Need help testing fuel pump relay set

[wikkid]

Here's the electrical current path I believe I need to check out, since my fuel pump will run when triggered manually by the AFM flap, but it will not run when cranking (ignition key in "start" position):
Current from ignition switch "start", to
terminal 86a, to
fuel pump relay coil, to
terminal 85, to
ECU, to
ground 7.

Here is what should be happening, according to the electrical manual:
the fuel pump relay closes, so then current runs thru C17 (from battery), through inline fuse, through relay contacts, through terminal 88d of the relay set, to fuel pump, and to ground 5.

Just because I can paraphrase that out of the electrical manual doesn't mean I know how to get in there and check if the relay is ok, or if there's a bad ground or something like that. I just know that the fuel pump is new and operates just fine when I open the AFM flap, but it does not run (as it should) when I turn the ignition to start.

Can anyone hold my hand on this one, or point me to some testing procedure instructions? I could always spring for a new $100 dual relay and hope that it works, but I'd like to be sure that's what it is before I buy one.

[divace73]

Hi Wikkid

Are you saying the fuel pump will work when the ignition is on and you open the AFM door, but won’t do it when you move the key to the start position (turning the engine over)?

It should only run once ignition is on and the AFM door opens, (it is a safely measure that if your engine stopped, fuel also stops), I am assuming the following, that your AFM is connect up to the correct plumbing and the system is sealed from the AFM to the intake manifold and your double relay is working?

Once you start cranking your engine the vacuum from you engine will suck the flap open (a switch inside your AFM engages). If you have any air leaks from the AFM to the throttle body, this could stop you AFM door from being sucked open.
OR Could it be running but cannot hear it due to the engine noise at the same time?
If your car won’t kick over you may actually have a spark problem?

I would make sure all the plumbing is complete and try and swap your double relay for another to ensure that it is not the problem, I started having issues with my double relay where one of the relays would get into a 'stuck position after it was energised. They also develop dry joints after some time. The $100 (actually more like $150 here in Oz) odd dollars for a new one saved me a lot of headache.

If you PM me I can send some PDF's that may help?
cheerd David

[So Cal Mark]

is your intake boot attached so that the flap moves when cranking?

[wikkid]

I may have been barking up the wrong tree with the relay. I opened up the AFM top, made sure the sweeper was making good contact, also loosened the big coil spring in there by 5 notches on the cog, and watched it while the system was all closed up (intake on tightly, all hose clamps tight) and a friend cranked the ignition. The sweeper and the little silver arm that pushes the copper contact strip away from its contact jumped back and forth with each turn-over of the engine as it tried to start - right in rhythm with the engine drawing air in past the flap.
The pump now gets a good signal, and comes on as it should, so the relay must be ok, handling the ignition and AFM signals correctly.
The fuel pressure at the CSI hose is 35 psi at ignition "run" position (engine not running, because, of course, it has not yet started), and with AFM flap held open.
I got 3.4 ohms at the CSI contacts. I am going to pull it and see how well it squirts. I'm next going to attack the AAV and the other cold-start widgets, the CTS and the TTS.

It also sounds dumb to do in this sequence, but I had better have a look at the static timing. I just hadn't looked yet, because I began chasing the non-starting issue with a bad fuel pump, and have been chasing EFI diagnostics up to now. Time to also go back to basics, unless someone has a better suggestion.

Note: the above post is a bit of a repeat of yesterday's news at this thread. Sorry for the redundancy.

[narfire]

I think you have made the best decision.. check the timing now you have fuel to the rail.
We'll expect a post tonight saying it's running like a good swiss clock
Chris