2007 CX7 Starting/Not Starting

Hello, I have a 2007 CX7. I can start it. It will run for a little while but when I put it in gear it will die but after I do that, it will not start back up. It tries but doesn't start. I replaced the fuse for the injectors. I'm not getting any codes either but the TSC light is on. The car has around 107,000 miles. I did replace the bypass valve L3K9-20-2 50A as the vacuum nipple was broke. I haven't had the car very long and bought it at auction.

Any advice would be greatly appreciated.

Thanks

Jeff
 
Ok, those latest developments certainly appears to take the transmission off the hook, and it would seem to be something going on with the engine.

It's not clear from your prior posts if you ever tried starter fluid when it stalled and wouldn't restart. If not, you need to do that in order to be able to determine if the problem is fuel or spark.
 
Upvote 0
It would not restart with starter fluid. I tried a couple different times.
It’s almost like a safety switch. I’ve checked all the fluids and they are good.
 
Upvote 0
Although it would seem that the failure to start is a no spark issue, I suggest confirming that by removing the plugs, ground them on the block, and watching for spark while a helper cranks.
 
Upvote 0
I just went out and tried to start it. Wouldn't start. I put my scanner on my phone (cheap one goes to my phone) It gave me a P0335 camshaft Position Sensor. Could that be the whole issue? Maybe it was hitting intermittently?
 
Upvote 0
Any issue with the crank sensor signal could certainly produce the symptoms you've been seeing. However, a bad crank sensor signal does not automatically mean the crank sensor is bad and is the problem.

You should definitely examine the crank sensor connector and the near wiring for damage, and also test the wires with a multimeter. Also in play is the reluctor wheel, and perhaps even the flexplate, however it's difficult for a DIYer to test for problems with those parts.


Of course many people just hang on a new sensor. Personally I'd always want to test first instead of just throwing parts, but your vehicle, your choice.
 
Upvote 0
Hello, So I went ahead and replaced the sensor. I didn't have a tester. Put it on. It cranked right up. Ran for about 10 minutes and died but I was able to start it back up (which in the past I couldn't). I then put it in gear and it would die immediately in drive but in reverse it would chug then die. I was able to restart it about 5 times then it wouldn't. I waited about an hour. Went out there and it started right back up. What i did this time is turn the steering wheel, it died. I cranked it back up without any issue, tried turning the steering wheel again and it died immediately. It appears its not putting the transmission in gear, it's putting the engine under a load. Any thoughts on that? THANKS!
 
Upvote 0
and on my scan tool my o2 sensor 1 doesn't register. The 02 sensor 2 does but not sensor 1. When I say it doesn't register... On my phone app that connects to the car. No matter how many RPM's at idle the O2 Sensor 1 says O.OO
 
Last edited:
Upvote 0
Heated O2 sensors don't start sending output immediately, and the ECM doesn't even use O2 sensor until closed loop occurs. How about that P0335 code? As I mentioned previously, an issue with the crank sensor signal would fit in with all of the problems you have been reporting.
 
Upvote 0
Heated O2 sensors don't start sending output immediately, and the ECM doesn't even use O2 sensor until closed loop occurs. How about that P0335 code? As I mentioned previously, an issue with the crank sensor signal would fit in with all of the problems you have been reporting.
I replaced the crank shaft sensor. The code is gone but it still does the same thing. But It does restart. But that is what got me to the point where it appears that the engine dies under load.
 
Upvote 0
I keep coming back to that P0335 code as being the only significant, tangible piece of information as to what might be going on with your vehicle. You wrote that you don't have a multimeter, and without one there isn't any testing that you can do on your own. And, even if you did have a meter, a crank signal can only be fully evaluated with an oscilloscope or the proprietary dealer tool.

So my suggestion, if you can swing it financially, would be to pay to have a traveling mechanic who owns a scope, take a look at the crank signal. However, if they want to charge an outrageous amount to test the signal, a better alternative might be to just spend less $$ and buy the lower priced scope, which would let you continue to work on this problem on your own.
 
Upvote 0
Back