My 2003 i35 has a "stumble" or "hiccup" at idle. Other than that, the car runs fine.


The mechanic says the timing chain is loose and I'm running on borrowed time. He suggests rebuilding the engine or replacing the car.


what do you think? Is he pulling my chain, or on the money?

 

What your car needs is another mechanic, not an engine.

There are a lot of causes for the stumbling, but the timing chain is not one of them.

The timing chain tensioner pads do wear and are designed to be replaced. The chain itself rarely needs to be replaced. If you had timing chain was loose, you would hear a rattle at startup and idle.

 

^agreed. Your mechanic is trying to take you for a ride and run up a big bill. It's time to replace him!

 

That was my thought as well. What could be causing the hiccups at idle?

 

A few common reasons are vacuum leak(s), worn out/bad spark plugs

 

How many miles does your car have? The vq is one of the best engines and even at 200000 shouldn't have to replace it al song as normal maintenance is done . Spark plugs are a big cause if this see if you have the car fax when all the major engine work has been done. Mine has 100000 miles and still runs like a dream ( then again I baby it)

 

some possible causes:
-bad gas
-spark plugs
-clogged injectors
-coils
-MAF

in no particular order

 

Car has 185,000 miles and plugs were just changed (by the same mechanic).


Could it be the wrong plugs?