Camshaft and Crankshaft Sensors--I'M BACK

torq. verses weight verses rpm
i'm not saying that is the cause but that one code makes me wonder and i have repalced 3 flex plates in the last year for the same kind of complaints
and it's one thing that can easy checked with the right tools

 

more than likely

 

no go for it

 

OK, here's an update. A few weeks ago I did a more thorough cleaning
of the throttle body area. I also tossed a can of Sea Foam in the gas
tank. Wife reported no drivability problems--there was no one time
jerk with the Check Engine Light flashing on--until yesterday when she
said it jerked once at highway speed (she didn't notice if light came
on or not).

Today I went to a Chrysler dealer and got a copy of service bulletin
18-34-98. It accurately describes our problem. I'm stunned that the
solution is to disconnect and REMOVE AND DISCARD the knock sensor. Not
replace, but remove and discard.

If the wife reports the engine jerking problem again, I will
disconnect the knock sensor and have her drive it to see if the
problem goes away. However, seems to me I will have another problem,
namely the potential for pinging and a constantly lit up Check Engine
Light. Won't the loss of the knock sensor cause drivability problems,
pinging, loss of gas mileage, etc., esp. in Minnesota with its wide
temperature swings? Why don't they recommend replacing the knock
sensor?

 

Just disconnect the damn thing and quit worrying about it.

 

Amen, and if you hear pinging buy a higher grade of fuel. Older knock
sensors are notorious for starting to be "fooled" by normal engine
noises as the engine gets some wear on it (wirst pin rattle, piston
slap, etc.) and will cause the engine power to surge as the sensor
fiddles around with the ignition timing trying to eliminate a knock that
isn't really a knock at all.

Disconnecting it will do exactly the opposite of everything you
mentioned, exceot for pinging. Gas mileage will be better, driveability
will be better. The downside is that depending on the enigne, you may
have to buy a higher grade of fuel especially in hot weather.

 

Sorry, I'm too analytical for that <g>

 

Thank you. This is the type of information I'm looking for to try to
solve this mysterious problem. When the problem occurs it occurs at
about the same time/distance in my wife's drive to work. So it would
seem to be temperature related. What could the knock sensor be hearing
at the point the engine finally gets fully warmed up that tricks it
into sending a signal to the PCM?

Again, thanks for the info. Based on your response I can only conclude
that the knock sensor is on vehicles so they can run the engines on
the lowest quality fuel. Otherwise, they are what is known as a "whee"
part, you know, you take it off the vehicle, throw it over your
shoulder and exclaim "WHEE!!" making everything better.

 

OK, here's an update. A few weeks ago I did a more thorough cleaning
of the throttle body area. I also tossed a can of Sea Foam in the gas
tank. Wife reported no drivability problems--there was no one time
jerk with the Check Engine Light flashing on--until yesterday when she
said it jerked once at highway speed (she didn't notice if light came
on or not).

Today I went to a Chrysler dealer and got a copy of service bulletin
18-34-98. It accurately describes our problem. I'm stunned that the
solution is to disconnect and REMOVE AND DISCARD the knock sensor. Not
replace, but remove and discard.

If the wife reports the engine jerking problem again, I will
disconnect the knock sensor and have her drive it to see if the
problem goes away. However, seems to me I will have another problem,
namely the potential for pinging and a constantly lit up Check Engine
Light. Won't the loss of the knock sensor cause drivability problems,
pinging, loss of gas mileage, etc., esp. in Minnesota with its wide
temperature swings? Why don't they recommend replacing the knock
sensor?[/QUOTE]

Obviously the knock sensor function is flawed and there is no fix.
Just use the correct fuel and you should be OK.

 

It appears to be as you say. Now I'm wondering how long Chrysler has
been putting useless parts on their engines? In other words, did they
continue using this same knock sensor set-up for subsequent years?

 

Analytical and anal are not the same thing.

 

Interesting that anal is the root word for analytical though, is it
not? <g>

 

No, newer ones are much better. Its not so much the sensor as the signal
processing that follows it to separate unrelated engine noises from real
detonation sounds. Newer signal processing, for example, eliminates
sounds that occur at crankshaft positions that couldn't possibly be due
to detonation. There's a lot more to it than that, but I don't know what
all else they do.