Garage Lube

• NVH Forum
• Tyre Vibration VW Golf 2004
  • A MK5 VW Golf 2.0 TDI with a distinct vibration throughout the cabin at a very specific road speed range of 67- 73 mph, presented a real nuisance at cruising speed. This problem resulted in the customer driving at 65 or 75 mph to avoid the vibration.
• NVH Cabin Vibration Maserati Quattroporte 2010
  • The trouble with vibrations is that we all interpret them differently (which is why we should measure and not guess), but with this vehicle you could not deny a considerable vibration throughout the vehicle in a very specific engine speed range. Starting at 1450 rpm through to 1700 rpm the vibration was evident, with peak vibration occurring around 1600 rpm.
• Finding faulty engine mountings Rover 100 1996
  • My 1996 Rover 100 helped me get to grips with NVH. The first test I did was in the passenger compartment with the accelerometer on the inner seat rail. I was a bit surprised by the magnitude of the engine second-order (E2) peak, but, with no experience to fall back on, I asked Steve Smith at Pico for advice.
• NVH diagnosis of transmission screech Opel Kadett 1991
  • The vehicle had developed a very loud screeching noise, which sounded like a cross between a squealing drive belt and a loose stack of rapidly vibrating metallic plates. The car was powered by the original GM 16SV OHC transverse-mounted petrol engine and the THM125 automatic transmission and had covered a genuine 52k miles from new.

The PicoDiagnostics NVH Kits from Pico Technology are the cost-effective answer to the many NVH problems facing technicians today. The software provides a real-time diagnosis to the technician, in the form of either: a bar graph, a frequency chart, a 3D frequency chart, RPM order, road speed view or a time domain view.

The ability to start the recording before a road test and playback and analyze the recording back in the shop, ensures that the driver's attention remains on the road. Saving the recordings couldn’t be easier: Much like our other automotive software, you can simply save the file to your laptop’s hard drive.

The PicoDiagnostics NVH kits make use of the PicoScope Automotive oscilloscopes and are available in a number of configurations to suit your needs. You can be sure that your investment in the PicoDiagnostics NVH kit will benefit your business without the need for further spending. If you already have a PicoScope Automotive oscilloscope, you’re halfway there.

If you don’t have a PicoScope Automotive oscilloscope, but you wish to use an NVH kit, you can invest in one of our Essentials kits and receive your choice of NVH Diagnostics kit complete with a 4 channel Automotive oscilloscope in a dedicated hard carry case.

Although the NVH Kits are available in different configurations, they differ only in the number of parts supplied. In each case, a BNC cable connects the interface box to your Automotive PicoScope and a USB cable connects your PicoScope to the PC or laptop on which you run the PicoDiagnostics software.>/p>

A separate J2534 Scan tool (see below) or VCI (not supplied) can be used to provide RPM data or an electrical signal that can be used for RPM.

Starter, Standard or Advanced

The Starter NVH Kit will allow you to measure vibrations on 3 axes, (X, Y and Z). The Standard NVH Kit gives you the option to also measure vibration or sound on a single axis at an additional location on the vehicle. The Advanced Kit gives you the option to measure vibration or sound at four different locations on the vehicle. The Starter to Standard Upgrade Kit gives you an extra set of all the kit items.

All Kits are available in a carry case or foam tray. The foam trays enable users to store their NVH Diagnostics Kits safely in a tool chest of their own choosing.

Please note that the NVH Starter Kits (PICO-PQ126/8) do not contain the yellow cable PICO-TA245.

NVH Essentials Kits

If you want to use a Pico NVH Kit but do not own a PicoScope already, you can now purchase an NVH Essentials Kit. These are the equivalent to the basic NVH Kits but with a 4-channel Automotive PicoScope 4425 included.

Customer complaints surrounding noise/vibration are subjective at best and present technicians with a challenge before diagnosis and rectification begins. Applying the NVH kit to the vehicle will allow the technician to road-test the vehicle with the customer to obtain all vibration and noise levels.

Once this valuable data has been collected it can be analyzed and compared to previous captures or against donor vehicles. Often what is perceived by the customer to be a “problem” vibration is in fact a characteristic.

Now you can present and compare objective data with test results from donor vehicles to reassure your customer all is OK. Alternatively, comparing data may highlight a problem within the vehicle allowing the technician to proceed to a repair with confidence supported by measurements taken.

Below are just a few of the typical scenarios where the NVH kit can save time and money:

• Cabin vibrations at speed
• Engine vibrations throughout the entire RPM range
• Clutch judder or vibration
• Transmission and bearing whine
• Auxiliary drive noise
• Brake judder
• Steering vibrations

The root of all NVH problems is a vibration. In some cases these are unwanted or unexpected vibrations, and in other cases they are always present (e.g. engine combustion), but should not be transmitted to the driver/passenger.

Sound is simply a vibration that is transmitted through the air (or other medium), and is heard when it reaches a person's ear. Although the perfect hearing range is 20 Hz to 20 kHz, most of us are more like 100 Hz to 15 kHz at best. Vibrations are usually felt at frequencies below 200 Hz, and in the overlapping frequency range vibrations can be both felt and heard.

In order to deal with this frequency range effectively, the PicoDiagnostics NVH kit contains both microphones (for sound), and accelerometers (for vibrations).

Traditionally, NVH problems have been viewed as difficult to solve. NVH complaints can be subjective as people have different levels of NVH acceptance or feeling. For a technician to tackle these issues effectively they need the right tools and procedures to diagnose complaints in an objective, repeatable and easy manner. The PicoDiagnostics NVH kit does that and also generates customer reports to show that an improvement has been made against their complaint.

Setup Wizard and Software Help

The Pico NVH test has a set of wizards to guide you through the necessary connections and the vehicle data that will generate information and results in a format that is easy to understand.

The system detects vibrations (and sounds) that change (wheel, engine, propshaft etc.) but also fixed frequency vibrations (e.g. electric cooling fan). Results are displayed in a report that is easy to understand and can be viewed in the way that suits you.

Comprehensive help files explain likely causes and solutions, and the functions provided by the software make it easy to diagnose the problems in a logical way to reveal the root cause. The same system will also give you the ability to measure the effectiveness of any repairs or modifications and demonstrate the results to the customer.