Hard to start

[Guest]

I started to have a hard time to start the engine in the morning. Its very cold yet( 45 degrees). I replaced the ECM last winter for the same problem. I sprayed water on the plug leads and they seem to be okay. I have listened to the fuel pump when ignition is turned to the on position and it seems okay. I dont get any error codes on the CRT.<P>PS. When I go into the diagignostic mode and read the value of the various functions how do I know what the correct values should be?<P>Any help would be welcomed. <P>------------------<BR>

[Depley]

Might think about having the fuel pressure checked, I did that and was told my fuel pump is leaking slowly back into tank causing the entire system to have to be replentished at each cold start. When he said replacing the fuel pump would cost me $400 I said I will live with the hard start<p>[This message has been edited by Depley (edited 09-20-2000).]

[Guest wally888]

I am still searching for causes of hard start on 2 89's.Both have good wires, plugs and clean filters.<BR> I cleaned the IAF's (inlet air flow) on both, no change.<BR> I have used Techron in one of them, no change, but the other one got better!<BR> Guess fuel pressure is next and then oxy sensor?

[Guest]

I have seen this a few times and it sounds<BR>like either the fuel pump is losing its prime and bleeding back, or injectors<BR>are bleeding down. The other thing which<BR>does happen quite frquently is the fuel<BR>pump relay. Hope this helps.<P>First thing to do is a fuel pressure test to see if the pressure bleeds off quickly after<BR>the key is shut off. If it does the injectors are leaking. Check to see how long<BR>it takes the fuel pressure to come up when you start the car, or if the pressure drops<BR>when you crank the motor.<P>Brad Pennington<P>------------------<BR>

[Guest Hitzzz]

I have the same problem with my 1990 that I have been working for the past several weeks. Have replaced the coil pack, fuel regulator and have the pump relay yet to do. QUESTION .... how long should pressure stay in the fuel system ...???? When I replaced my fuel regulator there was no pressure when I loosened the fuel line from the regulator .... the car had been sitting for 3-4 days ... If the injectors leaking shouldn't they be wet with gas..??? I used a bottle of Techron(sp)and the wife thought it started a little bet better .... but still not the way it used to ...

[Guest]

I had the problem in my 89, was the fuel pump relay. Without the relay, fuel pump works off oil pressure, this took a couple seconds of cranking time to get proper pressure. There's a test connector on the relay side of engine compartment, you can put meter or test light on this. Turn on the ignition and you should see voltage, this will tell if you are getting input to the relay.

[Guest]

The length of time they will hold seems to vary from car to car. Mine bleeds down to about 20 psi or so in about an hour. My injectors were just cleaned with ultrasound and backflushed. I believe they are acting normally but the rest of the system has 92k on it, so it probably isn't perfect. I don't believe any of the modern systems will hold much pressure overnight but it shouldn't really drain back to the tank. If it does, the couple of seconds the fuel pump runs from the key on may not be enough to bring the pressure up sufficiently to start the car. By way of information, when I attach my gauge, which kills any residual pressure, the pressure jumps right to 44 psi as soon as the key is turned on.<P>------------------<BR>Hal, btk@vbe.com

[Guest wally888]

My big can of Techtron is gone. Will replacing oxygen sensor possibly cure hard start. Is the sensor cleanable?

[Guest]

O2 sensor has no effect on starting. Once the engine starts and goes into closed loop operation, the O2 sensor is important.<P>------------------<BR>Hal, btk@vbe.com