if someone could post a pic of this knock sensor that would be great, I've had pinging for some time now tried different brands, different octanes, put fuel injector cleaner and fuel system treatment thru 2 tanks on the dealers advice and still have the pinging, dealer says its normal, i want to try this sensor if its only $18...is the exact term "knock sensor" or will i get the deer in the headlights look when i ask at the parts counter.

 

It's listed in the repair manual as the "knock sensor".
If you want to really confuse them call it the "piezoelectric crystal transducer".

Good luck

 

i get the same noise..dealership says its nothing...i dont believe them. makes me want to trade it away sometimes...so many fuckin issues

 

called one of the guys at the service dept, and left a message on his direct line..told him i had them check out a noise not long ago that i heard, like a rattle can sound coming from the engine..they thought it was a heatshield..told him that im sure its pinging and that im concerned..im due for service next week and i told him i want it looked ASAP. its only 2k-3k RPM's, i dont take it on the highway much, and i rarely go above 3k rpms at all..find it kind of sluggish on the highway..maybe it does have carbon build up..i just want to make sure im covered at the dealer. checked the spark plug i could get to myself and it was perfect..was thinking that would show carbon. jeep is pissing me off lately.

 

Ditto all around. I could reliably make it ping while cruising on the highway in 4th or 5th (with 33" and 3.21) and gently pressing the gas pedal. Usually happened at around 2300 rpm (and slightly higher, maybe 2700 rpm, when I switched from 33's to 32's). Had to have the windows up and radio off to hear it well -- it was pretty faint, but definitely there.

Local dealer told me he didn't have the sensor in stock but that there were like 1,200 on order somewhere, I gather from some regional supplier... makes me wonder if this is a known problem and they're gearing up to replace sensors all over the place. Just a theory, don't take it as truth. I don't want to start rumors.

Anyway, it was pissing me off too, and that's when I decided to take care of it myself. I checked the air cleaner element - no problems. I didn't pull plugs because 1) some are hard to get to, and 2) I was about to try the sensor replacement which I thought was more likely to solve the problem.

Have you tried a different brand of gas? My jeep seems to be happy with Shell 87. I was using Mobil 93 before, then Mobil 87, but switched to Shell 87 at nearly the same time I replaced the sensor. No more pings, and not exactly sure what was responsible for it. My money's on the sensor though.

 

i was using irving 87, switched to mobil 87 and still have the ping..i bet its the sensor after hearing that..i can't wait to hear what my dealer says about it..it just sucks to take off at a good clip from a light or a stop, and hear your engine sound like a rattle can. for 30k you'd expect better...makes me want a hemi!!!!!!!!!

 

talked to the dealer today..they said its possible its just carbon buildup, and recommended i use a fuel system cleaner..highway was too busy to get it really high in the RPM's..but i added a full container of STP fuel system cleaner to a nearly full tank of gas..so by the end of the tank ill know if it helped or not. due for an oil change next week so we'll see what happens.

EDIT: i know people have been told to do this by the dealer before, but i did it just to satisfy them, and if i go in next week with a ping/knock, they'll know i tried

 

Ideally you'd add it to empty tank then fill it, just to mix it up a bit, but that's fine -- see what happens by the empty. Mine didn't show any change until almost the end of the tank if not half a fillup later, but again keep in mind I had several changes at once so it's hard to tell what change had the most effect. In any case, it's worth trying -- if you see no change you've eliminated a variable, and you have more information when you take it to the dealer.

Good luck, hope it works.

 

well i know the techron needs an empty tank..the STP says to use on a tank thats at least half full so im thinking of trying techron on empty if this doesnt work..last night i had a really long on ramp in front of me with no traffic, and i got it up to 4,500K rpm..even after doing that, i couldnt hear the pinging on the way home..i doubt its the STP stuff already but who knows..i did a lot of driving last night.

 

That's good news. I found it often didn't take high RPMs to induce pinging -- even at 2300 or so, just a gentle load (accelerating, but not punching it) up an onramp was enough, or while on the highway and going up a very very slight, long incline. Hope it keeps working for you.