No Start problem

OK all, here is my situation. 91 SC w/ a reman motor. I just recently had a no start condition. Car will crank, but not start. Its getting fuel cause you can smell it, and when it finally fires, it will blow off some black smoke. I did not see the upshift light come on when it wouldnt start. This happened once when the car was cold, and once when the car was hot. I was thinking it might be the DIS? Anyone have any opinions????

Hey greg D

In my case it was the fuel pump it was working but not supplying enough pressure. I know it sounds crazy. but others have also had this problem. I had no pressure at the rail but if I started the car it would run real rich I guess it was the eec trying to keep the car running . black smoke is caused by a rich condition. When the car would start my pump would only flow at 20psi and that is not enough. star up pressure at the rail should be between 35 and 40 psi. when the car is running the fuel pump should flow at 40 psi then when you step on the gas pressure should go up. Another possibility is the Fuel pressure regulator on the rail. There is a schrader valve on your fuel rail where you can hook up a fuel injection pressure tester . That is a good pplace to start.

Anyone else have any thoughts? Do you really think it can be fuel related? My expierence has been if it is a fuel pump, it will usually happen when its hot. This happens usually when it's a cold start.

TTT

Well Greg D

Perhaps Cam sensor. Reads like your crank sensor is sending the pip signal this would cause the car to load up black smoke during start up. Do you have to turn the key off and then on 5 or 6 times before it starts . If so this might mean you have a bad cam sensor. So your EEC is going into FMEM and trying to keep the car drivable by guessing when and which cylinder to spark to get the car started. Normally the cam sensor sends a CID signal to the eec to let it know which cylinder to fire to start car. Your car should start on the first attempt and should start before 5 seconds. If you have a bigger battery meaning 1000 cranking amps rather than 650 it should start even quicker. Also you should not keep the starter turning over more than 6 SECONDS if it has not started before 6 seconds is up then it is not going to start . So after 6 sec turn key off and try again.

You are right. It will take about 5-6 times, then it will start.

Cam Sensor

My guess too. They are pretty inexpensive.

When installing a new one, don't they have to be set a certain way? Or is it simply a remove and replace type deal?

I just put a new one on my 95. You only need to use the special adjustment tool if you remove the cam sensor housing (I think that's what it says in my helms manual, but I think it's really if you remove the rotor), not the stator. You just take the two screws out and install the new one. But, do make sure that the red rubber seal doesn't stay on the plug (from the old sensor). When you go to install the plug into the new sensor, it makes it kinda IMPOSSIBLE to install into the new sensor (which comes with a red rubber seal inside the connection point). I think I learned some new cuss words that day.

Haahaaaha!!

Michael,
I learn new cus words every time I work on my SC.!>!>!

OK all, here is my situation. 91 SC w/ a reman motor. I just recently had a no start condition. Car will crank, but not start. Its getting fuel cause you can smell it, and when it finally fires, it will blow off some black smoke.Sounds like the engine is flooded, try this next time it does'nt start on the 1st crank. Hold gas pedal to the floor and crank engine with pedal down until it starts. When engine starts let off the gas pedal and check for black smoke coming out the tailpipes. If you get black smoke your engine was flooded. A dirty partually stuck open injector will leak gas into a cylinder when you shut the engine off and flood it. A stuck injector will spray fuel into that cylinder until it bleeds off the 40 psi that the fuel lines are running at when you shut off the engine.

I did not see the upshift light come on when it wouldnt start.Thats good. The crank sensor is fine then.

This happened once when the car was cold, and once when the car was hot.Sounds like a clasic stuck open injector. Try a good fuel injector cleaner for a tankfull of gas and see if it helps, if not you will have to try something else.

I was thinking it might be the DIS? I dont really think so. Have you pulled the codes? If so what were they? I'd almost bet you will have a HEGO code in there.