Recently rebuilt 2nd gen suddenly won't start - where to begin?
 

Okay, here's the deal -

I'm driving an S4 (87) n/a, stock for all practical purposes, got about 25k miles on a rebuilt engine, and at the same time got new fuel pump, new injectors, new ignition coils, etc.

I drove the car two days ago, and it ran 100% normal. Tried to start it today, and it'll sit there and crank and crank but won't actually fire up so I think I'm either not getting fuel or not getting a spark.

What's a good starting point as far as things to test?


**I should note, the guy who rebuilt my engine installed a kill switch (pretty sure it's for the fuel injectors, in case the engine floods)

Did you try "flood" starting it, put the pedal in the floor and crank it? See if it turns over then.

This does not work for any S4 vehicle.


-Ted

Oops, works on my S5. I forgot. Pull the plugs and crank for 15 seconds, reinstall plugs and see if it starts up.

Shouldn't the tach 'bounce' if it is getting spark?

I forget.

Yes, but that only indicates a specific coil is firing.

Pull the plug wires and put a screw driver to the tip of them and see if there is a spark arcing.
If there is, pull your two leading plugs, and yer EGI fuse and turn it over and blow all the gas out of it. Squirt a little motor oil in there while yer at it.
Try that.

Thanks for jumping in here!

What will that do? If it's a cure for flooding, the kill switch works for that. If it's supposed to cute something else, lemme know and I'll try it!

My tach 'bounced' all of once in the whole time I was trying... so it does sound like I may not be getting spark. What would I do to test/confirm this?

As in, screwdriver in one hand, and one plug wire end in the other, right? how far apart should I hold them?

If there's no spark arcing, that means my trailing coil is not functioning, then, right?

I typically just leave a plug in the end of the wire and ground it, have a helping hand to turn it over, and while that is going on you can observe whether or not there is spark. Screwdriver works too, just a little cumbersome to me.

This.
But, having been zapped before, I'm now paranoid and I use a set of pliers with an insulated handle to hold the plug by the boot on the wire.

Watch the tach needle while trying to start the engine. IF the needle makes small movements that tells you a lot. It tells you that the ENGINE fuse, both EGI fuse are all good and that the main relay is pulling in.

Engine will not start with a blown EGI fuse(s), engine fuse, period.

IF the needle does make movements try deflooding it by the usual methods. I assume you don't have a blown apex seal when saying this and you have gas in the tank and there is no fuel cut switch in the OFF position.

EDIT: And or ...........put a jumper in the fuel pump check connector and the key put to ON. The fuel pump should be heard running. If not.......too bad, something is amiss.

Pulling the fuse does essentially the same thing your fuel cut switch does. Putting oil in the engine helps build compression if it's been flooded.

I'll check the EGI fuse. -checked and all fuses with EGI in the title are fine.

Tach is making the tiniest of bounces once each time I start the ignition, then nothing.


**engine isn't flooded, there's practically no way an apex seal is blown, etc. - Fred's assumptions are all fair.

Where is the fuel pump check connector? Not coming up with that one easily in the Haynes manual