pgudge

Hi,

Long story short, about 2 months back had a bump, front end damage, had repairs done, all good, so I though. They had the car for about 3 weeks. Battery checked and working perfectly fine (Motosave checked)

Since I've had the car (7 years), its started every time, everyday without fail. When I now try to start the car I don't hear it priming, and the car won't start.

Turning off the engine and back on eventually it primes and the car starts fine, this can sometime take 1 minute, but mostly from 5-10 minutes until it primes.

Could it be the fuel pump on its way out, or something electrical, or even bump related?

Thanks for any info.

PaulG.

stevie turbo

iTrader: (12)

hi mate replace the fuel pump relay cheapest and most obviouse thing,if that dont work change fuel pump.

r1c

iTrader: (9)

Do you have access to a multi meter?
Don't start guessing and changing things? It's wasting money!

pgudge

Yeah, should have one in a box somewhere is there some sort of guide for testing if its getting power?

Thanks!

r1c

iTrader: (9)

You should have with the ignition on, 2 pins with battery voltage on, a switched earth from the ecu. The other wire goes to the fuel pump. If you can work out which on is the pump wire bridge it with one of the power wires. This should make your pump run. If all is ok then swap the relay for another and try again.

stevie turbo

iTrader: (12)

changing a 10 yr old relay at a very small cost i wouldnt say a waste of money i would say preventative maintanace but the other fella is right check power supplies etc

pgudge

Thanks everyone. Well I still ain't got this fixed (mainly because I haven't taken it anywhere yet)

I have been trying different things over the last month and can now get the car to start first time, but only if I leave the car to run after parking up for the day/night. If I drive to work, and leave the car running for about 2 mins, then turn off the engine, when I start it again round 6pm it primes and starts first time.

If I do leave it for over 2/3 days then it does start again (even after leaving to run).

If I pull up and turn the engine straight off, after 30 mins or so it doesn't prime straight away!

Does that help anyone remotely in identifying the issue?

Thanks!

ALi-B

iTrader: (1)

I had a similar issue on a BMW....turned out to be the fuel pressure regulator leaking back through the fuel return line. Would start cold, would never start first time hot (needed 8 seconds of cranking minimum, or cycle the ignition switch on/off three or four times ). It was also random, somtimes it was ok, somtimes it wasn't, I guess this was bacuse the regulator was sticky so would somtimes worked ok and sometimes would stick open.

Fuel pressure guage on the fuel rail when it was playing up quickly shows if its leaking down or not, as it should hold pressure when its all turned off. If it doesn't hold pressure, there is a leak either in the pipework, faulty regulator or the non-return valve in the pump/tank assembly. The regulator (and return lines) can be checked by clamping the return line and observing if there is any difference in the pressure drop.

Interesting thing on the BMW was that it would actually start and run ok with barely 1psi of fuel pressure!!!

It never stumbled, misfired or coughed, it always started on all six cylinders perfectly with next to no fuel pressure, then after a few seconds the fuel pump would prime and it would jump up to 55psi, but no change in engine running was observed. I suspect the reason why it always seemed to start ok when cold was that the injector duration was so large that there was enough fuel dribbling out of them to fire up the engine, and/or the regulator would eventually unjam and close.