Problem with Starting with an odd twist

[BlizzySHO]

Hi guys,
I'm having a problem with my 1995 ATX SHO. The car will not start always, but I have found an odd pattern to the starts. The car can sit all night out in the freezing cold and start up fine first try in the morning. Now, if I were to drive the car a bit, shut it off and try to turn it back on, the car has problems. It will crank but no start. After some time and tries, if I apply the gas pedal, the car will start. If the car starts this way, however, the tachometer will not work for a good 10 minutes. Eventually it kicks on while driving. If the car were to then sit for hours, it will start up fine. This problem started in the winter (I'm in CT.)
Anyways, this is very annoying (gas stations are especially bad) so I brought it to a local garage to check it out. The guys here know SHO's (most of them own or have owned one) and they cannot find the problem. They replicated it, but spent spent hours trying to diagnose it and are coming up with nothing. They said at one point the codes returned a bad EGR valve but they know that's not the problem. They also ruled out the starter. So the car is coming back to me, problem still occuring but not fixed. Any ideas?

 

[Ishodu]

If your not getting any codes. You can check the link in my sig to find out how to do it yourself. My bet would be on a Cam position sensor, this is if the car is only hard to start. Did it ever just dye like that when running with no tach?

 

[BlizzySHO]

Did it ever just dye like that when running with no tach?

So far the car has never just died without the tach.

 

[F-22 Raptor SHO]

Since the car has not just plain cut out while driving and is only acting up after you drive it around a bit then shut it off, my money is on the IAC being dirty. The Idle air Control Valve (IAC) which is the cylindrical shaped device on top of the motor has the wire plug attached to it. Mine is black in the picture below on the right side:

You need to remove that and clean it out with carb cleaner. Its function is to allow some air into the motor during startup. When you apply the gas, you are opening the throttle plate a bit to allow air in manually. go to shotimes.com to see how to get that off without taking the intake off.

 

[jaded93atx]

That is textbook camshaft position sensor (CID)failure. Its a round black sensor with a couple of wires going to it on the upper rear bank of the engine across from the power steering resevoir. It is around 29.00 at AutoZone for the wells brand. Run a search here on CID and you'll find plenty of info (and pics)about it. That garage you are getting work done by is not doing you any favors...they should have recognized it as the problem right away, especially if "they know shos", it is a common failure and displays a code 214. Learn to pull and read your own codes, it will save you a lot of time, money, and unnecessary speculation.

 

[greenbeanmtx]

These same symptoms were happening to mine a while back and it turned out to be my cam position sensor..... Mine didnt trigger any codes either..... my tach would not work for about 20 to 45 seconds and then it would come to life. Id clean the valve like they mentioned and if that doesnt fix it then consider the cam position sensor.... Its pretty easy to get to and the part is about 35 bucks from autozone. But try the free stuff first. Good luck, i know its very frustrating and embarassing as mine was too!

 

[jaded93atx]

heres a pic of the cid

 

[Ishodu]

So far the car has never just died without the tach.

My money is on the Cam Sensor then.

 

[BlizzySHO]

Just providing an update, replaced the camshaft position sensor and so far so good! The car is starting up good again! Thanks for everyone's help and hopefully this helps others as well

 

[SHO Revisited]

I read this post and was having a similar intermitent problem on a 94 ATX and decided to change the CID. Went to AutoZone with Wells part # and was told it wasn't a required part for my car. I told them I would take it anyway. Was quite easy to install moving the PS reservoir. Hope this works, so far so good.
Thanks for the everyone's help.