Camshaft and Crankshaft Sensors?

I'll try to give the short story version. 1997 Dodge Grand Caravan 3.8
liter

Was getting a code 54, the code for camshaft position sensor. Autozone
tested and confirmed this. Bought and installed new camshaft position
sensor. On first test drive, within a block or so, got a bucking and
jerking with backfiring. I figured it was the paper spacer on the end
of the sensor wearing off. Got the car home, let it idle to warm up and
another test drive. Everything working great. Drove the car for 50 some
miles last night, ran great, in fact seemed to have more pep than
usual.

This morning the wife drove the car to kid's school (a little over a
mile) and got jerking and hesitating. Service Engine Light came on. On
the way back got jerking for about two blocks then smoothed out and ran
normal. Now I get a code 11. Most curious.

Code 11: 11 No ignition reference signal detected during cranking (bad
Hall effect) OR timing belt skipped one or more teeth; OR loss of
either camshaft or crankshaft position sensor. Can cause the engine to
stop working entirely with no limp-home mode.

I'm figuring it's not the cam sensor, doubtful it's the timing
belt skipped since it ran smooth last night. That leaves no ignition
reference signal or crankshaft sensor.

Any ideas? Is there a way to test for these problems before I start
buying more parts?

 

You need to check for OBD11 codes.
Could be a bad bad new sensor or you replaced the wrong one.
The crankshaft sensor is the one that uses the spacer dot.

 

Here's what I've found for 96-97 Caravans

Code 11-Intermittent loss of either camshaft or crankshaft position
sensors.

Code 11-Crankshaft position sensor target windows have too much
variation.

Code 11-No crank reference signal detected during engine cranking.

So this is all wrong? (fig. 3) This is exactly what the part I bought
looked like and identically matched the part I removed:

http://autozone.com/servlet/UiBroke..._us/0900823d/80/1a/40/69/0900823d801a4069.jsp

 

Did you not read what I told you on the last post???

Glenn

 

Yes, but I must be in denial.

Looks like I'll be replacing the crankshaft sensor too.

 

Ok but even that doesn't guarantee a fix until a scan tool is used to
monitor the problem. It could be a PCM or even wire harness problems. The
other sensor is cheap and easy to install. Go for it!!!

Glenn

 

find a shop that has a bore scope and have them inspect the flywheel/flex
plate without removing trans and see if the flex plate is cracked and
separated
a bore scope can see up there and you won't have to pay the price of
r&r'ing trans to be sure that is not the issue

 

Yep, you're right. I went ahead and replaced the crank position sensor.
No joy. The still car bucks and jerks and now I have a code 43.

Code
43 Peak primary coil current not achieved with max dwell time
OR
43 Cylinder misfire
OR
43 Problem in power module to logic module interface

I also noticed something strange--the Service Engine Now light and the
Cruise Control light were blinking while the car was misfiring.

Any help would be greatly appreciated.

 

when was the last time this vehicle had a tune up with a good set of plug
wires? And how many miles are on it?

Glenn

 

62,000 miles. We got it with 19,000 miles on it. Have never replaced
plugs or plug wires.

More info: I drove it around the block again and it ran smoothly,
normally. I disconnected the battery for five minutes to clear the
codes and once again drove it around the block and this time got
jerking and bucking again, though not as bad as the first drive after
crank sensor install. Service Engine light has not come on (yet).

 

CODE 11 does not say which one.
You need the OBD11 codes to find the right one.
And like said knowing auto zone could even be a bad new sensor.:rofl:

 

I would be willing to bet all you need is a tune up to eliminate this
problem. replacing the plugs and wires. But once again, a good scan tool
would confirm that!!!

Glenn

 

I'm going to have it scoped out on Monday, even if my next repair
attempt is successful.

I'm going to pull the crank sensor out and see if the paper spacer is
missing. I'm thinking that maybe I didn't get the sensor seated in
there far enough and it's giving unreliable signals to the PCM. My
reasoning is the Cruise light coming on and off when the engine
sputters. The Cruise Control uses the crank position sensor to sense
engine speed, correct? The paper spacer seemed to be about .010" thick.
I've got lots of card stock laying around so if it's missing I'll make
a spacer and glue it on and try to install the crank sensor again.

 

The paper spacer was still on the end of the crank sensor, just
slightly pushed off-center and overhanging the edge. I used my thumb to
push it back in the center of the end of the sensor and reinstalled it
pressing the sensor into the flywheel housing while tightening the
bolt. (I had done this previously but this time was more ambitious, but
it's hard to get leverage in such an awkward position.)

Test drive started out promising then began sputtering and backfiring
again. This time the Service Engine Light came on. I've now got a code
11 again. I'll pull the sensor again tomorrow and check for the
presence of the paper spacer. Maybe this time I'll pull the battery out
so I can get more leverage when reinstalling.

 

You can not go by cycling the key to retrieve fault codes on this year
vehicle. It is not accurate!! use a scan tool to retrieve the correct code

GLENN

 

Yes, I intend to have it scanned on Monday.....assuming I can get it to
the shop!

 

Indicating that the sensor was installed to the correct depth.

I'm not sure whether you're trying to fix your van or simply chew
up the crank sensor.
Your problem lies elsewhere...

Get the trouble codes read as Glen suggested.

 

like you said a good scantool is needed here before parts are thrown at it

 

Here's an update:

Finally got it into a shop for hookup to a good scan tool. This was a
shop recommended by a good mechanic friend of mine that I trust.
Indeed, there was wall filled with ASE certificates and they advertise
themselves as "engine drivability specialists" and "advanced engine
performance" specialists.

Here's what they found:

When initially started from cold condition, the car runs for about 10
minutes then stumbles and dies. Starts right up, runs for a minute or
so and stumbles and dies. There are no stored trouble codes, no new
codes are being generated. He agreed that the two main culprits had
been identified--cam and crank sensors. It's not the plugs or the plug
wires. If it was a cracked flex plate you'd likely hear something,
didn't rule it out, but considered it a long shot. The guy basically
said he was stumped, suggesting that perhaps a reflashing of the PCM
might do it, but that he didn't have the equipment to do it. He
suggested I take it to a dealer.

Opinions?

 

Nope, not a reflash problem. If this person had a good scan tool he would be
able to monitor the inputs and outputs of all sensors while the problem was
happening, if they didn't see anything on the scan tool the next thing would
be to do a fuel pressure test.
Sounds to me like they didn't want to get involved in the problem and want
to blow it off to the dealer.
My opinion