what is engine knocking mean

Asked by Jul 05, 2013 at 08:37 PM about the 2006 Nissan Altima 2.5 S

Question type: Maintenance & Repair

engine knocking when stopping and turning car off

5 Answers

When stopping...keeps running is a phenomenon called "dieseling" which means that the combustion chamber is running hot and the fuel supply isn't being shut-off when the key is turned off~ might be a stuck relay...see what the trouble codes tell us~

1 of 1 people found this helpful.

I kind of puzzled your complaint and instantly thought "detonation", which is real bad and usually occurs when you've got an out-of-position distributor OR the engine was put together wrong~....but thankfully is just dieseling~....whew.

26,145

Just to supplement what the Judge said....From Wikipedia : Knocking (also called knock, detonation, spark knock, pinging or pinking) in spark-ignition internal combustion engines occurs when combustion of the air/fuel mixture in the cylinder starts off correctly in response to ignition by the spark plug, but one or more pockets of air/fuel mixture explode outside the envelope of the normal combustion front. The fuel-air charge is meant to be ignited by the spark plug only, and at a precise time in the piston's stroke cycle. Knock occurs when the peak of the combustion process no longer occurs at the optimum moment for the four-stroke cycle. The shock wave creates the characteristic metallic "pinging" sound, and cylinder pressure increases dramatically. Effects of engine knocking range from inconsequential to completely destructive. Detonation can be prevented by any or all of the following techniques: the use of a fuel with high octane rating, which increases the combustion temperature of the fuel and reduces the proclivity to detonate; enriching the air-fuel ratio which alters the chemical reactions during combustion, reduces the combustion temperature and increases the margin above detonation; reducing peak cylinder pressure by decreasing the engine revolutions (e.g., shifting to a higher gear, there is also evidence that knock occurs more easily at high rpm than low regardless of other factors); decreasing the manifold pressure by reducing the throttle opening, boost pressure or reducing the load on the engine.

4 of 4 people found this helpful.
255

There's a recall by Nissan to fix this very problem. It has to do with the Engine Control Valve. Call your Nissan Dealer for details, and they will set you up.

4 of 4 people found this helpful.

@ Robert- yeah they'll set you up alright. To get robbed

Your Answer

Add photo

Related Questions

  • what is engine knocking mean 5 answers

    engine knocking when stopping and turning car off

    2006 Nissan Altima 2.5 S

    -

    Maintenance & Repair

  • Knocking at the top of my engine 2 answers

    I'm not sure what is wrong with my 2002 nissan altima.. Went to crank my car and the engine sounded like it was knocking and it sputtered.. The car struggle to stay crunk as long as I got my foot on...

    2002 Nissan Altima 3.5 SE

    -

    Maintenance & Repair

  • What is this? 3 answers

    I just bought my 09 2.5SL Altima a couple weeks ago. My middle dash speaker didn't work so I followed the wire and it lead beneath the left dash speaker so I looked under the steering wheel (Like I li...

    2009 Nissan Altima 2.5 SL

    -

    Maintenance & Repair

  • Knocking noise. 2 answers

    I have a 2005 Nissan altima and I have had hell with this car. It made a loud rattling / knocking noise when driving and gets louder when I hit the gas and settles down a bit when I release the gas...

    2005 Nissan Altima 2.5 S

    -

    Maintenance & Repair

  • Car ran out of transmission fluid. What does this mean? 1 answer

    I have a 2002 Nissan Altima. I noticed a burning smell about a week ago one day when I got out of my car but I assumed it was my brakes because I need them done really bad. However, yesterday I ...

    2002 Nissan Altima 3.5 SE

    -

    Maintenance & Repair

Altima

Looking for a Used Altima in your area?

CarGurus has 74,433 nationwide Altima listings starting at $1,000.

ZIP:

Search Nissan Altima Questions

Nissan Altima Experts

#1 Tom Demyan
Tom Demyan
Reputation 2,100
#2 Cassie Sapphire
Cassie Sapphire
Reputation 680
#3 putolile
putolile
Reputation 650
View All

Related Models For Sale

Used Nissan Maxima
332 Great Deals out of 24,098 listings starting at $1,999
Used Honda Accord
1,049 Great Deals out of 66,932 listings starting at $1,000
Used Toyota Camry
1,225 Great Deals out of 82,694 listings starting at $750
Used Honda Civic
830 Great Deals out of 83,705 listings starting at $750
Used Nissan Sentra
614 Great Deals out of 52,055 listings starting at $1,000
Used Hyundai Sonata
872 Great Deals out of 47,743 listings starting at $1,195
Used Toyota Corolla
1,002 Great Deals out of 68,557 listings starting at $1,800
Used Chevrolet Malibu
1,102 Great Deals out of 79,830 listings starting at $2,500
Used Kia Optima
546 Great Deals out of 28,618 listings starting at $1,750
Used Ford Fusion
1,260 Great Deals out of 76,082 listings starting at $1,500
Used Dodge Charger
535 Great Deals out of 28,457 listings starting at $2,500
Used Chevrolet Impala
545 Great Deals out of 35,509 listings starting at $899
Used Hyundai Elantra
646 Great Deals out of 41,981 listings starting at $900

Used Cars For Sale

2017 Nissan Altima 2.5 S For Sale
8 Great Deals out of 12,349 listings starting at $13,499
2016 Nissan Altima 2.5 S For Sale
105 Great Deals out of 3,447 listings starting at $10,895
2015 Nissan Altima 2.5 S For Sale
180 Great Deals out of 4,713 listings starting at $6,999
2014 Nissan Altima 2.5 S For Sale
163 Great Deals out of 2,939 listings starting at $4,200
2013 Nissan Altima 2.5 S For Sale
36 Great Deals out of 1,237 listings starting at $3,500

Content submitted by Users is not endorsed by CarGurus, does not express the opinions of CarGurus, and should not be considered reviewed, screened, or approved by CarGurus. Please refer to CarGurus Terms of Use.