extended crank time problems
Thread Starter
Heel & Toe
Joined: Aug 2004
Posts: 15
Likes: 0
extended crank time problems
My 1989 Vette is hard to start about 90% of the time. It always starts, but it has to crank way longer than normal. I smell gas when this happens most of the time. I checked all the ignition components, and evidently the previous owner has been all over it replacing plugs, wires cap and rotor. Everything looks new. I did notice the car has an aftermarket hypertech chip in the ECM. I was told that was the source of the problem.
Team Owner
Joined: Mar 2001
Posts: 54,124
Likes: 30
From: Cincinnati, Oh USA
You have the symptoms of leaky injectors. Measure the fuel pressure at the shrader valve on the end of the fuel rail after you turn the ignition on and then off. The fuel pump comes on for 2 seconds and goes off when you turn the ignition on and the fuel pressure should go to approximately 40 psi and it should not fall. If it falls rapidly, you have leaky injector/s which cause a too rich mixture during start. The solution is to replace your injectors.
Melting Slicks
Joined: Nov 2000
Posts: 2,469
Likes: 6
From: Winchester Ontario
Dropping only 5 psi in 30 minutes is definitely acceptable.
I read one thing on here as a test for leaking injectors.
Key on, engine off. Depress gas pedal to the floor and hold it for 10 seconds. Release gas pedal and try to start car. If it starts right up, it's an injector issue.
I guess this procedure rids the engine of gas fumes. I'm pretty sure it was 65ZO1's procedure that I got there.
****EDIT****
I just copied and pasted this off 65Z01's site.
How to Detect Leaking Fuel Injectors
Symptom
Upon restarting an L98 after it has been standing for a while it cranks for a longer time than if started when totally cold or very soon after shutting it off.
Test
Before starting the warm engine, with the ignition key off, hold the accelerator full open for say 30-60 seconds.
Release the accelerator, and start the engine.
If it now starts quickly, the problem is a leaking fuel injector.
Acknowledgement
This diagostic tip came from Gordon Killebrew during an instruction session at Corvettes at Carlisle 2001.
I read one thing on here as a test for leaking injectors.
Key on, engine off. Depress gas pedal to the floor and hold it for 10 seconds. Release gas pedal and try to start car. If it starts right up, it's an injector issue.
I guess this procedure rids the engine of gas fumes. I'm pretty sure it was 65ZO1's procedure that I got there.
****EDIT****
I just copied and pasted this off 65Z01's site.
How to Detect Leaking Fuel Injectors
Symptom
Upon restarting an L98 after it has been standing for a while it cranks for a longer time than if started when totally cold or very soon after shutting it off.
Test
Before starting the warm engine, with the ignition key off, hold the accelerator full open for say 30-60 seconds.
Release the accelerator, and start the engine.
If it now starts quickly, the problem is a leaking fuel injector.
Acknowledgement
This diagostic tip came from Gordon Killebrew during an instruction session at Corvettes at Carlisle 2001.
Last edited by black_89_vette; Sep 3, 2004 at 08:33 AM.
Thread Starter
Heel & Toe
Joined: Aug 2004
Posts: 15
Likes: 0
I repalced the ECM with a stock part from a 1987 IROC that a friend had laying around. It seemed ok at first, but as I drove the car last night the hard start came back. I guess fuel injectors, right? 
