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Discussion Starter #1
Hi all,

Car has been running fine since my red cog issues a year ago (long drama) - until today.

I pulled out of my drive way and sat at an intersection waiting for 1-2 minutes for traffic to clear. Once it did, I pulled out and it stalled! Turned it off then started up again and guaranteed within 5-6 seconds, the revs would drop to 500rpm, car would chug/shake then it'll stall. No CEL/errors, and all electrics still running. Half a tank of fuel. Car has been driven daily.

Because I was literally 15 metres from my driveway, I managed to reverse back by way of starting up then quickly reversing then letting it stall within 6 seconds (guaranteed), then rinse and repeat. Took around 10 stall/restarts before I managed to get back into my garage again. Again, there are no CEL's.

Have spoken briefly to my mechanic who advised me to pull out bottom of back seat and listen for the fuel pump to prime (right-hand side). I can just hear it priming but after 6 seconds when the car starts to chug/revs drop, the pump stops whirring. Once car stalls, I can hear the pump give out one last quick whirr.

Thoughts? I'll be getting the car towed to him tomorrow for him to run some tests to determine if it definitely is the pump or not. Pity there are no CEL's to pinpoint it a bit better...

Thanks in advance.
Linh
 

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Discussion Starter #2
Oh yea, car has 115,000km on it (71,400mi) and as far as I'm aware, the fuel pump has never been replaced before.

Additionally, a fortnight ago, the car went into reduced power mode out of the blue one morning when I gave it a bit more than normal (not redline) on a cold engine when pulling into traffic. Turned it off then started up again normally with no issues since then till now. May be related?
 

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Discussion Starter #3 (Edited)
<deleted - duplicate post>
 

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Discussion Starter #6
thanks for the tips - i'll have my mechanic check that stuff out.

today i had my local "roadside assistance" guy come around (pre-requisite before being able to book a tow truck) and he checked that just when the engine stalls/cuts out and the fuel pump stops, there is still positive electrical running to the pump itself. he also thinks its fuel pump too.

waiting for tow truck to arrive now to take it to my mechanic who would run a fuel pressure reg to really determine if its faulty.
 

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Discussion Starter #7
ok my mechanic doesn't think it's the fuel pump anymore. he reset a few things and now the car doesn't turn off after 6 seconds like before. however whilst monitoring it now, power to the fuel pump will cut in and out... so something else in the system from an electrical point of view i believe is telling it to stop. also at idle, he say its running at 6bar but it should be at 3bar?
 

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I have a direct fuel pressure gauge mounted on my car to monitor injector leak down on shut down. If I start to get a stuck injector, this will tell me. The fuel pressure goes to 90 psi when I shut the car off. If an injector is leaking it will drop in pressure. When the car starts with cold high idle, the fuel pressure is 90 psi. When it idles down to warm idle, the pressure drops back to 45 psi and stays there. I think in high demand, the second fuel pump kicks in and the pressure is back to 90. It is at 45 most of the time with normal driving. There is a one way check valve in the pump to trap this fuel pressure in the fuel line when you shut the car off. Mine will stay at 90 psi, static for 6 hours. So 3 bars and 6 bars are normal.
 

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Discussion Starter #9
thanks for the reply! i did find your thread about your fuel pressure gauge you mounted! so that 3-6bars is normal... i guess he's trying to work out really why the power to the pump periodically gets cut off. i havent spoken to him today yet and he was working on the car till late last night... hopefully he's found something new. he wants to avoid doing things like replacing parts all willy nilly without know categorically that it's busted.
 

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I have a direct fuel pressure gauge mounted on my car to monitor injector leak down on shut down. If I start to get a stuck injector, this will tell me. The fuel pressure goes to 90 psi when I shut the car off. If an injector is leaking it will drop in pressure. When the car starts with cold high idle, the fuel pressure is 90 psi. When it idles down to warm idle, the pressure drops back to 45 psi and stays there. I think in high demand, the second fuel pump kicks in and the pressure is back to 90. It is at 45 most of the time with normal driving. There is a one way check valve in the pump to trap this fuel pressure in the fuel line when you shut the car off. Mine will stay at 90 psi, static for 6 hours. So 3 bars and 6 bars are normal.
Can you share which gauge you used and how you installed it? Thanks
 

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Discussion Starter #13
thanks for the reply! i did find your thread about your fuel pressure gauge you mounted! so that 3-6bars is normal... i guess he's trying to work out really why the power to the pump periodically gets cut off. i havent spoken to him today yet and he was working on the car till late last night... hopefully he's found something new. he wants to avoid doing things like replacing parts all willy nilly without know categorically that it's busted.
now back to my actual problem :) hahaha still waiting on feedback from mechanic today... but thoughts on the above?
 

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Discussion Starter #14
OK mechanic definitely knows that it's the fuel pump. it got a bit technical for me and i lost track :( but i think it was something along the lines of, it will work for initial few seconds but after that because it's struggling, it's drawing extra current (or somewhere in the system is giving it extra current) to try and work harder to bring pressure up but because the pump is faulty. it then just gives up and it all shuts down (failsafe). this explains the fading lights at one point (cos of the extra current being pushed to the pump). he gave me more definitive evidence but errr bit too technical for me :(

going through warranty now to order new pump/filter so hopefully i wont have to update this thread again! wish me luck!
 
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