The hard starting bug when cold bit me last year right before the holidays. It turned out to be the fuel pump. There is a check valve which holds pressure in the pump once the key is shut off. Over time this valve loses its ability to keep enough pressure (primed) once the car is shut off to provide instantaneous cold start up.

My brother's mechanic friend told me that the ethanol is not kind to the components to the valve; more than likely though time ultimately killed it.

 

Thanks for responding to the bump.

J2F42C: Did the fuel pump problem change with the outside temp? My problem happens the same through the Tucson summer and winter. Wonder if that's a clue for fuel pump vs. crank sensor....

LifeonaBoard: I'll continue to look at the crank sensor threads before sending it back to the Toy shop. I trust them, but $200+ for a diagnostic? Really?

 

Just to re-cap a couple of points:

1. The 4runner doesn't prime (pressurize) the fuel rail until the engine starts cranking. In light of that, a faulty check valve shouldn't matter. But a pump that is slow to build pressure would matter.

2. I believe most of us here have a delayed spark. This can be determined with a simple "timing light". Connect it as usual (wrap the sensor around plug wire #1) and have someone point the gun at you while you crank the engine over. You'll notice that the probe starts blinking when the engine finally catches. If the probe turns on before the engine starts then you have spark but you don't have enough fuel or fuel pressure.

3. I was able to override the fuel pump relay which allowed me to turn the pump on before cranking. Even with the fuel rail fully primed starting performance did not change. Either the injectors aren't opening or the plugs aren't sparking. Probably both. The lack of signal OUT is most likely a result of no (or low) signal IN. The IN signal is the crank and cam sensors. The ECU isn't going to fuel an engine that isn't spinning.

4. I did replace the Crank Position Sensor and signal strength did not change. The only thing I can do to get a stronger signal is to position the magnet closer to the teeth. BUT, this is just my latest theory, it may be wrong.



bnk87: If you pay them to check the fuel pressure please have them check the effectiveness of the fuel pressure REGULATOR. I've found that mine doesn't reduce pressure so it just stays constant 3 bar.

 

Maybe the mechanic was feeding me some garbage then. I do not know, but the fuel pump replacement did the trick. The 4runner runner was harder to crack as the amount of gas in my tank dropped. Below a 1/4 of a tank and it could be 3+ seconds before fire. Outside temp had little to no impact.

If you have delayed spark, then have ya visited a yard to pull a used igniter or know of anyone with another 4runner? My friend had one go south on him in his T100 but it produced a code, I think P300 and another one if I remember correctly (it has been 3+ years).

Good luck to both of you.

 

Did you ever get this figured out? I'm having the same problem. I was thinking maybe an injector is stuck open allowing the fuel to drain out of the rail and onto the piston. I'm going to pull the plugs and see if any cylinder has wet fuel on the piston.

 

This problem on my '99 Tacoma still persists. I took it to two more shops. The first saw a slow fuel pressure drop. I let them change the fuel pump but it didn't solve anything. They then said it must be a leaky injector. This would explain 2 things -- a strong gasoline smell during the extended crank and an engine light indicating a failing cat (at only 120k). Also, the engine starts right up if I leave it for a week -- I'm guessing that's enough time for the leak to fully depressurize the rail and then let the gas in the cylinder leak down past the o-rings.

The second shop (I didn't tell them about the fuel injector theory, since I wanted an unbiased opinion) said that I had a stuck or burned exhaust valve, since they could hear the compression stroke out my tailpipe during a compression test. Don't know how this plays into the hard start, but a fuel-rich cylinder could mess up the valves, I guess.

I haven't had the time or $$ to replace/service the injectors or pull the head, but smog test season is coming. I'll post here if I get to that point.

 

Ok I didn't pull the plugs like a was gonna. After driving for about 20 minutes I took a pair of needle nose vise grips and pinched the fuel line at the regulator. Let it sit then removed the pliers and started it. I did this three times, once for an hour, two hours, and overnight. All three times it fired up immediately. So that removes my theory of the stuck open injector. Now I just have to figure out where it bleeding off at. Somewhere between the regulator and the pump. Any ideas? The motor is a fresh complete rebuild with about 750 miles and a new head. And 4 new toyota injectors.

 

Bstaco: Since you were able to stop the problem, you're on to something. I've gotta try this. Here's my amateur thoughts, for what they're worth.

If you can't smell fuel 20 minutes after stopping the car, it's staying in the car -- either bleeding back into the fuel tank through the pump or into a cylinder.

The question is, where is the expandable part of the fuel line that stores the excess fuel under pressure that eventually bleeds out? Gasoline doesn't compress under pressure, so you need a part to give, like a soft tubing or the moving parts within a part. Can't be in the metal lines. I suspect the regulator or pump. So pinching off after the regulator would still pinch off the source of the fuel bleeding into the cylinder. I wouldn't rule out injectors yet. Or am I missing something?

 

Figured I'd bump this thread and see if anyone has come up with a solution.

Mine's a 99 limited with the same issue and it's getting worse. I live in Riverside and it doesn't get "cold" here, so when I refer to cold I mean the engine temp.

First thing in the morning with the engine cold, it cranks at normal speed, but takes a long time for the engine to fire, once it fires I have to keep the key in the cranking position otherwise it will start and die. After 1-2 start / die routines it will finally start and idle normal. The rest of the day there won't be a problem and then the next morning have to start the process over.

My concern is it's taking more cranking before it fires off and it's getting worse. My gut tells me its the fuel pump, but looks like that's been replaced on this thread and didn't fix it. I'd hate to drop the tank and throw money at it only to find out that it's not the problem.

I'll check all the grounds tonight. I do not smell gas after it sits. However, it does smell very rich when it first starts and I figured that was un-burnt fuel while cranking for a long time; another reason it may not be the fuel pump.

 

My 1988 Toyota Pickup is doing the same thing. But only in the early morning. Replaced both the cold start injector valve and the "timer" injector or whatever it's called at the front of the engine. And it starts but only after a while after pumping the accelerator several times.
IMO I think it may be a vacuum line or the egr modulator. But I can't find it yet.

 

. I replaced the head on my 2000 Toyota Tacoma 4WD 3RZE engine
And it started the hard cold start crap on me, after replacing the fuel pressure regulator and fuel pump I figured out it was not a fuel issue. So I'm crawling around the back of the motor and I see a plug hanging from the harness directly behind the head, I plug it in to the sensor on the back of the head which I think is the cam shaft sensor and BOOOOOM. NO MORE HARD STARTS.

 

This morning I left the switch to the "ON" position and left it there for about 30 seconds. It almost started right away I only pumped it once more and it started. Maybe the cold start injection timer needs a little bit of time to heat up and inject the primer fuel as it is supposed to do. Hope if I do this again tomorrow it will start up. It kept on starting all day after it started up in the morning.

 

Got mine fixed, two injector o-rings were cracked and leaking.

Had the issue again, popped the hood and it reeked of raw gas. Guess the low temps amplified the cracked o-ring issue. Replaced the o-rings, spark plugs, and wires = no more gas smell and no more problems cold starting.

 

Going to bump this moldy oldie.

1999 4R Limited 245K - salvage engine installed about 70K ago. So this is a 5VZ-FE.
Truck runs great. Zero misfires. Zero power issues. Mileage what is expected.
Had a faulty injector replaced a while back when it started misfiring. Ran fine after. This developed later.
I also had the charcoal filter replaced to clear a CEL. This stopped the weird smells I was getting and is not when this issue started. No fuel smells now.

Problem is hard starting. It cranks and cranks. Stop it, try again, and it generally starts.
It does not sputter start or anything. It just starts right up when it eventually fires and seems completely normal.
This generally happens when it has been sitting but not always. It sometimes cranks longer than it should after just stopping the motor for a short while.
It's nerve-wracking enough that my wife refuses to drive it any longer.
I will try the timing light trick as a quick way to test that spark is not being delayed. Seems like fuel and spark are both possible causes.
This is not in a cold weather climate. Lows below about 25F are rare and that does not seem to cause the symptoms to be any worse.

 

I am scouring through all these forums trying to figure out my possible Fuel Issue. I have an 88 pickup with 22RE. It becomes hard to start after not starting for a week or so. Now its 10 degrees outside and wont start. I jumped the battery and left it over night on a battery charger. Still wont start. I checked for spark, all good. I removed the air intake on the rail and squirted some starter fluid in there. Truck fired right up and quit after burning the starter fluid. I would love to test all the sensors (ECT, MAF, CPS sensor, FPR) all sensors that could possibly be affecting the fuel issue, cause it definitely seems to be a fuel issue.I have no idea where any of these sensors are or how to identify them.I have no manual and cant find what I need on the interwebs. With the key turned on I hear no fuel pump sound. (3 secs). Pump might be bad. Not sure how to test with my multimeter the actual pump. I chaecked all the fuses. Look good. Any reply with where and how to find/test these sensors would be much appreciated!!

 

http://parts.lakelandtoyota.com/p/gb...ITION-FOR-EFI/ You can find most sensors and their locations.

 

Thanks Hawk_man24. I followed the link and was able to find the location of the COR behind the passenger speaker. Cheers!

 

...still own my 1994 4X4 pickup (purchased new). Truck basically sits in the garage all summer because I have a car that gets better gas mileage and a motorcycle for the nice days. Anyways, I've had cold starting problems forever, scary considering I live in Minnesota and on extreme cold days I'm worried that my truck won't start. Found out from this site that the fuel pump only works when the key is in START mode (so turning the key on for 30 seconds before attempting to start is futile). Seemed like I had all the symptoms of a bad Fuel Pressure Regulator (slow starts but once the engine gets fuel the truck runs like a top, however had a lack of power, especially when accelerating or going up hill, horrible!). Ordered a new FPR from Rock Auto $60, installed it yesterday and my truck starts and runs GREAT, I mean really great! Today I brought the old FPR into work here where I cut it open and found there's an internal rubber baffle/gasket between chambers that was totally toast! Best $60 I've ever spent (also you'll need a 17mm crows foot socket to replace, had it changed in 15 minutes). Also checked various rubber vacuum lines, replace a couple that I felt came off a bit too easily. Just thought I'd share my good fortune.