Car Wont Turnover

[R33silverS2]

Hey recently i had a Bosch 040 and new oxy sensor fitted to my car as both of my old ones were stuffed. Now after the Bosch went in the car either cranks for a lot longer before the engine starts or it wont turn over at all and you need to pump the accel pedal to start it. Anyone got any suggestions as to the cause of this? Obviously its to do with the new pump but anyone know why. Once the car is going it runs fine.

Cheers

[double overhead sun visors]

Yeh could be related, or may be not. Check your earth cable linkage from the engine & make sure it's all tight & in good nic.

[R33silverS2]

which cable is that? sorry got no idea what the earch cable looks like.

[BH_SLO32]

which cable is that? sorry got no idea what the earch cable looks like.

My experience with the bosch fuel pumps is the same. The pumps don't hold the fuel pressure once switched off due to backflow through the pump. This results in a longer priming period once the car has been sitting for a while hence the cranking required.

This is probably due to the clearances on these pumps which aren't like the stock units or the walbros which hold system pressure well. I installed a non-return valve in the delivery line of my previous car but it didn't improve things. My current skyline runs a walbro which I am very happy with. Functions better than stock pump IMO.

Hope this helps

[R33silverS2]

My experience with the bosch fuel pumps is the same. The pumps don't hold the fuel pressure once switched off due to backflow through the pump. This results in a longer priming period once the car has been sitting for a while hence the cranking required.

This is probably due to the clearances on these pumps which aren't like the stock units or the walbros which hold system pressure well. I installed a non-return valve in the delivery line of my previous car but it didn't improve things. My current skyline runs a walbro which I am very happy with. Functions better than stock pump IMO.

Hope this helps

So what your saying it that it is the pump and that is just how it is? Sometimes it just cranks and cranks and wont start but then when you turn it over again it will start.

[justin911]

ive got the same pump and mine doesnt do that, same with 1000's of other ppl.

So what your saying it that it is the pump and that is just how it is? Sometimes it just cranks and cranks and wont start but then when you turn it over again it will start.

[R33silverS2]

ive got the same pump and mine doesnt do that, same with 1000's of other ppl.

This is doin my head in.