Won't start after radiator upper hose change and AFM clean

[hpxxhan]

Hi Folks, I just posted the pics of my newly acquired 6er but today I have my first problem.. haha.. what a joy.. Anyhow long story short, i woke up this morning... i went over the engine and tighten all the little clips along the intake.. and then moved on to removing the air filter, blow it with compressed air since it still looks clean.. and then use the electrical connector cleaner spray and spray the flap area as well as where the flap is hinged. I did push the AFM flap a little bit with hand to open up the hinge area and spray some clears. Waited until all the clear evaporates.. and then reattached the air filter cover and tighten things up.

Then I want on to check the coolant lines since I've been loosing a bit of coolant. Found a split on the upper hose which connects the radiator to the thermostat housing. Replaced it with the new hose and some coolant spill but it's mainly onto the fan shroud and a bit on alternator. Wiped everything and top up the coolant. Then tried starting it and it just kept on cranking and won't start. I haven't checked anything yet but I can't think of anything that i might have done wrong to cause a no start.

I'll try and pull the plug to check the spark and maybe loosen one of the fuel lines to check and see if there's fuel? Anyhow, i'll browse through the forum as well but in case if you gents have some more pointers. Help ! :)

[hpxxhan]

Ok here are a couple of updates on what I've checked.

1. Pulled a plug and checked for spark. There is spark.
2. Pulled the fuel line into the fuel rail and there's zero fuel coming in. Turned to "ON" and no fuel. Cranked the car and no fuel. So looks like fuel is missing in this equation.

Couple of things I noticed when pulling the fuel return line at the regulator. The hose that i pulled for replacement is right next to the fuel regulator and #1 injector (? the one at the very front). When I pulled the radiator, i tried my best not to spill since I disconnect first on the radiator side and let the water out from the lone before i pulled the line from thermostat housing. But there may still be some water that might have gotten on to one of those and shorted things out?

Also after changing the coolant line and start for the first time it turns and all of a sudden everything went dark, not dash lights nothing. Only after I jumped the battery it lights up again but won't start anymore. So that's where i'm at. Any thought is appreciated.


Thanks,
Han

[hpxxhan]

One more update. I also checked the fuses for fuel pump etc and all the fuses are ok. Am I suppose to hear the fuel pump run when i turn on the key to "ON"? Right now I'm not hearing anything when i turn the key to "ON". On my other cars I can always hear the pump run.

So next step is to check the fuel filter and the pump itself.


Thanks,
Han

[hpxxhan]

Ok I found the root cause. It was the fuel pump relay. It was a freak coincidence that it died after the last run before I do the house keeping work under the hood. I swapped it with the horn relay for now and car runs good now. I put the failed one in horn relay location just to check and yep it's dead.. no horn.

Funny thing is I can't find any relays at the dealers around me. So I'll just have to wait for my online order and I'll try and junk yard dive tomorrow to see if i can get a hold of a couple. Anyhow just logging it here so that someone like me can use this info. Fun experience :)

[Pod]

Well done and welcome to the madness! I was going to suggest the pump as I was reading your post, then got to the end

[Brucey]

FWIW the fuel pump only runs (if you have motronic) when the engine is either cranking or running. It does not run when the ignition is on and the engine is not turning.

cheers

[hpxxhan]

Thank you gents. Thanks to the wealth of info on this site I was able to check things off quite quickly. Thanks to this flakey relay, I think the battery might have bit the dust.. i'm reconditioning with ctek and we shall see.. Now I'm just going to continue with routine service items.. just changed the plugs today and running like a champ. No more knocking and just maybe a hint at full throttle in some gears but i'll live. Oil change and air filter next and maybe fuel filters etc. And next big item is AC.. need to check. Compressor seems to engage but no cold air so i think there's a leak. Anyhow, slowly.. but surely it'll get there :).