SmokeEater2
TYF Newbie
- Joined
- Jun 3, 2012
- Posts
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I'm fresh out of ideas on what to try to resolve this knock I have in my 2000 Tahoe 5.3L w/ 58,000 miles. As far as I know, everything is dead stock with no mods.
It seems to knock on hard acceleration and also when I pick up the throttle after "coasting" at high way speeds. If I keep the same throttle position, the knock will quiet down until I provide additional throttle. I do not get knock if I'm in neutral (ran up to 2,000 RPM).
No MIL or codes. No problems starting and smooth at idle. Minor piston slap for first 30-45 seconds on cold start.
Here's what I've tried:
- Replace both knock sensors w/ AC Delco 213-3521
- Replace knock sensor harness w/ Dorman 917033
- Replace intake gaskets w/ AC Delco (teal colored) & new intake bolts
- Replace fuel filter w/ AC Delco ACP GF652
- Replace EGR Valve w/ AC Delco 214-1080 & AC Delco gasket
- Replace spark plugs w/ AC Delco 41-110 Factory gapped
- Replace PCV valve w/ Purolator Part # PV1063
I have Seafoamed it using 1/3 can into brake booster, 1/3 can into fuel. I have run 3 bottles of Techron (two 10oz on full tank with Sunoco 87 & one 10oz with 10 gallons of Shell V-Power 93).
Changed oil to Mobil 1 with PureOne filter. Small amount of minor particles on drain plug magnet. There was a small sliver of metal in oil filter, but I'm pretty sure it came from the oil filter case when I cut it open.
Smoke tested it looking for vacuum leaks. Fixed mis-seated air intake on throttle body that was leaking.
As you can see, I've spent a small fortune on parts and time, so I'm looking for some advise.
Attached are picts of the original plugs - they look good to me, but I'm not an expert plug reader.
I've also included an OBDII log using a OBDLink SX 2.0 by ScanTool. Timing advance seems way too advanced to me. Not sure what else could be causing it.
Help!!
It seems to knock on hard acceleration and also when I pick up the throttle after "coasting" at high way speeds. If I keep the same throttle position, the knock will quiet down until I provide additional throttle. I do not get knock if I'm in neutral (ran up to 2,000 RPM).
No MIL or codes. No problems starting and smooth at idle. Minor piston slap for first 30-45 seconds on cold start.
Here's what I've tried:
- Replace both knock sensors w/ AC Delco 213-3521
- Replace knock sensor harness w/ Dorman 917033
- Replace intake gaskets w/ AC Delco (teal colored) & new intake bolts
- Replace fuel filter w/ AC Delco ACP GF652
- Replace EGR Valve w/ AC Delco 214-1080 & AC Delco gasket
- Replace spark plugs w/ AC Delco 41-110 Factory gapped
- Replace PCV valve w/ Purolator Part # PV1063
I have Seafoamed it using 1/3 can into brake booster, 1/3 can into fuel. I have run 3 bottles of Techron (two 10oz on full tank with Sunoco 87 & one 10oz with 10 gallons of Shell V-Power 93).
Changed oil to Mobil 1 with PureOne filter. Small amount of minor particles on drain plug magnet. There was a small sliver of metal in oil filter, but I'm pretty sure it came from the oil filter case when I cut it open.
Smoke tested it looking for vacuum leaks. Fixed mis-seated air intake on throttle body that was leaking.
As you can see, I've spent a small fortune on parts and time, so I'm looking for some advise.
Attached are picts of the original plugs - they look good to me, but I'm not an expert plug reader.
I've also included an OBDII log using a OBDLink SX 2.0 by ScanTool. Timing advance seems way too advanced to me. Not sure what else could be causing it.
Help!!