Injector electrics?

[Brian28]

Car is a facelift 320i. I stuck a new head on the car last weekend, got everything up and running fine, swapped the air box for a K&N type open filter (race car), everything still ran Ok. Didn't start it for a couple of days as I had a few other things to tidy up/weight to remove etc, nothing mechanical/to do with the engine electrics. Yesterday it wouldn't start when I wanted to move it. The engine is firing and will almost start, just catches a bit then dies again. The fuel pump is definitely working and there is a good petrol supply, all fuses good, it is firing Ok, I've stuck in a new set of plugs, swapped the ECU, swapped the relays on the bulkhead, all bits swapped for ones I know are working from a different car, still the same. I've double checked the cam timing in case the belt had jumped a tooth, but marks line up perfectly. (Sounds a bit like it may have been marginal compression due to belt, but compression is fine).

So what I'm left with by process of elimination is that the petrol is getting to the fuel rail, but the injectors aren't injecting as they should. This is what it souds like as well, trying to start a car that has run out of petrol. So, which of the bulkhead relays are for the injectors. Which pin sockets (with the relay removed) should have power with the ignition on? Which fuses are for the injectors? Anything else located elsewhere other than the three bulkhead relays and the fuse box?

Thanks
Brian

[Turbo-Brown]

Wouldn't just be a faulty Fuel Pressure Regulator that's not giving adequate pressure would it?

[Ant]

OK before you go mad and pull all the wiring apart looking for a fault....

pull the fuel pump fuse out( refer to main site ) crank the engine with the throttle wide open for 20 seconds, replace fuel pump fuse and see what happens.... it should fire up , sounds flooded to me, alternative to above is pull the ICV from the bellows, crank away and once fired up, stuff the ICV back into the hole.

HTH

Alex.. any speeding tickets yet M8 ?

[Martinaston]

Is the injector wiring plugged back in correctly ?
(the plug that sits way down under the inlet manifold and connects the injectors to the main part of the engine loom)

[Kamaloff]

You'd know a lot more about the engine if you removed the spark plugs and examined them. As you well know, plugs can give vital information about the condition of the engine.

[Brian28]

Thanks for the input guys. When I finished building it all back after stripping down to check timing marks etc, it started. Wasn't flooding (left overnight with no plugs in so anything would have evaporated) then new plugs in the morning, basically I didn't find anything wrong with it so haven't really "fixed" anything. My pet theory is a loose electrical connection somewhere (not in the obvious places as they've all been checked) that is making contact now. Hope not, first race at Brands Sunday week and I'd really like to hope for a reliable car!

Cheers
Brian

[Templ8e30]

Thanks for the input guys. When I finished building it all back after stripping down to check timing marks etc, it started. Wasn't flooding (left overnight with no plugs in so anything would have evaporated) then new plugs in the morning, basically I didn't find anything wrong with it so haven't really "fixed" anything. My pet theory is a loose electrical connection somewhere (not in the obvious places as they've all been checked) that is making contact now. Hope not, first race at Brands Sunday week and I'd really like to hope for a reliable car!

Cheers
Brian

So the problem started after fitting new plugs in the morning ?. Have you tried the old plugs to see if that's the problem ?.

I serviced the wifes 316i years ago and it ran like a bag of spanners, when I refitted the old plugs it ran fine. The new plugs were the correct Bosch fitment but it hated them. I bought NGK's and it ran fine again. Sh!ite plugs !.

Cheers,

Iain T

[Brian28]

Nope Iain, the new plugs were an attempt at a cure after it wouldn't start on the old ones the day before. Cheers anyhow

Brian