Crank but no fire first key turn, starts right up second key turn?

[dukeofchen]

I recall reading awhile ago that a few folks had issues with the radium kit and the included electrical connectors arcing and melting (causing intermittent or total failure.) Do you know if this was ever addressed? I'm planning to replace my pump in one way or another soon and would rather do the radium kit if all the kinks were worked out...

Interesting, I haven't personally heard about these issues when I bought the kit, but then again we had already lost M3F at that time.

I did notice when installing the new pump that the blue spade connector for the ground wire (the smaller of the two in the image below) did seem to be slightly looser when connected to the female end that runs from the original pump housing. The spade connector has an internal tab that you have to make sure mates to the other end, so after hooking the tab, squeezing the shit out of it with pliers, and applying the heat shrink I figured it would be solid enough. I could see someone messing up the electrical connections if they aren't careful, which might account for the failures. It's Step 17 in Radium's install instructions.

Either way, probably best to reach out to them directly. Would be very interested to see what they come back with if they are aware of the issue since I'm running the kit myself.

[duracellttu]

Have you considered replacing your ignition switch. I was having a similar issue a while back but was never able to find root cause. Ended up replacing my starter and ignition switch and haven’t had issues since.

[gabylonfive]

Interesting, I haven't personally heard about these issues when I bought the kit, but then again we had already lost M3F at that time.

I did notice when installing the new pump that the blue spade connector for the ground wire (the smaller of the two in the image below) did seem to be slightly looser when connected to the female end that runs from the original pump housing. The spade connector has an internal tab that you have to make sure mates to the other end, so after hooking the tab, squeezing the shit out of it with pliers, and applying the heat shrink I figured it would be solid enough. I could see someone messing up the electrical connections if they aren't careful, which might account for the failures. It's Step 17 in Radium's install instructions.

Either way, probably best to reach out to them directly. Would be very interested to see what they come back with if they are aware of the issue since I'm running the kit myself.

I think that spade connector is the one in question, except it's the hot lead (larger) one that ends up arcing and failing - here's the link of the article I initially saw the issue..looks like it was a follow-up article after putting the pump to use. I was pretty set on going with the setup until I saw it. Great write-up by Andrew @ Buildjournal:

https://thebuildjournal.com/news/you...-you-stranded/

[dukeofchen]

I think that spade connector is the one in question, except it's the hot lead (larger) one that ends up arcing and failing - here's the link of the article I initially saw the issue..looks like it was a follow-up article after putting the pump to use. I was pretty set on going with the setup until I saw it. Great write-up by Andrew @ Buildjournal:

https://thebuildjournal.com/news/you...-you-stranded/

😮 that is not comforting, perhaps I need to go in and solder mine as well...

[Maxhouse97]

Back to the fuel pump, glad to hear that it’s a easy swap. Do you think this symptom is a sign that it is wearing out? To me that’s another reason to go replace with new, as I mentioned I have a plan to incrementally do that as issues pop up so I can keep this car running well for a long time. It is also currently my daily, so I’d like to keep it reliable.

[eacmen]

Back to the fuel pump, glad to hear that it’s a easy swap. Do you think this symptom is a sign that it is wearing out? To me that’s another reason to go replace with new, as I mentioned I have a plan to incrementally do that as issues pop up so I can keep this car running well for a long time. It is also currently my daily, so I’d like to keep it reliable.

Try turning the ignition to II but don't crank it for a few seconds. If the no-start issue goes away then it's likely fueling related. If it persists then look elsewhere.

Basically if the fuel pump is going out it will take longer to build pressure and cause the no start.


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[Maxhouse97]

Yes that’s what happens, if I delay slightly I have no issues. So am convinced it’s the fuel pump. Even if I’m wrong I suspect I would need to replace it anyways with my age/mileage.

[eacmen]

Yes that’s what happens, if I delay slightly I have no issues. So am convinced it’s the fuel pump. Even if I’m wrong I suspect I would need to replace it anyways with my age/mileage.

I would switch/inspect fuel filter first. Something you should do anyway if it hasn't been done in quite some time.

But I think you're right. likely the pump.


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[ethan]

Try turning the ignition to II but don't crank it for a few seconds. If the no-start issue goes away then it's likely fueling related. If it persists then look elsewhere.

Basically if the fuel pump is going out it will take longer to build pressure and cause the no start.


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Not necessarily. If it's a warm start, the car's expecting there to be pressure in the system already and in my experience hearing the pump prime isn't enough. A bad check valve and/or a leaking PTFE submersible tube are common causes for this issue even when the fuel pump is in good working order.

[ethan]

If this only occurs on warm starts. Then it's your fuel pressure check valve. The fuel pump doesn't always prime on warm starts so if your check valve is bad then all the pressure bleeds off. On cold starts your pump will prime every time (audible).

Can confirm a bad check valve will exhibit this behavior, but I've also found that the factory fuel-safe/submersible tubing between the pump and the housing likes to leak at the junctions allowing pressure to escape. This is particularly common in fuel pump swaps when reusing the original tube. Radium sells new replacements and that has cured the problem for me twice in two separate E46 M3s.

[eacmen]

Not necessarily. If it's a warm start, the car's expecting there to be pressure in the system already and in my experience hearing the pump prime isn't enough. A bad check valve and/or a leaking PTFE submersible tube are common causes for this issue even when the fuel pump is in good working order.

Agreed. I think the OP is experiencing cold start issues though.


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[sapote]

This could also be a symptom of a starter motor going bad

why starter? It cranked ok except that the engine did not fire up?

[sapote]

You can also disconnect the fuel pump fuse and let the engine consume the fuel in the fuel lines.

This method could burn valves due to too lean fuel.

[sapote]

Yes fuel pump makes sense. I am trying to start it right away like normal. Thanks.

why not try to prime the pump a few times before cranking, just to verify if it's due to fuel pressure from an old weak pump or leaky check valve? It's a good idea to let the pump priming and building up pressure before cranking -- save the starter in the long run.

[ATB88]

Question about check valve: this is a part of the fuel pump assembly, yes? If I've recently replaced my whole fuel pump assembly, I should be able to rule out the check valve entirely, yes?? Is there a chance that my check valve on my new pump just failed really early??? It would be really nice if this was the answer to my problem.