bad Knox sensor?
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bad Knox sensor?
Has anyone had a pinging problem with their 5.3L flex fuel? mine pings when you just drive down the street under normal accel and gets worse when you give it a little gas... not mash on pedal just increase slightly to say.. speed up to make a yellow light. thanks guys!
#2
If it was a knock sensor then you should be getting a service engine soon light or something of that nature. If not then it might be a lifter going bad or a crank bearing. Has the pinging been getting louder as time progressed? Since the pinging started, has it gradually been getting louder from week to week? Have you lost oil pressure? How many miles does your 5.3L have? Is it more of a knock or a ping?
The knock sensors had a poor design on the 5.3L a while back which let water and debris sit in a hole with the knock sensor and thus caused accelerated corrosion. If you do need to replace it I would recommend getting some high temp. gasket maker and seal the top of the rubber fitting that is suppose to seal the knock sensor within the valley cover. This had happened to my '02 Z71 Tahoe.
The knock sensors had a poor design on the 5.3L a while back which let water and debris sit in a hole with the knock sensor and thus caused accelerated corrosion. If you do need to replace it I would recommend getting some high temp. gasket maker and seal the top of the rubber fitting that is suppose to seal the knock sensor within the valley cover. This had happened to my '02 Z71 Tahoe.
Last edited by cam3439; January 13th, 2010 at 5:24 PM.
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Thanks for the help. it seems to be ok these days. i had a hypertech program installed and it pinged big time with that install so i uninstalled it and it still had some residual programming in the computer and has since relearned to be normal. i called hyper and they told me that it would stop pinging and i should install the newer hand held programmer. i think not.. i am very disapointed in GM as a whole. the truck is an 07 and the steering wheel paint is coming off, the paint is coming off the a/c controls, the nav is a joke... gives wrong directions, and the elec seat adjust motor is making noises. no wonder they needed bailout money! POS is my thoughts. Going to buy FORD next time... much better made vehicle.
#4
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Usually when you put in a programming chip you also have to change out the thermostat and use premium fuel for knocking or pinging issues associated with different performance settings the chip provides....
Its a fine balance of performance to efficiency and all have a cost...
Its a fine balance of performance to efficiency and all have a cost...
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Thanks buddy. i changed thermo, added air raid cold air box w/ intake tube and some other minor tweeks. i was running high octane AND added octane booster and it didnt help. Pinged like crazy so i just took it out... to be honest it really didnt make that big of a difference for what it cost.
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opening up the exhaust with headers and a freeer flowing muffler with your mods can increase the top end power but it won't do much for daily driving.
I would also double check and make sure they sent you the right mod chip if you were getting that much pinging. The lower temp thermo and high octane fuel should have reduced the knocking and pinging.
I would also double check and make sure they sent you the right mod chip if you were getting that much pinging. The lower temp thermo and high octane fuel should have reduced the knocking and pinging.
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i agree a create motor would be cool... but i just wanted to ramp up what i have and not spend a ton of money. i upgraded the exhaust and that helped a little. for a while i was running e85 as it was 75 cents cheaper than gas. now it is only 7 cents cheaper so i never use it. at the time of install i thot i had run all the e85 out, maybe i didnt. it didnt ping until a couple months after the install. when it started to ping i called hyper and they said it may have still had ethanol in the system when i installed it so computer made adjustments accordingly thinking it was high octane. since i removed program it does not ping anymore... well at least now it doesnt. it pinged when i removed the program for a couple months.. and i mean pinged like crazy. now.. it is fine. done messing with it. i think i will go get me a older jeep cherokee and build that up... with a create.
#9
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Yeah the E85 is a bad mix for performance, it may be cheaper but it is also less efficient and lacks the octane punch that gasoline has....
The E85 may have been your problem all along, as the engine has to adapt to the E85 and learns to use it so to speak and I would bet the power chip was not designed for E85 and was doing its best to accommodate for it.
The E85 may have been your problem all along, as the engine has to adapt to the E85 and learns to use it so to speak and I would bet the power chip was not designed for E85 and was doing its best to accommodate for it.
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yup.. exactly.. funny thing is when i installed the chip it ran fine. never pinged and ran ok. after a while (say maybe 6 months) it started to ping and was progressively getting worse. i would put octane booster, one time 2 bottles and it still pinged... so i called hyper they gave me a long disertation as to why they think it was doing that but ultimately they had no idea. no biggie tho... it really didnt make that big a diff except in shifting. i like a firm shift so i may try to program the trans only w/ a kit...