Fired up the engine today!

MalibuRacing

Top Fueler
May 5, 2003
3,465
0
36
www.maliburacing.com
It took forever, but we finally had the time to get out and fire up the engine today. The computer is sending the signal for the fuel pump, but it does not seem to have enough power to even activate a relay. So, I need to talk to Jesse at Wait4Me Performance and see if he has any ideas. We "hot-wired" the fuel pump to get it running. It fired right up and idled great from the start! It sounds great, can't wait to drive this thing!
Right click and save as: Engine cranking/running (41 MB)


Exhaust is 2 1/4" duals with 3 chamber Flowmaster "knock-off" mufflers. It is pretty quiet at idle, but has a nice sound when you get on it (if you like the Flowmaster sound).
Right click and save as: Exhaust sound (5.7MB)

Next up is tidy up the under hood wiring and complete the interior.
 

350ss

New Member
Nov 13, 2008
4
0
0
Congrats on the running engine. I've been following along with your builld since the beginning, nice to hear things are coming together.

Regarding the fuel pump relay, the pcm activates the relay by providing a ground rather than +12v which it sounds like you have it hooked up right now.
 

StreetBu

MalibuRacing Junkie
Mar 21, 2004
4,158
3
38
Upstate NY
=D> =D> =D>

Glad to see its up and running. Believe it or not the easy part is over.....Always seems to take forever to tie up all the loose ends and reinstall everything. CONGRATS!!!
 

MalibuRacing

Top Fueler
Thread starter
May 5, 2003
3,465
0
36
www.maliburacing.com
388bu said:
Congrats Phil!

Thing sounds like a baby at idle just like mine. :lol:

Im curious what you find out about your fuel pump issue.

I tried a few different things, but it just will not drive a relay. It has 12v when not connected to the relay. But, when I connect the relay, it doesn't seem to push enough current to activate the relay? I will give Jesse a call and see what he says. :-k

Worst case, I guess I could "hot-wire" the fuel pump to come on when the ignition switch is in the on position....
 

MalibuRacing

Top Fueler
Thread starter
May 5, 2003
3,465
0
36
www.maliburacing.com
350ss said:
Did you read my post above?

Yes, but are you sure that is correct for the LSx series? The guy that did my wiring harness said that the PCM provides 12 volts out to connect to the realy coil. Then, connect the other side of the relay coil to ground. See below for how I (tried) wiring it. It is definitely putting out 12 volts until I connect the relay. I tested the relay and it works fine.

fuelpump_wiring.JPG
 

350ss

New Member
Nov 13, 2008
4
0
0
Sorry, I blew that one. lame_sign.gif
You are correct...I got my wires crossed when looking at the schematic. So basically this wire should activate for a few seconds when you turn the key to "on" to prime the fuel pump and then will turn off. Then when you start the engine it will turn on again and stay on when the engine's running.

Does it cycle +12v on/off when you turn the key on?

The only other thing I can think of to check is that the wire is pinned correctly. The wire should go to pin 9 on the red pcm connector.
 

MalibuRacing

Top Fueler
Thread starter
May 5, 2003
3,465
0
36
www.maliburacing.com
350ss said:
Sorry, I blew that one. lame_sign.gif
You are correct...I got my wires crossed when looking at the schematic. So basically this wire should activate for a few seconds when you turn the key to "on" to prime the fuel pump and then will turn off. Then when you start the engine it will turn on again and stay on when the engine's running.

Does it cycle +12v on/off when you turn the key on?

The only other thing I can think of to check is that the wire is pinned correctly. The wire should go to pin 9 on the red pcm connector.

Yes, 12v will stay on for a few seconds, but then go away when turn key to on position. Although, I will trace back to connector and verify that it is connected to the right connector pin. Is there any other pin that could be connected to wrong source or not connected at all that could be causing the fuel pump ciruit not to work (missing ground/12v source)?
 

350ss

New Member
Nov 13, 2008
4
0
0
Not really. It sounds like you said, it's just not activating the relay which could happen if the voltage drops below 12v which doesn't make sense to me. I have my pcm at the front of the car on the driver's side and the relay for the fuel pump at the back of the car on the passenger side and it doesn't have any problems switching the relay on.
 

MalibuRacing.com Gear

Stickers & Shirts!!