Log In | Register
Skip to main content
Topic: Thoughts on knock sensor (Read 181 times) previous topic - next topic
0 Members and 3 Guests are viewing this topic.
Thoughts on knock sensor
As I continue my search for an LD. I have found one I am interested in. So far you all have been a great help so I thought I would come to you once again.

The owner of the LD I am interested in has the following to say. "It has a knock sensor code that my service man says is not critical at this point as there are no observed symptoms. A $30 part with a $550 labor charge."

Honestly I googled knock sensor and it seems to have something to do with the engine. But I really know nothing about engines or vehicle  mechanics. Should I ran away? The LD is a 1997 with 112,000 miles.

Thanks in advance for your input and thoughts.

Melissa
Melissa
Re: Thoughts on knock sensor
Reply #1 –
Melissa

I don't know what state the LD is located in but here in California, the seller is responsible to obtain a smog certificate.
With a knock sensor code, it will not pass until fixed.
I suggest not buying any LD that the owner does not have or will not obtain the smog certificate.
You could get stuck with a more expensive repair than what you are being told.

And yes, the knock sensor is an important part of the engine management system. It detects knock or preignition and then adjusts the timing to eliminate it.
Here is a photo of what it looks like. This one suffered rat damage and needed it's wires replaced.
Knock detector and its chewed wire | lw5315us | Flickr

Not sure why the installation is so high, it shouldn't take more than a half hour to replace it

Larry
Larry
2003 23.5' Front Lounge, since new.  Previously 1983 22' Front Lounge.
Tow vehicles  2020 Jeep Wrangler Rubicon, 2001 Jeep Cherokee
Photo Collection: Lazy Daze
Re: Thoughts on knock sensor
Reply #2 –
Get the RV professionally checked if you can.  If for some reason you are not doing that take the trick to a Ford dealer and pay for the engine code to be read and get an estimate on the fix.  Note the dealers estimate may be more expensive than a independent mechanic, but the numbers should be in the same ball park. 
What concerns me is what if the code, an O2 sensor for example, is part of a larger problem.
Currently: 2008 36' Tiffin Open Road
Previously: 2007 Mid Bath
Re: Thoughts on knock sensor
Reply #3 –
Thank you! I have contacted someone in the area to inspect it. Just waiting to hear back.
Melissa
Re: Thoughts on knock sensor
Reply #4 –
It could be a easy fix...but one of the wires is hard to get to under the intake plenum which can make it more difficult.  I met someone a couple of weeks ago that had the same code on there V10 due to a rat eating the wire and needed the whole intake removed to repair it.  They had the spark plugs changed at that point since everything was apart.  Blownoutsparkplugs.com showed me how easy it is to damage the front sensor when changing the spark plugs.
1997 TK