Ever since installing the Walbro hi-pressure fuel pump in my 92 Camaro, the car has been hard to start on the FIRST time (after it has sat for 10 hours or so), but every subsequent start up (like running to the grocery store or gas station, etc) it starts up like a champ.

By hard start, I mean, it takes 2 seconds longer to crank than when it used to always instantly start up as soon as I turn the key.

What could the problem be ??

Also, I replaced the gas cap at the same time, but threw the old cap away..

 

If the new pump has a leaking check ball to hold in the fuel pressure the fuel system will lose its "prime". So the extra two seconds crank time is the system "repriming".

 

Would it be a bad thing to ALSO have a vented cap - I was not quite sure if it should be a vented gas cap or not... ?

 

Vented gas cap wouldnt cause the symptom you describe. It could cause a problem with your evap system thou.

 

Try lettting the system prime first to make sure it;s priming right. Instead of just putting the key in and starting the car...turn it to acc for a second and listen for the fuel pump to prime.

 

I did try that...so I wait overnight (10 hrs)
Get in car, put key to on, but do not start...

The Walbro makes it's usual loud noise... I hear it whining away..I've let it whine for a full minute... then I start car and chug chug chug (2 seconds) then, vroom, it starts up.

After that, I go anywhere else (gas station, grocery store) and whenever I return, it starts up like a champ instantaneously...

Could my brand new Walbro have a bad check valve inside it already? Man, what a pain to replace again... I wish it were something else. Can I have a bad vent line ? There's this diaphram thingy on the 4th vent line.... (1. fuel 2. fuel return 3. vent to tank? 4. diaphram thingy that you can blow through and it takes pressure before it opens) (Car is a 92 Camaro)

 

when u turn the key to acc i thought the pump was only suposed to pribe for a couple seconds? atleast on my car it does... it sounds like the pump isnt holding pressure.

 

any fuel pressure readings?