khnitz

I had a "scare" and new behavior when driving home on the highway from a quick errand this morning - the engine seemed to cut out for a moment, the tach showed the RPMs dropping, some of the dash lights flashed and then everything came back running again. This happened while cruising at speed, with no throttle inputs. After this incident, I noticed that the tachometer was "wobbly", constantly varying its reading by +/- 100rpm or so at any engine speed - before this, the tachometer was always steady/accurate throughout acceleration, steady-state cruising, idle, etc. The SES light was lit - but it was already lit for an EVAP leak I need to correct (P0455).

Searching here, and recalling other threads I've read through, I figured the crankshaft or camshaft position sensors were the culprit. I finished the drive home, with the only issues being the jumpy / wobbly / jumping tach, and an occasional stumble from the engine (very occasional, but still unnerving). I read the codes when I got home, and P0335 (Crankshaft Position Sensor) was now a stored code, in addition to the previously expected P0455.

So, my plan is to replace the crankshaft position sensor with the Hitachi part. I checked with the previous (he's also the original) owner (a co-worker of mine), and since the Z has 130k on it and he never replaced any of the sensors, I also ordered the Hitachi parts for both camshaft position sensors and will replace those at the same time.

I'll share my post-repair results next week, once the parts arrive and I can install them. Oh, and an additional detail on the vehicle is that it is all stock. Stock exhaust, intake, etc. with no mods. There are a number of threads in here related to the crankshaft position sensor, but a lot of them have to do with sorting things after clutch, intake, or other engine mods.

As for the P0455, I just resolved an EVAP leak with the same code on my kids' 2003 Dodge Intrepid. That code was tripped when I broke a fitting in the vent system of the gas tank, and then tried to repair it. I replaced the damaged fitting, and used some hose to replace the OE interconnect, but that only improved the error to a P0456 (minor leak) from the P0455 (major leak). The final thing was to go in and use gasket sealer at the fittings of where the replacement hose connected, and then that EVAP leak error cleared. So, I'll have to look over the EVAP system on my Z and see where I have a leak. I already replaced the fuel cap gasket, but that did not resolve the issue.

khnitz

The new Hitachi sensors arrived on Saturday, and I got the time to install them today. All in all, it's not a difficult job. Here are my tips for the next person researching this repair:

• The crankshaft position sensor (I used Hitachi CPS0006) is located behind the splash shield that mounts to the front underbody brace. Remove that splash shield, and the sensor is right there. The connector is easy enough to remove - push down on the tab and separate the connector from the sensor.
• The right bank camshaft position sensor (I used Hitachi CPS0008) is reached from the right (US passenger) side. I used a 1/4" ratchet with a standard (short) 10mm socket to remove the retaining bolt. Nothing else had to be removed to get access to it. Disconnecting the connector from the sensor took a little bit of figuring, though. In the end, the "tab" (that you would normally think to press and then pull the connector and sensor apart) is not pressed down, but instead pushed in, in the direction of the sensor. This also releases the sensor and pushes the two apart. Then you just push the new sensor onto the connector.
• I also found it best to access the left bank camshaft position sensor (I used Hitachi CPS0005) from the right (US passenger) side of the engine bay. It's a little tight to get to the retaining bolt, but it's manageable. I had pulled the intake tract to try and see if access from there was better, but it was not.
• I found it easiest to remove the sensor with the connector still attached, and then separate them.

The engine fired right up and ran good on a quick 10 mile test drive with varying speeds. And, the tachometer was smooth again, with no jumping/bounce/variation at steady speeds.