Knock sensor plug came off sensor, truck also doesnt start

robbyb20

Well-known member
Oct 2, 2019
146
16
Seattle
So this was fun, at gas station filling up and went to restart the truck and no start. No sounds, battery tests good (12.6v), lights dont dimm, fuses checked, etc. Go to take a mallet to the starter to see if its stuck and notice a wire (not power to starter) hanging down with the plug still on it as well as the connector to a sensor but no sensor. Plug has ERR5594 and see that its the knock sensor.

The sensor is falling apart in place and i have ordered a new sensor to replace it with. Truck was towed to my neighborhood.

Question is, will this cause the car to not start including no sounds at all from starter? No codes showing up on ultragauge or obd2 reader.

Thoughts?
 

Toran

Well-known member
Feb 3, 2017
349
31
Ohio
I broke my knock sensor off while replacing the starter over the Summer. The truck still ran with the sensor removed. Long story short my issue was similar to your. My issue turned out to be an ignition switch issue. I was able to put a momentary switch on the starter and the battery and the truck started every time provided the key was in the start position.

The truck has two knock sensors.
 

robbyb20

Well-known member
Oct 2, 2019
146
16
Seattle
I broke my knock sensor off while replacing the starter over the Summer. The truck still ran with the sensor removed. Long story short my issue was similar to your. My issue turned out to be an ignition switch issue. I was able to put a momentary switch on the starter and the battery and the truck started every time provided the key was in the start position.

The truck has two knock sensors.
Thats what I was reading about the sensor but secretly hoping it would somehow to be different for mine. Ooof,

Guess Ill replace and sensor anyways and keep looking. Ill check out if your fix will help me as well. Did you find a permenant solution yet or still using the workaround?
 

Toran

Well-known member
Feb 3, 2017
349
31
Ohio
I am still using the workaround.

A few years ago I did the ignition mod because my key would sometimes stick in the ignition, it was like trying to pull excalibur from the stone! The mod worked for years until just like you I was at a gas station returning to the truck and it didn't even make a click when trying to start. After another attempt it worked. This would happen a few more times before it just quit. I thought it was the starter and replaced it but still no start. Than I thought it was the knock sensor since I bumped it during the starter install and cracked the brittle plastic so now it was just dangling.

Be careful not to cross thread the knock sensor when you put it in. Do a finger tightening first, than snug it up with your tool.
 

robbyb20

Well-known member
Oct 2, 2019
146
16
Seattle
I am still using the workaround.

A few years ago I did the ignition mod because my key would sometimes stick in the ignition, it was like trying to pull excalibur from the stone! The mod worked for years until just like you I was at a gas station returning to the truck and it didn't even make a click when trying to start. After another attempt it worked. This would happen a few more times before it just quit. I thought it was the starter and replaced it but still no start. Than I thought it was the knock sensor since I bumped it during the starter install and cracked the brittle plastic so now it was just dangling.

Be careful not to cross thread the knock sensor when you put it in. Do a finger tightening first, than snug it up with your tool.
So, just wanted to dot my I's and cross my T's, i went back out to see if any codes popped and also see what would happen when its cooled down and the damn thing started. Its sounding more like youre dilema because I could not get it to start again. The difference is its now turning over but barely like it wants to die.

Any reason you havent replaced the ignition switch? They are stupid expensive it looks like any other reason? I also have had some difficuties removing my keys at points.
 

Toran

Well-known member
Feb 3, 2017
349
31
Ohio
I was in a pinch and needed to get the truck up and running. I have the manual 5 speed version so the ignition switch replacement isn't as expensive, though money is money.
I just used what I had at the time. I wired the momentary switch and mounted it inside the truck. These days I turn the key to the 2nd position and press the button, the truck starts every time.
 

robbyb20

Well-known member
Oct 2, 2019
146
16
Seattle
I was in a pinch and needed to get the truck up and running. I have the manual 5 speed version so the ignition switch replacement isn't as expensive, though money is money.
I just used what I had at the time. I wired the momentary switch and mounted it inside the truck. These days I turn the key to the 2nd position and press the button, the truck starts every time.
When this first appeared, would you hear the starter turn over at first and then slow down/eventually die and not turn over at all or would it not turn over at all from teh get go?
 

Toran

Well-known member
Feb 3, 2017
349
31
Ohio
I would hear nothing from the starter or engine. I would sometimes hear a clicking from a relay located in the passenger footwell.
 

robbyb20

Well-known member
Oct 2, 2019
146
16
Seattle
Just went out and checked it again. Wouldnt start but would slightly turn the first time and then a little less the second and finally no sounds. The relays on the passenger side are activating with each turn. Ill still check voltage to charger just in case. but just for my piece of mind, im going to swap with a new starter since the one I installed this summer was used and my hit rate with previously owned (non-refurbished) items has been pretty abysmal.
 

Toran

Well-known member
Feb 3, 2017
349
31
Ohio
If you get any spare time take a peek inside the starter you are removing. It is really easy to rebuild them with either new brushes, or solenoid.

If its not the starter, you have to roll out the ignition wire that connects to the starter. If it’s the wire than you can trace it down and replace it. And if the issue is the ignition switch than you know the sound of a cash register opening. Or say hello to a $15.00 momentary switch that you can discreetly mount anywhere inside the truck.
 

robbyb20

Well-known member
Oct 2, 2019
146
16
Seattle
If you get any spare time take a peek inside the starter you are removing. It is really easy to rebuild them with either new brushes, or solenoid.

If its not the starter, you have to roll out the ignition wire that connects to the starter. If it’s the wire than you can trace it down and replace it. And if the issue is the ignition switch than you know the sound of a cash register opening. Or say hello to a $15.00 momentary switch that you can discreetly mount anywhere inside the truck.
Thats the plan! Going over the write up from the post this summer that had the instuctions on it. It will at least be nice to have a spare.
 

robbyb20

Well-known member
Oct 2, 2019
146
16
Seattle
I got mine at the same place. Talked to the guy on the phone, said to call with any questions. Seemed like a good place.
 

Toran

Well-known member
Feb 3, 2017
349
31
Ohio
I only communicated via email and his response was prompt. Lifetime warranty on the starter.