Improve Nexus 4 Vibration Intensity This is basically the same question as posed here: Increase vibrate strength

I thought there might be a different answer for the Nexus 4, however, seeing as how it's a different manufacturer and the OS has changed slightly. 

I came from using a Nexus S which had a really good vibrate. With the Nexus 4, however, even with nothing else in my pocket sometimes I can't feel it. I'm used to being able to get a slight buzz or something if I set my phone down on my desk but with the Nexus 4, the best I can hope for is a slight buzz if it's on a hard surface. Touching papers or something else? Better hope you were looking at the phone, otherwise you're going to miss incoming calls.

For other Nexus 4 owners, is this a noticeable issue with your phone? Maybe mine is slightly defective. If not, is there any way to boost the intensity or strength of the vibration through settings? 

I've seen that the Galaxy phones have a vibration setting that can be adjusted but I can't seem to find something similar on the Nexus 4.
There is an app called Trinity Kernal Toolbox. It helps to adjust Vibartion intensity in Galaxy Nexus and Nexus 4(only).
But the thing is your device should be Rooted. And its a paid App.   

The app supports the following:
- Adjusting of CPU Min/Max Frequencies
- Selecting of CPU Governor
- CPU Governor settings
- Selecting of I/O Scheduler
- Adjusting of Max Screen Off Frequency (Galaxy Nexus only)
- Adjusting of all CPU Voltages
- Sound control: High Performance toggle + Volume boost (Galaxy Nexus only)
- Color control (Galaxy Nexus + Nexus 4 Only)
- Contrast control (Galaxy Nexus Only)
- Adjusting of Vibration Strength (Galaxy Nexus and Nexus 4 only)
- USB Fast Charge Toggle (with plug check)
- Thermal Throttle Toggle (Galaxy Nexus only)
- Smart Reflex Autocomp Toggles (Galaxy Nexus only)
- Wifi PM Toggle (Steadier stream or better battery) (GN + N7 only)
- Menu with utility functions to make common tasks easier.
- Reboot Widgets to access common options from Homescreen
- CPU Temperature Widget (Galaxy Nexus + SGS3 + Nexus 7)
- Statusbar Temperature display on select widgets (GN + SGS3 + Nexus 7)
- Restores trivial settings on boot
- Frequency/Voltage settings restored on boot if chosen
- Crash Recovery (To get you out of boot loops)
- Optimizes system independent from init.d (Great for stock roms)  

May be it will help you to solve your issue. Don't blame me for recommeding a Paid App

If you are interested just flash this Kernal to support it