Need Help. 97 1FZ, slight top end knock, no codes even when I disconnect O2 sensors.

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LINUS

LINUS

Waiting for the Great Pumpkin
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Because:
1) of all the things you touched (changed) w/o confirming net plus good between the touches - AND STILL have no CEL on OBDII..."trust the force, Luke." Trust the instrumentation until you have reason to believe otherwise.
………
Refreshing so many things at once - w/o confirmation between - could yeild end results orphaned in a sea of new evidence.
+1 / Bingo.

It’s like old school algebra.

1 variable at a time in this situation so you don’t orphan / double isolate - a problem.
 
J

Jaysjammin

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I was just saying spun rod bearing to give you an idea of the sound and not the location.
Sorry, got lost in a train of thought because I was worried about rod bearings. I'll post a video when I have time.

Because:
1) of all the things you touched (changed) w/o confirming net plus good between the touches - AND STILL have no CEL on OBDII..."trust the force, Luke." Trust the instrumentation until you have reason to believe otherwise.
2) Did you ask PO if he/she/they/it/them/one/we/our/woof changed any ps components prior to your ownership?

Loud pipes cover alot.
Refreshing so many things at once - w/o confirmation between - could yeild end results orphaned in a sea of new evidence.

+1 / Bingo.

It’s like old school algebra.

1 variable at a time in this situation so you don’t orphan / double isolate - a problem.
With no CEL, I'm worried I can't trust the instrumentation. Aside from HG, no real maintenance history.

Valid points that I absolutely agree with, I bought it as a project and I have a daily and another project I "finished" so I got it home and tore it apart. I've spent more money on it than what I bought it for and I fully expected that.

The why:
The truck was in rough shape when I bought it. Original owner 97-07 had head gasket failure, in 07 the mechanic bought it from them. In 2011, it became an off-road only rig. I gave it a decent once over, checked frame, coolant, oil, transmission, locker engagement, modifications and damage. Clean CarFax, stayed in Charlotte its entire life, no accidents. Dent in rocker panel, faded paint, A/C didn't work, front seats needed repair, surface rust and mud underneath and it had a 3 inch body lift.

Things I found doing initial tune up: there was a twig in one of the vacuum modulator lines because the nipple on the modulator had broken off, there was a red pipe from an aerosol can that was JB welded into the top pipe on the radiator because that nipple broke, AC didn't kick on and it was missing 8/24 lug nuts. Given that, I don't think there's been any maintenance aside from oil changes for the last decade.

So the plan was to just go through the whole thing. Radiator was getting replaced so I might as well overhaul the cooling system, thermostat, control valve, clamps and hoses. I don't like how body lifts drive, especially a 3 inch; in order to remove that, I had to cut off the exhaust. With no radiator and no exhaust, I could just sit in the engine bay and work. Radiator is out so I might as well do the oil pump seal and front main, manifold is off so I took apart the oil cooler and added valve, gaskets and O-rings, oil pressure sensor and harness. Did the valve cover gaskets, seals, plugs, wires, distributor cap, rotor, gasket and O-ring, replaced a dozen little vacuum lines. Air filter, rubber intake hose, TB hoses and gasket. Fuel filter, pump, gas cap.

Unrelated: sound deadening, insulation and speakers/Bluetooth. Wire wheeled and painted/primered everything underneath, replaced rear control arms, stabilizer linkages, OME lift, transfer case cross member, Slee skids, Slee stabilizer drop. List goes on.

"could yeild end results orphaned in a sea of new evidence."
:rofl:Beautifully said.

Regarding the knock I'm at belts, exhaust, PS, valves. Before valves, I'll likely remove the intake manifold so I can replace a few vacuum lines I couldn't reach and replace the intake gaskets in case there's an air leak causing the engine to run lean.

I'm all for not having a check engine light staring at me but if it's running lean or incorrectly, I want all of the codes that I can get.

I'll post a video at some point, "knock" is a very generic word for a long list of sounds.
 
S

Samuel642000

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Dfw
I am pretty sure we are experiencing the same problem. My "knock" is coming from around injectors 3/4 and gets louder with RPM's. I've tested without belts, still have a noise. Replaced everything from the valve cover seal up, still have a noise. I have no idea what it is or could be however I am about to change all the injectors and will do some digging while I'm in that area for possible culprits.
 
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Jaysjammin

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I am pretty sure we are experiencing the same problem. My "knock" is coming from around injectors 3/4 and gets louder with RPM's. I've tested without belts, still have a noise. Replaced everything from the valve cover seal up, still have a noise. I have no idea what it is or could be however I am about to change all the injectors and will do some digging while I'm in that area for possible culprits.
I haven't had a chance to check anything yet so let me know how that goes.
 
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Samuel642000

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Dfw
Well got the new injectors in, for the most part. Only bad thing I could find was these injector wires going to #3injector. I would assume this would cause it to short and no telling how long its been this way. But ill let you know tomorrow if there's still a tick/knock when I get it back together.

20211125 235134
 
S

Samuel642000

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Well tick/knock is still there although it does sound a little quieter. But it does run a lot better after new injectors and fuel filter were changed.
 
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Jaysjammin

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Well tick/knock is still there although it does sound a little quieter. But it does run a lot better after new injectors and fuel filter were changed.
That is better than nothing I suppose. What injectors did you go with?
 

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