Slow start 5+ seconds of cranking

[nomansland92]

I've had this problem for a while now but its been getting worse so time to fix it before im stuck in a parking lot and 11 o'clock at night, However i've noticed if i leave the car out for the night it starts right up more often. If i leave it in or if the engine is still warm i get the problem a lot more often it seams to help if the hold the throttle wide open while cranking also. So why would it start better in the cold? Today i went to start it which its been in the garage and not started for at least 4 day and i couldn't get it to start. i jumped the fuel pump to test and and it worked. switched relay and no fix pulled return line of and had fuel and pressure, could it be electrical, or possibibly its not holding pressure in the line like if there is a check valve in the line. So what should be the next thing to look into here any help would be nice
Thanks, Stevan

[Adrian_Visser]

If it helps to floor it when cranking you are most likely getting too much fuel and the engine is flooding.

Stating your year and model would be a start.

[nomansland92]

ha ya sorry about that but its a 88' 325ix. i think the next test is to let it sit to where it normally messes up then pull the return line off the regulator and see if there is pressure right there cause maybe its bleeding back into the tank, just a thought though

[Adrian_Visser]

Yeah that is totally possible. There is a check valve on the outlet of the pump that is supposed to maintain pressure which sometimes fails, but I wouldn't suspect it so much if the problem you are having is warm start related.

[nomansland92]

Ya today i had it out all day and drove it like 10 different times and started right up pulled it in to was all the salt off and sure enough give me a slow start but it was like 4 seconds of cranking because it wasn't that warm yet

[Flash635]

Do those cars have an in tank pump as well as an external one?

[jlevie]

The first thing I'd do would be to have a smoke test run on the intake and fix the leaks that test uncovers. Then I'd measure the pressure in the fuel while the car is having a slow start and check the ECT sensor to see if it is good. If I haven't found/fixed the problem by this point I'd pull the injectors, pressurize the fuel rail and see if they drip.