Month and year is on the sticker on the driver door, near the latch. There are vin decoders online that will give the exact build date. www.compnine.com is one of the better ones. The vin decoder will not work for the Camaro, 17 character vins started in 1981. The Camaro would fetch a healthy price here in the States

 

The Camaro has a healthy price over here too :-)
You can see more of it here: Hem - Protouring.se

I have finally tested the pressure, at the fuelrail I get 60 psi and it goes down to 55-54 when the pump stops. The the pressure is slowly decreasing.

I guess it's time for a new pump assembly.


Jan

 

Not necessarily. Both of your readings are borderline. The problem could be in the plenum, or in the fuel tank. You need to check the maximum output pressure and leakdown of the pump. Post #6 explains. Here is a list of parts that you will need to make the adapter: http://i561.photobucket.com/albums/s...ps5c876ad4.jpg

 

I've noticed over 50psi and you may be able to get it started and run OK. If pressure drops a little more it may run but run poor. If it drop just a little more its like shutting the key off. If you can't get the pressure to build back up to at least 50 again it won't restart. Cycling the key on and off again many times after it dies without trying to start it, then after many cycles try starting. It may run again until pressure drops a little. My problem in this post may solve yours. https://blazerforum.com/forum/showthread.php?t=85337 while temperature effects crank sensors, your original suspect, it also apparently effects fuel pump performance. When the pump is functioning in its acceptable window of pressures everything is great but the moment it dips below that it can be just like turning the key off even though the pump is still running.

 

Lancelot, it is like you describe. I t will occasionally start and run for a short while and then i dies. I can hear and feel that it starts to bludder and backfire like it is running out of fuel.

I have measured the fuel pressure after the filter and it is 85-90 psi. I couldn't get the hose to stay on for any longer time to see if the pressure dropped. But at least there is good pressure at the filter.

Pressure at the manifold is 60 and drops to 50-55 when the pump shuts off. I haven't been able to check the pressure when it is running.

Could it be the pressure regulator in the injection manifold?


Thanks

Jan

 

One more thing.

If I run the fuel pump from the red wire connector in the engine bay I can hear a rattling noise from the manifold. I guess it is the regulator that makes the noise.


Jan

 

Jan, The noise you're hearing is fuel passing through the regulator, being sent back to the tank, (normal).

There are no fuel pressure specs for "engine running", all tests are done with the engine off. 85psi to 90psi is within specs, but it's a bit low. We really need to know what leakdown pressure is after 10 minutes. Here is a list of what you'll need to make the adapter for checking pressure and leakdown at the filter:

 

Ok now I have measured the pressure after the filter.

I found this connector, Dorman 800-082, that is the same connector as on the fuel line from the filter.
Dorman Products - 800-082


The readings I get is as follow, I did three test with the same result.
When pump is running I get 97 PSI.
When I shut it off it goes down to about 85 PSI and after ten minutes is slightly under 80 PSI.

I hope that can help.


Thanks

Jan

 

The pump is fine, max pressure and leakdown are both WELL within spec.

From post #35:
Your regulated pressure, (at the service port) at 60psi is the lowest allowable, but technically within spec. It will cause a slightly leaner fuel mixture, and possibly cause a hesitation on acelleration, and possibly longer crank times with colder ambient temps, (below ~20F). Some regulators are adjustable, some are not. If it is adjustable, there is a very small, (15??) torx head screw on the rear of the regulator. If it's not adjustable, a new regulator should regulate the pressure a little higher. I like to see pressure at 63psi for best performance.

Your leakdown to 50psi-55psi is also borderline, but within spec, and it might come up with a higher regulated fuel pressure.

Bottom line: Fuel delivery is not causing the problem, unless the pump motor is intermittently losing power or ground.

Have you checked the ignition switch? 1997 ignition switch is unique to that year and is known to cause some weird stuff to happen, ignition and fuel pump circuits included. Contacts in the switch get burned and can't make a good connection. Check this out: https://blazerforum.com/forum/articl...-switch-33465/ These diagrams are for 2000, 1997 is not exactly the same, but similar.

 

Thanks.

I'm inclined to believe that the regulator can be the problem. Since it will run for a short while I can connect the pressure instrument and see what happens when it is running.

When it is running it's not doing it OK, it hesitates when you press the pedal and shuts down in a way that indicates fuel feed problems, even can backfire.

I'll check this and come back.

If it was the ignition key wouldn't that cause problem in other electrical circuits, i.e. other things should shut down as well? Or are you saying that the fuel circuit through the ignition key is separate?


Thanks


Jan