Question about 1999 GMC Yukon

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99 Yukon 5.7 110k always maintained. Lower engine knock that is sporadic. Getting worse

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I may be wrong on this but I had the exact same vehicle come into my shop.Same issue.
It was not a lower end knock although it sounded as if it was.A catalytic converter breaking apart. they have issues with them.

Posted on Aug 14, 2009

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Posted on Jan 02, 2017

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99 olds.intruge 3.5 engine

loud knocking internal lower part of engine usually means [ rod knock ] --bad wrist pin -spun bearing -or piston ring]s] --that the worst other can be timing failure --or component failure --you need to isolate the noise and diagnose from there

Oct 01, 2016 | Cars & Trucks

1 Answer

Steering knock has developed when turning either L or R help ?

those are 99% CV joints.

also check tie-rods and anything that attaches to the hub, but I'm 99% sure its the CV shafts. Find out which side is worse. that the bad shaft.

Jul 05, 2013 | Mercedes-Benz 190-Class Cars & Trucks

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My 2000 yukon knock sensor code came up. the shop said $ 700 to replace. the 5.3 motor runs great. Does this need replacing?

the engine has two knock sensors they are mounted under the intake manifold, $700 sounds a bit high , i think i would price around, as to the question do you have to replace them, NO, but they are there it aid in the ignition control if the engine spark knocks these sensors are there to sense this. and also if one of the sensors is always reading as if the engine is spark knocking then the on-board computer will keep trying to ****** the timing and this will effect you power, and fuel millage.

Mar 22, 2011 | 2000 GMC Yukon XL

1 Answer

I have a 2000 mercury villager runs fine when first started in the morning but after several miles stats bucking and knocking worse when you try to excelorate bogs down real bad, could this be the knock...

do not change the knock sensor.

sounds like cam sensor in distributor is going. works cold fine, then as engine warms upo it starts going. is tach needle jumping too?

Buy reman rich porter on ebay for $200. sensor inside is not serviceable. common issue on 99-00.

go here


Dec 30, 2010 | 1999 Mercury Villager

1 Answer

Engine knocking doesnt need oil

The engines in the Dodges tend to run on the hot side whitch causes sludge to build up in the engine. They also have very small oil passages which sometimes get clogged with sludge. When this happens the rod bearings starve for oil and begin to fail. The knocking starts out light, only detectable at high rpm;s. It gradually gets worse until it reaches a point where you hear it all the time. On some dodges you only hear the knocking after the engine has warmed up. Some say to use oil additives or engine flushes to try and stop the knock. There is no remedy. Once is starts, it will only get worse.If the engine fails and you take it in for warranty, the dealership will find sludge in the motor and say the warranty is no good because you did not maintain the engine and change oil at regular intervals. Dodge is fully aware of the sludge problem and subsequent engine failures in their vehicles. They choose not to address the problem, instead blaming it on the vehicle owners. Good luck. Maybe you will be one the lucky ones that deals with a honest dealership.

Dec 21, 2010 | 2006 Dodge Magnum

2 Answers

How to repalce a knock sensor on my 2004 gmc yukon

Hi welcom to fixya. A defective knock sensor may cause engine detonation or reduced spark advance and fuel economy. When a knock sensor is removed and replaced, the sensor must be tightened to its specified torque. If the knock sensor is installed tighter than it should be, it may become too sensitive and provide an excessively high voltage signal, resulting in more spark ****** than required. When the knock sensor is installed looser than it should be, the knock sensor signal will be lower than normal, resulting in engine detonation.
To replace the knock sensor:
  • Disconnect the knock sensor wiring connector.
  • Then, unscrew the sensor.
  • Remove the knock sensor.
  • Reverse the procedures to install the part.
  • 15 ft.lbs.torque
  • hope this helps.Thank You for using fixya..iluv2fish.. Ray..

Jul 09, 2010 | 2004 GMC Yukon

1 Answer

Knocking noise from rear of car

There are two common known problems with the rear suspension. One problem is the rear spring colliding with the rear lower arm during rebound. This is caused by a lack of support in the rear lower arm and the upper spring seat. The solution is to fit a spring isolator sleeve to prevent the metal to metal knocking. Another common problem is knocking of the top coils of the springs. A revised rear lower arm spring seat has been fitted since 02/2002.


Apr 05, 2009 | 2003 Ford Focus

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