Q: Excessive vibration at idle 2002 VW Jetta

asked by on January 27, 2017

Very rough vibration at idle. Engine does not miss and but stays steady at 800 rpm - but engine vibration is shaking entire car. Runs well at speed, pulls strong - no misfires or bogging under load. Oil looks good. Fuel pressure is good at 35-38 psi at idle. Used multiple bottles of fuel system cleaner to date. Cleaned MAF. Recently replaced downstream O2 sensor, plugs, wires, coil pack. Replaced crank position sensor 6 months ago. Replaced all motor mounts 12 months ago. Not sure what to do next: check compression, replace injectors, replace fuel pressure regulator, replace MAF, check for vacuum leak (how)? I don't want to throw money at random parts.

Car starts right up, pulls strong. Getting ~24 mpg (which is lower than it should be).

My car has 123000 miles.
My car has a manual transmission.

Car idle is rough Inspection $79.99 - $89.99 Get a Quote

Hi - I suspect your rough idling is an air leak (loose hose or crack in the air intake), or dirty idle air control valve. A leaking exhaust gas recirculation (EGR) valve would also cause rough idling. I recommend a rough engine idle inspection performed by a mobile, professional mechanic, such as one from YourMechanic, who will come to your location, diagnose this problem, give you an accurate assessment of damage and cost estimate for repairs.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

What others are asking

Is the solenoid malfunctioning or the camshaft with a P0011 Check engine code?

Code P0011 is most commonly caused by the solenoid or cam sensor. I would recommend replacing the solenoid first and then cam sensor.

What does ECP and ECM mean and is it bad?

Hello. I suspect you mean EPC (not ECP), which stands for electronic pedal control or electronic "gas pedal linkage". There is no longer a physical cable, wire or lever between the gas pedal, and the throttle body on the engine...

Throttle body needs aligning.

Yes, on your vehicle the throttle body does require a relearn procedure after replacement. You do indeed need the factory scan tool, or a scan tool with factory capabilities. Have the experts at YourMechanic a call, they have a wide...

If i upgrade my car's thermostat to a better brand/higher quality will that make my heater blower hotter air?

Hi there. You can change your thermostat to the cold weather thermostat if your vehicle is equipped with the stock or warm weather thermostat. For your vehicle, there is a thermostat for the temperature rating of 180 degrees fahrenheit for...

Running really rough, not starting usually. Battery light came on. Car overheated. Headlights turn off when I put the high beams on.

Hi there. With the information given, it sounds like you accidentally put 3 bottles of Gas Heet (water / antifreeze remover) into the gas tank. There is to be only 1 bottle of Gas Heet to a full fuel tank...

how do you relearn a new throttle body

Throttle body alignment (calibration of the position of the throttle plate) on your vehicle requires an automotive scan tool to access the electrical controls for the throttle and the automatic calibration routine. To get an idea of what is involved...

Brakes making a grinding noise after car is in reverse. And put it in drive brakes grind for about 2 car lenghts then a thud

It sounds like the caliper brackets may have been misaligned when replaced. Some brake calipers are designed to "float" meaning they will slide along a small path to allow for movement in the wheels when changing gears or shifting movement...

Engine is overheating and heater has stopped working

If the engine was replaced and the AC refrigerant system was drained then the system should be put under a vacuum for a minimum of 30 minutes to ensure all moisture is boiled out and then leak tested to ensure...

How hard is it to replace the EGR valve on my 2000 Ford Focus

Hi there. If the bolts to the EGR (exhaust gas recirculation) valve are frozen in place by rust, you could put a small blow torch to the bolts and get them cherry red and then try to remove them. If...

Related articles

Industry News for Automotive Techs: October 1-7
Wireless electric car charging, VW diesel scandal payouts, 3D-printed car technology, new Cardone car parts, and high September auto sales.
The Best Used Cars to Buy If You Need to Haul a Motocross Bike
Of Of course you would love to be able to ride your motocross bike everywhere, but the reality is, at some point you're going to need to transport it. A cargo van of almost any make or model would be...
A Buyer’s Guide to the 2012 Volkswagen Jetta SportWagen
The The station wagon is making a big comeback with American car buyers. While SUVs are still popular, we’ve seen a lot more sales of compact SUVs, crossover utility vehicles, and sport wagons lately. Among those, the 2012 Volkwagen Jetta...