DOT3

I thought the newer Toyotas have a slight delay on start to allow the oil pump pressure to build. This is to prevent wear on startup. Mine takes maybe 2 seconds too and my old older truck will start almost instantly.

bamachem

my 99 takes about 2 seconds as well.

it has new plugs, pcv, fuel filter, clean air filter, clean maf, clean throttle body, and clean intake and injectors thanks to seafoam.

it's always been that way. sometimes if it's good and warm and is only shut off for a few seconds, then it will fire right up, but usually, it takes a couple seconds. nature of the beast i guess.

MTL_4runner

I don't see any rationale behind what you are saying the toyota engineers designed (not that you are incorrect).
Why would it be beneficial to only have the fuel pump build pressure while cranking, not in the "on" position?

.....the lines are designed for full pressure so the pump should shut off once that pressure is achieved.
Have you checked the rail to watch fuel pressure at startup?
Is there a fuel pressure sensor that can be tapped into (I have not seen one in OBD, but it may be unaccessable).

ken.vs.ryu

battery cables?

KGnagey

I would guess that a couple seconds cranking when cold is normal. Mine does turn over quickly once warm but after sitting over night it takes longer, especially if its cold out side. Maybe the oil viscosity? I might just be more aware of the cranking time after the two episodes I had where it did not start.

When I pulled the NGK plugs I checked the gaps and they were very tight .10 to .20. The manual says the gap should be .44. After I replaced the plugs with new NGK's gapped properly, my MPG increased but I still have about the same cold cranking time. I just don't want to be stuck one day with it not starting again. Again, I only have 42K miles. I will be checking cables this weekend and changing the belts once it warms up a bit here.

Thanks for the replies

KGnagey

FYI...

Found an older thread regarding this same subject.

https://www.yotatech.com/forums/show...9&page=2&pp=25

At least I feel better knowing this is more common and I'm not the only one with the same symptoms.

Jay

As the system is designed to retain sufficent pressure while the engine is off to restart the vehicle, the fuel pump can almost instantly regain full pressure in the fuel line as soon as the engine control unit detects an rpm signal.

If the engine is not running or cranking, having the fuel pump runing would pose as a serious danger in the event of an accident. :fireman:

Fuel pumps dont shut off when pressure is achieved. There is no onboard fuel pressure sensor. There is a fuel pressure regulator located either on the fuel rail or on newer models in the tank itself. The regulator dumps extra fuel volume back to the fuel tank as needed. It is critical to maintain a constant fuel pressure as the injector spray duration is programmed for a fixed pressure. Injector duration is increased for enrichment, and decreased to lean the air/fuel ratio out.

I think this may be directed to the original poster, but I have performed this test on many occasions on the 3.4L specifically to address this concern. I connect a fuel pressure gauge to the engine, allow it to pressurize and then shut off the engine. I allow the vehicle to sit for the day, or overnight. Typically when running, the fuel pressure is approx 45psi. I would need to consult the repair manual but I believe the system should retain 40psi in this time span. But typically if the vehicle IS loosing fuel pressure over time while off, by the time I come in the next day the guage reads next to 0psi. So its pretty easy to know if there is a problem. Anyone ever have to replace thier "pulsation damper" on thier 3.0L's? This test was used alot back before it was a common knowledge item to look for with this concern.

Nope.

Jay

I dug this up online.
http://www.well.com/~mosk/Images/22RTE_EFI.pdf

This factory wiring diagram has two things of intrest, that I will use to give further proof to what I claim. ( older vane type air flow meter )

On page 1, youll find the air flow meter. The switch labled FC is the "Fuel Control" switch in refering to. Trace the wire one direction takes you to the computer (on page 2). The computer will provide a ground in this circuit when all parameters are met. Trace the wire the other direction leads you to the circuit opening relay. One of the circuit opening relays coils can be grounded by the FC switch in the airflow meter (indicating that the engine is turning). Also, youll see that the other coil is wired from the ignition switch (ST1). With the key turned to the start position, current can flow thru this other coil to turn on the fuel pump. (which i had forgotten, until i revisited this schematic).

In short, the fuel pump relys on the circuit opening relay to complete its circuit. The circuit opening relay can do so by recieving a ground from the air flow meter, or get a power source from the start terminal in the ignition switch.

Wish I had the real instruction manuals, Toyota teaches it better.

gwhayduke

My '99 takes just a little longer to start up than my '95. And if it doesn't catch the first time (usually because I let off the starter a little too soon), it'll take even longer the second time. It's irritating, but I figured it had something to do with the cold start system and that behavior was programmed in somehow. The '95 always fires up quick, no matter what.

cruzin1a

My 99 limited I've had for about a year and a half also starts slow and sluggish. I can not report one other single problem with the truck. It runs great. I'll re-read the post and maybe I can offer some info.

dragr1

iTrader: (3)

Mine used to have to turn over a few times before starting, but now oddly enough after replacing the clutch it starts right up. Maybe the starter was getting out of line or something?

Roadtripr

hmm. I wonder if the clutch might be my issue too. Seemed like it would start when I pushed the clutch cancellation button, but not always.

What up with the octopus avatar?? (one of the posts on page 1)

Ebbsnflows

Just to echo what many have already said. I have a 2000 4Runner w/ 66K miles on it (I bought it w/ 60K miles)....It has always taken an extraordinarily long time to start as well (regardless of hot or cold temps). On a side note I have a 95' Accord w/ 177K miles on it that fires the very instant that I turn the key (even on 20 deg mornings). I hate to say it, but it's almost embarrassing having to crank my 4Runner for that long in order for it to start. Toyota has a strong reputation for reliability, but this issue really concerns me (especially so early in the life of the motor)

Yotainmyblood

sorry but he is correct. The fuel pump does not come on when the key is in the on position. Only when you are cranking. Then it drops the signal from the ignition and when I turns over it picks up the signal from the MAF sensor. That's why they have a open circut relay. Unfortunately that's how they did design it.

Yotainmyblood

it will not pressurize while in the on position. You have to be cranking it before the fuel pump starts to pump. Then it picks up the signal from the MAF sensor once it fires up and key is in the on position. I know I'm a little late to the ball game, but I just can't stand to see misinformation. Sorry these aren't chevy.

2ToyGuy

When my 87's been sitting a while, a few days, I always turn the key to START, but do not push in the clutch, or the Clutch Start Cancel switch. I can hear the fuel pump "whine" when I do that.. After 10-20 seconds, the pump's tone drops a little, IE, a slightly lower whine. Once it does, I push the clutch in and VROOM! Engine fires right up.

It's also a good way to make sure the fuel pump runs when it should during the start sequence. Part of the testing if your COR or MAF are suspect.

Have fun!
Pat☺

83

What's the buzzing noise at the fuel pump I hear when my key is in the "on" position, then?

2ToyGuy

The newer trucks, and 98 IS newer than 87, the fuel pump runs for a few seconds when you first turn the key to ON, before you go to START, to pressurize the fuel system to make it start faster and easier. Especially as the truck gets older, the anti-backflow valve in the pump can, and will, leak a little, so over a relatively long time not running, the fuel system can leak down.
This set up compensates for that, so the truck will start more quickly and easily.

Does that help?
Pat☺

83

Oh, I don't know. I guess my point was that I'm not sure yotainmyblood is right. If I leave my key in the on position, there is a buzzing, which I always thought was the fuel pump. Constantly. It does not stop. I don't know for sure, that was just my understanding. I'm not sure his information is accurate for the forum he's posting in, being 95.5-2005. But I'm not an expert, could be wrong. My truck has always been this way.

Yotainmyblood

I guarantee you im right. End of story! Now that's not saying that if you do what he is saying about not pushing in the clutch that it won't come on? But the key is in the cranking position and not the on position. Now pre 91 trucks and 4runners I can't speak for but everything from 91 to 05 I know I'm right. I have rebuilt these things front the ground up, several times. The relay works a little different than the 3.0 do. It gets power from the ignition and the crank sensor. . On the 3.4. And on the 3.0 it gets power from the ignition and the MAF. ( of course I'm talking about the open circut relay) which is the reason on all of them that the fuel pump don't run with the key in the on position unless it has started. ( sorry for any confusion) I was just thinking of the earlier 3.0 when I first answered but then noticed it was on a 3.4 and knew that it still has an open circut relay and it works the same off the ignition side.