Contour Enthusiasts Group Archives Forums General Troubleshooting P0340 code and valve chatter at 2K RPM

Hello Forum,

I have a 1999 Mystique with 60K miles. Its an automatic with the Zetec 2.0L engine.
I bought it used and it had been started in a couple of years. Over a period of the last few weeks I ran the tank dry starting the car daily, etc. and replaced the two year old gas and dropped in Techron. Its starts and runs fine, but after its warmed up I get a P0340 when the car is restarted after dring for 10-12 minutes. The timing belt and tensioner seem ok, but probably should be replaced long term I suspect. I replaced the cam shaft position sensor as a shot. I also see 14 volts on one of the two pins when disconnected and the car is running. The other observation, and may be inherent in the Zetec with VCT, is I hear some valve train noise in the 1900-2100 RPM range. I ohmed out the VCT solenoid and its at about 4 ohms. I also see 14 volts on one of the two connector pins. When I unplug the VCT solenoid the valve train sounds great driving. As expected however I get P1380 along with the P0340 code however. Could the VCT solenoid assembly be causing the P0340 as the only code?. I guessing yes and bummed at the replacement costs to find out. I also had the oil changed after I was getting the P0340. I have drine thae car about 100 miles at this point with new gas and oil.

Thanks much!!!

BobM.

I would check all the wires coming from the camshaft position sensor. Make sure there are no naked places and everything is plugged in good.

As far as the VCT solenoid if the car sat for 2 years you should get some engine cleaner and run in it to clean the varnish etc out. It maybe stuck. Make sure you use the right weight oil.
Here's another test you can do to make sure it is mechanically working: With engine running, using a jumper wire, backprobe the ground side of the VCT solenoid. Then rev the engine up to 2,500 to 3,000 rpm and momentarily ground the VCT solenoid; again, only for one to two seconds. You should hear a noticeable difference in the way the engine runs. Make sure you only leave it on 1-2 seconds or you will mess the VCT solenoid up

Welcome .

DEC1000,

Thanks for taking the time for the write up. I have checked the postion sensor wires a few times. I may and try and get an ohm meter reading from the PCM pins to the sensor connector. If I connect an OBD reader when the car is warmed up I can see a pending P0340 and then when I start the car a 2nd time after driving for 10 minutes I get the MIL light P0340. I'm starting to think it may be the PCM as I can start the car 5 to 6 times when its cold and I get no codes. I'll give the VCT a cleaning and a test as well.

Thanks for the tips,
BobM.

Steve,

Thanks for the pointers and procedures to get closer to my problem. I have tried to locate docs on the 340,1380,138X codes that are referenced in a TSB for the Zetec, but I have had no luck. On the PCED procedure, do you have a link and such that I have missed to guide me?

Thanks much!
BobM.

Ps; I see your login is "project89SHO". I had a Green 93 SHO I bought used in 94 and then traded it for a new 95 Red SHO. I sold it 2 years ago :^(

See your PM.

Yeah, that's my 2nd SHO. $200 and saved it from the junkyard. $3,000 in parts, tires, accessories and 45k miles later it still is on the road at 242K and runs great. It still looks like crap.

3rd SHO is a very nice looking white 94 ATX with 190K and a bum tranny and worn out front suspension. The tranny is currently in pieces in my basement waiting for a couple of parts and some specialty tools. Hope to hav it back together in about two weeks with a rebuild tranny, rebuild suspension and steering, and new rod bearings. Except for the color of the interior, this one is a twin of my 1st SHO.

I always wanted the pretty red SHO, my 89 is that ugly-assed Current Red, though.

Steve

Steve,

Thanks again for all your help. I check the info you pointeed me too and update on what I isolate for the P0340 code further.

Bob,
Ps; Yep the Red SHO says fast.... Have similar taste in workhorses as well. I have a 2000 F150 5.4. Put on a dual flowmaster a few weeks agao... Sounds great...

My P0340 saga continues....!!!

Cleared OBD codes with reader and/or battery ground to positive after every step.
New CPS Sensor
Ohmed out PCM connector to CPS
Measured .1 to .5 volts AC scale on active CPS when changing engine revs.
OIl/filter change.
Replaced PCM (yes I know!!!)
Slight rough idle after 5-10 minute warm up thinking P0340 is just a symptom of slight misfire.
Replaced PCV, wires, plugs, Coil pack, air filter, fuel filter.
Car has been driven 3000 miles since my original post in February and a couple of tanks with Techron. Runs fine and goes to redline with no hesitation, etc,
Only after warm up P0340 and emissions inspection failing :^(

Belt, tensioner, look good. Could it be the timing belt?
How do I tell if its the flex plate?
Vacuum leak?

Help..!!!
BobM.

Bob,
I'm going to jump in here on the valve clatter. Random thoughts:

Have you tried to change to a lighter or heavier oil? If it is clatter that is cam or lifter pump-down related the oil change may change the noise and it would isolate the problem to that area specifically. They are hydralic bucket tappets so the oil change would effect them too of they are tuckered out (hard to believe at 60K though). Have you pulled a cam cover to see if the cam is OK (not scored or otherwise beat-up). As long as you have the cam cover off, measure the valve to tapped gap (heel of the lobe to tappet).

Getting away from the valves, I remember the first time I heard the saturated circuit style fuel injectors I thought the valves were bad. They click like crazy and you might be hearing that.

Have you tried the old "yard stick to the ear" trick to isolate the where the clatter is really coming from? Get a yard stick and put place it on different areas of the engine and then to your ear. You'll hear many things this way and maybe you can find out if the clatter is coming from the cams or from another area nearby.

An accessory belt will click when it gets old but it is a different type of click of "clatter". Different in that the timing of it is different than the valve train. Less rapid. Timing belts: not that I have ever heard.

As for the codes, if this car was sitting with bad gas in it. You probably need a fuel injector service. The car is going to need the injectors serviced at 80K anyway so why not now? Adding stuff (Techron or whatever) to your tank will not clean a fuel injector that is dirty they must be removed. If you have lean injectors the CPU will try and compensate and you could be getting into a "lean-rich" loop. Here in the Seattle area we have a place called "Dr. Injector". They clean them for about $35.00 a pop and they also flow check them before and after. They also do it by mail if need be. Look for something similar in your area. They come out real easy, take less than a day to get cleaned and are a good D.I.Y. project.

That's about all I can think of of right now. Hope this helps. Good luck.