Start problem on a s5 fc
 

Hello everyone, I know that for a fuel injector car u not suppose to pump the gas when starting. But for my car it will crank but won't start till you actually pumping the gas petal while cranking it. For cold start u only need to pump 3 to 4 time for it to start, but once it warm up sometime take u 5 to 10 minutes to start it. Is this the problems with the fuel pump am having?

Does the exhaust smoke any after starting? You might have leaky injectors or you could have clogged primary injectors. The water thermosensor could be causing problems. You could also have low fuel pressure or a dirty fuel filter or fuel sock in the gas tank. The FPR could also be problematic.

And your engine might have low compression.

I agree, need to check compression before replacing a bunch of parts!

Ty for the Fast reply, i will take to MAZDA for test when i have times

But i don't think it have anything to do with the compession. Cause I notice the engine will die if I hit a bump or on a uneven surface. Hope that info will shead new light to my problems.

Sounds like a grounding problem. There are a group of ground wires below and to the side of the trailing coil against the fender well. One of these wires is a ground for the main relay. If it is not grounded properly then that could cause the relay to open up and the car would die. You can test this hypothesis by bypassing the relay. To do this on your car you would jumper the White/Red wire to the Black/Yellow wire and the White/Blue wire to the Black/White wire at the relay. Bypassing the relay could cause the battery to drain some over time so be aware of this.

Thanks satch. One more question would that effect the starter problems I mention above or that just another problems that I have?

Most likely another problem.