2000 Grand Am Engine Replacement

[jeff2465]

I have a 2000 Grand Am with the 3.4 engine. Old engine was bad - still started, but operated on less than 6 cyls. It has the Calif emissions version, so got a used engine with the Calif setup (as I understand, this involves the additional air tubes going into the heads). Have the new engine installed, but it will not start. Cranks fine, has good spark, crankshaft sensors are both opeating as is the camshaft sensor. The fuel pressure on the rail is 52 psi, and repeatable. Seems like it is not getting fuel as the plugs are dry. We did shoot in a small amout of starting fluid and she took that, so I am guessing that the ignition is ok. Checked resistance on the injectors, and they all read about 12 ohms at room temp. The injectors are not readily accessible, so we did not put a noid light on the connectors, but did look at the voltage going to one of the injectors using an analolg meter. I expected to see a spike to 12 volts, but did not see anything. The system is acting like the injectors are disabled. I would be grateful for any additional ideas to try. Thank you. Jeff

[xeroinfinity]

Sounds like the pass lock was triped.
Try the passlock relearn and see if the injectors work after that.

Security relearn procedure:

1) Attempt to start the car by turning the key to the Start/Run Position.
2) Observe that the vehicle fails to start and that the security light is illuminated.
3) Release key to the 'ON/Accessory' Position. (DO NOT turn key to the 'off' position.)
4) Allow the vehicle to sit with the key in the 'ON/Accessory' Position for no less than 11 minutes.
5) Turn key to off position and allow the vehicle to remain in the 'OFF' position for no less than 30 seconds.
6) Repeat #1 - #5 for 3 cycles.
7) On 4th attempt, car should start.

NOTE : Since this is a fairly long procedure, I would limit all electrical sources, such as disconnecting headlights, to prevent discharge of battery.

NOTE 2 : It is SAFE to wait LONGER than the allotted time, but it is not safe to wait less time. I.e. 12 minutes instead of 11 minutes should be safe; however, waiting 10 minutes instead of 11 minutes is not safe.

Properly executed, this procedure should take approximately 35 minutes to complete

[jeff2465]

Thank you for the response. I will try the procedure and see what happens and will post what happened.

[xeroinfinity]

something else I forgot, check the injectors fuse.

[jeff2465]

Have tried the passlock procedure with no luck. Have checked fuses we could find, but did not see one marked for injectors. Do you know if it is an inline fuse? We have looked at the fuse center under the hood, and the 2 on the sides of the instrument panel. Do you know if there are any others? Will keep checking for the fuse. We are also looking at missing grounds for the PCM, but that also tests ok. If the injector is pulsing, we should be able to hear it with a stethascope I believe. We verified fuel pressure at the rail when it cranked, and it stayed at 54 psi, which from the data I have, that looked to be acceptable. I was also going to check the wires going to the injectors and look at the voltage. I am guessing I should see some sort of dc pulse. I will keep you posted. Thank you again for the help.

[xeroinfinity]

I guess thiers only one fuse for hte injectors in the underhood FB, #48, I would also check #5.

Make sure your crank and cam sensors are pluged in to the ICM and working 100%.

You can test the injectors from the large plug on the pass side/rear of engine, its a very large plug.
And make sure the engine grounds are clean and tight.

You could have a large amount of air in the fuel rails, does gas spray out of the shradder valve when you push it in ??

[jeff2465]

Both fuses check out ok.

Cam and both crank sensors seem to be working ok. I tested them using a procedure you listed in another post and the voltage levels were ok. We did swap the cam sensor with a known good one, but no change.Also check spark at one of the plugs, and it seemed strong. Also pulled a plug and it was dry - I expected to see a wet plug.

We bled the fuel rail until we had a steady stream, and there was a bit of air, but still no success.

We also checked the fuel injector signals, and we did get a pulse using a test light. My voltmeter did not accurately catch the signal, and I do not have access to an oscilloscope. I can get one next week and look at the signal in more detail.

We checked the grounds before, but it is worth the time to make a double check.

I am going back to the book again. This is one of those things I think, that when i find it, it will be something simple. But until then, I will be scratching my head. Thanks for the support.

Jeff

[jeff2465]

Got it running. It ended up that the injectors were all stuck - hard to believe all 6 would stick. I saw a site that talked about fuel quality, and I suspect it had been some time since the "new" engine saw fuel, and maybe not the name brand fuels. The site said to lightly tap the injectors. We did that. Then we removed the 3/8 inch vacuum hose just before the throttle body, and we slowly injected gas in the inlet air stream. She took the fuel, and the heat and vibration must have loosened them up. We let it run for a while and now seems to be ok. Thanks for your help. Jeff

[xeroinfinity]

Glad to hear !

I figured something like that was keeping them from firing up.

If you would have had a high quality scan tool it would have shown they werent firing fuel, and you could manualy pulse them, which usualy gets them going.

Fuel does gum up whether its good or bad fuel.

I'd run some injector cleaner through it a few times to clean them up thuroughly, sea foam works great.

[jeff2465]

Thanks again. Will get the Sea Foam.