If my car sits for over a week without being started, it cranks for a long period of time when i try to start it. If i start it every other day, it fires right up, regardless of how cold it is outside. I plug it into a battery maintainer and have installed a new battery recently. Any ideas?

 

Attach a fuel pressure gauge to the fuel rail and do a leak down test.

 

I would look into performing a very comprehensive fuel pressure test. Record what the pressures are (Key on, not running; also do a leakdown test on fuel pressure) especially after it sits for awhile since that is when the problem is most evident.

Edit: crap, can't type fast enough lefoy84 beat me to it.

 

http://members.shaw.ca/corvette86/6E3-B%20Symptoms.pdf
http://members.shaw.ca/corvette86/Co...0View%2086.pdf
http://members.shaw.ca/corvette86/Fu...mDiagnosis.pdf

 

I believe the general consensus here is a bad injector
Very common problem
Do a search on here and enter injector
Youll see

 

Make sure your CSV is working properly. A fuel pressure test is a good idea also.

 

I would make sure the battery is fully charged. What is the voltage reading on the dash after it sits a week? For the CSV...when it is not working, the cold cranking time will be exteded. Say you might have to crank the engine 3 or 4 key turns before it starts. The 85-88 ECM's are slower and don't allow enough fuel for cold starts. Even though the 89 ECM is a 165 like the 86-88, they are more advanced and do add enough cold starting fuel. 88 was the last year of the CSV. This is probably not your problem.

I really don't think it is a leaky injector problem either. If the battery is fully charged and it take longer to crank then it's time to find out what the engine is lacking. I would start with the fuel supply.

When the key is turned "on" , the ECM sends signal to the fuel pump relay. From there the fuel pump is energized for 2 seconds before the signal is lost. This builds fuel pressure. After you start cranking and once the oil pressure reaches 4 psi, the oil pressure switch closes the fuel pump circuit and sends 12v to the fuel pump. Now, the oil pressure switch is a back up for the fuel pump relay incase of it's failure, so your not stranded.

You need to use a fuel pressure guage attached to the schrader valve on the fuel rail to see if you are getting fuel pressure and how much. If there is adaquate pressure there (40 psi) before cranking, then check for spark by using a spare spark plug attached to each spark plug wire. Get about 1/2" away from the exhaust while the engine is running (be advised not to touch the lead or plug with the engine running or the experience will be shocking) or with someone cranking the engine after the injector fuse are removed. There should be a bluish/orange spark. Everyone has a different way and this is what works for me.

In the end I think you will find the battery is not fully charged or there is a problem with the connections at the power terminal behind the battery. Perhaps even a bad ground.

More info is needed.

 

thanks. This weekend i will borrow a fuel pressure gauge and see what happens