35

parcel shelf strap
Item: Parcel shelf strap, 3 available
Condition: New
$3.50 ea.

A2 valve guides, 8 valve
Item: 8 (eight) valve guides, German, standard size, for 8 valve head
Condition: New
$24

wheel cylinder
Item: Wheel cylinder (for rear drums, obviously), 2 available.
Condition: New
$12 ea.


A3 parts for sale:
parcel shelf strap
Item: Parcel shelf strap, 3 available
Condition: New
$3.50 ea.


A4 parts for sale:
ALH water pump
Item: OEM Water pump, ALH engines
Condition: Used, 130,000 miles
$20