Autodata 3.48 outlines the following service schedule for the V6 variants:
Service 1 (Minor Service - Every 12 Months or 12k Miles):
Service 2 (Major Service - Every 24 Months or 24k Miles): autodata 348 top
This is where the word “top” becomes actionable. Autodata 348 instructs you to install locking tools to hold the camshafts and crankshaft in the TDC position.
Warning: If you cannot insert the locking pins easily, you are not at true “top.” Do not force the pins. Rotate the engine one full turn (360 degrees) and try again. Remember, TDC occurs twice per four-stroke cycle (once on compression, once on exhaust). You want the compression stroke TDC. Autodata 3
It is important to note that the keyword "Autodata 348 Top" is most relevant to the DVD-based versions from the late 2000s (specifically version 3.48). In modern cloud-based Autodata (the current subscription model), these numerical modules have been replaced by dynamic search and VIN decoding.
However, many independent shops and DIY mechanics still use legacy Autodata DVDs. If you are using an older system, 348 Top remains an active and essential data set. In the latest online version, you would find the same information by searching for "Delphi DCM 3.7 Fuel System" and selecting "Advanced Diagnostics." Service 2 (Major Service - Every 24 Months or 24k Miles):
First, it is essential to clarify what an Autodata reference number represents. Autodata organizes its technical data into unique numbered entries. These entries cover everything from fluid capacities and torque settings to complex ECU pinouts.
Autodata 348 is historically associated with timing belt replacement procedures for specific multi-valve engines, most notably found in European and Asian passenger vehicles. While the exact vehicle application can vary slightly by software version and regional update, the number “348” is most famously linked to 1.4L, 1.6L, and 1.8L 16-valve petrol engines produced by major manufacturers like Vauxhall/Opel, Suzuki, and certain GM platforms during the late 1990s and early 2000s.
The inclusion of the word “top” in the search query “Autodata 348 top” is the most critical aspect of this keyword. It refers to the procedure for setting Top Dead Center (TDC) on cylinder number one. This is the foundational step before any timing belt is removed or installed.