OldLaredo

So I posted about this in chat but it fell dead. So im trying here.
Ive got a 92 laredo that takes way too many cranks on a cold start and is otherwise finicky on start up. When I come out of a store sometimes it will fire up right away then shut off. Then its fine.
It seems like priming it on cold starts helps.
Am I thinking fuel pump, leaky injectors? Brand new interstate in it. And just replaced leaky fuel pressure regulator

Pelican

Could be leaky injectors but likely faulty check valve. If it turns out to be the valve, adding an external check valve on the '92 is inexpensive and easy. And you can replace the fuel filter at the same time if you haven't done so lately.

I did this on my '93 some years ago, it fires up first time every time, and holds pressure for days.

One other thing, starting and immediately dying can be a failing ballast resistor on the driver's side inner fender. You can bypass this by pulling the two leads off and clamping them together. The resistor serves no purpose except to theoretically quiet the fuel pump after the motor starts.

RTorrez1

You can try the poor mans prime. Turn the key to the on position with out starting it. Do the for 2 or 3 time then try to start it on the next try. If it start faster it would be like Pelican said you have a bad check valve (anti-drain back valve). Give that a try and let us know if it helps.

OldLaredo

Sorry, forgot to mention, it does seem to help to prime it like that. Also I hear the pump kick on every time, so I know it's at least doing something. I might have to look into this check valve idea. I'll do some forum searching myself, but any input on the specific valve to get?

OldLaredo

Hey, thanks for the help guys. I think I'll avoid cutting into the line at all, even though the check valve thing would probably solve my issue straight away. Down the road I think I'll drop the tank, clean it, and put in a new fuel pump assembly (Pretty sure this one is original, so 243k on it).
For now I'll just prime it since the only real issue seems to be fuel draining back into the tank.

RTorrez1

Not a problem. It would be the anti-drain back valve. I'm not sure for your year if the valve is on the fuel rail or on the fuel pump in the tank. I have read on this forum that some have put a check valve in line and not replace the one on the fuel pump but I have never done it myself I I really can't say how good it works.

Pelican

Works great as I mentioned above. As long as we are on the subject, I got the check valve from ebay for ~$35 IIRC. It's been about 5 years but if I find the source, I wiil post up later. I'm sure I followed some forum write-up. The valve just splices into the rubber line aft of the fuel filter.

I can't argue with changing the entire fuel pump assembly but I was not in the mood to get involved in playing with the tank when I had my problem.

Pelican

I paid $16.50 in May 2009 for the check valve.

I believe this is the eBay site: http://www.ebay.com/sch/i.html?_nkw=check+valve+fuel

I seem to have lost my eBay paperwork and am not sure what the fuel line diam is (I'm guessing 3/8") but that is easy enough to check if you decide to go this route.