87 22re. Ever since I have owned this 4Runner it has had to crank longer to start than I would like after it sits overnight. When I turn the key on 'on' I get no fuel pump sound. Using 4Crawler and FSM info I jumpered the diag box and the fuel pump starts. It starts faster when the pump is jumpered but still not immediately as it does when it has not been sitting. I changed out the AFM and the Circuit Opening relay (even though the Circuit Opening relay and the AFM both bench tested ok) from my last truck that did not exhibit this problem and there is no change... the Main relay is in the circuit also but if the main relay was bad the pump would not run even with the jumper, correct? Kind of baffled ....any suggestions?

Normally no fuel pump running w/ ignition on, as it takes air flowing through the AFM to keep the CO relay on. And yes, if main relay or EFI fuse were out, the fuel pump not running would be the least of your problems <img src="/forums/images/graemlins/smile.gif" alt="" />

Check the cold start injector and CSI timer switch, maybe those are not working right, after all that is what helps with cold starts.

Thanks Roger. This engine (with the cs injector, switch, etc) was in the old parted out truck and it started fine at all times. But I will check those anyways. I guess I could just have a small leak that is bleeding down the pressure overnight, correct? But I smell or see no evidence of that. I would have to fabricate something to get a pressure gauge on there right?

I put a fuel pressure sender in the back end of the fuel rail:
http://www.4crawler.com/4x4/CheapTricks/Gauges/index.shtml#Fuel/AirPressureGauge

It's possible that the pressure of the fuel, in the rail, at the injectors is bleeding off overnight. One thing to do is to jump the fuel test connector, and the next morning, turn your key to "on", letting the pump run, for about 10 to 15 seconds, building the pressure back up, THEN starting the truck.

What would fix this? New rubber o-rings on the injectors?
Where would it be leaking, just curious.

Anybody know what causes the pressure loss overnight in the injector rail? I thought this forum was to help people with their Toyota pickups, share the knowledge and experience, and discuss our common interests. I guess I can understand if nobody is able to or wants to help me out.
Thank you.

Relax. Nobody is ignoring you. We're here to help, but were only human, and posts can get overlooked.

A fuel leak could be anywhere. Rusty lines, cracked rubber hose, leaking injector orings, loose fitting somewhere.

But my money is, like Roger said, something in the cold start injector system. You said you were going to check the CSI system...did you? How? Did you probe the connectors at the ECU and measure resistance?

I had the EXACT same problem after a timing belt install. Took forever to start when cold, cranking and cranking and cranking. Worked fine before??? Well turned out the wire going to the ECU temp sensor was messed up, one of the wires in the plug was pulled out. No way to tell just by looking at it from the outside as it was firmly plugged in, but as soon as I probed the ECU I realized I had an open circuit.

There is an FSM sticky'ed at the top of this forum. Should have all the info you need to get a wiring diagram and instructions for your vehicle.

Thanks Adam - I am interested in this because my truck doesn't start up right away, you know in few revs of the starter. The 94 I owned in the past whcih was stock and low miles started right up. In fact it seemed to jump to running state when the ignition was turned on. This 93, which I rebuilt and am going to tear into again seems have to crank alot to get started. So, I was wondering where a leak could be. I didn't get the injectors calibrated last time becuase I don't think I had that info about it. This time that will be par for the course. Having read all of you peoples posts for the past 5 or six years. And of course, it could be another problem, but it sure acts like what Stace was talking about. Sorry I haven't tried the jump yet. Appreciate the response. Don't shoot me but I do have a fsm for the year.

I have made my own adapter for a standard fuel pressure guage. All I did was cut off and un-bolt a fuel line from a fuel rail on a 4cyl 91 camry (easier to find and I dont feel as bad cutting them up). I hose clamped the line to the guage and connected to the fuel filter to get the pressure reading there. I also unbolted and cut in half a cold start injector line from the same camry, bolted that to my fuel rail and hose clamped that to the guage to get a fuel rail reading. I figure the cold start reading might be a bit lower than actual rail pressure due to the small diameter and length of the line, but the pressures I read were almost exactly what the F.S.M specified.