Hi All - back again and need some advice
I was trying to troubleshoot a warm/hot engine starting issue so been poking around the forum to research. Long story short, I plugged in reader for diagnostic and received a confirmed P0331 Knocking Sensor Bank 2 issue (code below from reader. No CEL so was a bit surprised. I'll take a look at it some more this weekend but wanted to get some input before I jump to conclusion of getting new sensor.

Some additional info:
1. regarding the starting problem when hot/warm - after driving around and parking car and having to restart after sitting for 15-45 mins, starter turns but engine doesn't turn over. Under the same condition but if I turn the key to position 2 and wait a couple seconds to let fuel pump work, it usually starts find. There are intermittent problems it with idling at only about 500RPM and engine wants to stall, a couple revs tend to resolve the issue. Fuel pump and filter replaced this past year.
2. I've also notice gas mileage has taken a dump of recent and going up some of the high passes in Colorado, flooring the pedal does absolutely nothing, I mean it doesn't down shift and no engine rev...this is normally at 50+ so maybe it's just age knowing how slow these cars are.

There could be multiple issues here but I wanted to tackle he know sensor first.

The below I took a snapshot with my Android app at idle after driving around...so not sure why it shows me going at 74mph, I know the speed sensor is correct when driving but the fuel trim numbers don't look right to me.

Any help would greatly be appreciated.

'98 D1 with 160k

Confirmed Trouble Codes
-P0331: Knock Sensor 2 Circuit Range/Performance (Bank 2) (Powertrain, Generic)

Pending Trouble Codes
-none

Permanent Trouble Codes
-none

Freeze Frame
-P0331: Knock Sensor 2 Circuit Range/Performance (Bank 2) (Powertrain, Generic)
-Fuel system status: Fuel system 1: Closed loop (1)
-Fuel system status: Fuel system 2: Closed loop (1)
-Calculated engine load: 47.8 %
-Engine Coolant Temperature: 192 °F
-Short Term Fuel Trim - Bank 1: 1.6 %
-Long Term Fuel Trim - Bank 1: -19.5 %
-Short Term Fuel Trim - Bank 2: 7.0 %
-Long Term Fuel Trim - Bank 2: -19.5 %
-Engine RPM: 2835 RPM
-Vehicle Speed Sensor: 74 mph

 

Duh....didn't know that the freeze frame I posted above was only captured by the app when it detects the fault.

I went ahead and cleared codes to try and mimic problem again.

 

What grade fuel are you using? Know how to perform a compression check? IACV - is it clean? Spark plugs - what type and brand. Last time wires changed, plugs changed? Checked for arcing wires? CkPS and CPS wiring and connectors? O2's changed/original?

Need more info than what the app brings with it.........

 

Fuel - usually use regular in Colorado that's 87 or 85 in past few years, use to run premium and still do but not consistently.
IACV - replaced last year
TB - Cleaned
Spark Plugs - replaced last year, champion copper
Wires - replaced once, I don't recall but believe it was at 90k or 120 service with standard wires. No arcing
O2 Sensors - originals
Fuel pump and filters replaced last year
CPS/CKPS - haven't tested, never been replaced...
Don't know how to perform a compression check

 

The 02's are long overdue if original. Run a tank of premium if and when you can and see if the code is still pending towards the end of the tank. Wires on these truck make it about 30k and poop. Check gap on plugs.

 

Thanks for the advice.
Here's what I plan to do:
1. I'll run a tank or two on premium. ( I will go ahead run a bottle of Techron through after that for good measures)
2. Wires are reasonable enough to replace so I'll get that done.
3. O2 Sensors..hmm...looks this will cost me $400+. I am thinking that if the problem does not come back after the above steps, I will probably just leave it alone. Emissions tests still pass well within specs and don't know enough about it right to really make a decision. However, I'll probably spend some time to read through and take any advice.

 

Go to Amazon for the 02's, way cheaper. You really only need to start with the upper two, those do all the heavy work for the GEMS to run efficiently.

The rest sounds like a good plan. I imagine the truck will run smoother than it has been even if it's running well now.

 

From what I understand, the knock sensor creates a small voltage, created by the engine vibration. If working correctly, it will tell the ECU to retard timing when pre-ignition or detonation is detected. The code is telling you to replace it because it is not producing the correct current.
I found O2 sensors to be cheapest on Amazon, and do not buy generic or aftermarket sensors. Also I would only replace the upstream ones, because the downstream only determine if the cats are working properly. I do not see any codes for poor cat performance.
The closed loop you are seeing is more than likely the upstream O2 sensors are not working, since they tell the ECU how much fuel to inject in the engine.

 

Just looked at Amazon and not sure which ones are OEM. Is the manufacture of the OEM sensors Bosch?

Like this one:

 

This is the one I bookmarked from Tom Rowe (antichrist);
P0331 Continuous knock detected, bank B - Cylinder knock correction at maximum value. If one or more cylinders has reached its maximum knock correction value and stays there for a certain time i.e. continuous knock, then a continuous
knock fault is present.