bwitmer

Hi,
I'm a 4runner newbie, having just bought a '89 4runner with the 6 cylinder engine. It has a gas leak somewhere- it smells pretty strong when you start it and while its running, and i can see some dripping. The previous owner said that her mechanic diagnosed it as the "starting" fuel injector, and that she's driven it this way for several months. To start it, she would just turn the key for 10 seconds w/o hitting the clutch to activate the fuel pump and pressurize it, as it seems to lose its pressure while sitting, and then push in the clutch to start it. This seems to work well, but seems dangerous.

Any thoughts on what the starting injector is- is that a regular fuel injector, or another one?
I've looked for threads on replacing this but haven't found much. Are there any on here, and is this a pretty tough job? I'm not a master mechanic, but I've done a fair amount of backyard tinkering. I've thought about getting the Autozone AllData DIY subscription for this to help me through it, unless someone here is willing to be "hired" to talk me through it!
Thanks!

jason191918

My guess is that it is the cold start injector.

DSCF0743a.jpg?t=1205808542

The cold start injector is a 7th injector only for used for starting. It is located just up and to the left of my arrow (the arrow was for the EGR removal thread). Never messed with the injector, but that is what it is and where it is.

js9924

probably talking about the cold start injector it is in the intake plenum on the opposite side from the throttle body on the 3.0 test it per the service manual.
Basically this thing is connected to a thermostat and when it reads below a certain temp it uses the cold start injector to help start the car by throwing some fuel in before the cylinder. You should also check the temp sensor for the injector I believe it is on the throttle body. I suggest searching for cold start injector.

Thats it in the pic above pop the clip off with a flathead and you should probably replace the crush washers on the banjo bolt

bwitmer

Thanks to both of you for your responses, I was able to find it right away. I'm wondering if that's where the problem is though- when it's running, there's a steady drip of gas that appears to be coming from the rear of the engine somewhere, likely under the intake manifold. It's dripping on the transmission pretty steadily. Any ideas on how to check what it is, w/o removing the intake manifold?
i assume that if unplug the plug on the cold start injector and it stops I can assume thats the problem, and if it keeps dripping then it's something else.

How much of a PITA is removing the intake manifold?
Thanks again,
Brian

thook

Sounds like the fuel pulse dampener is leaking. There's a small screw that fastens in the middle of it that folks have had the same problems with.

Look at this blow out diagram of the fuel injector system. You can see the fuel rail on the passenger and a round component on the end of that that, on your vehicle, will be towards the firewall......ironically , right over the transmission.

SEAIRESCUE

Unless you see fuel dripping from the cold start injector, you have a fuel leak under the intake. You can put a 10mm wrench on the cold start injector nut and attempt to cinch it down with hopes that the drip will stop. Careful, that injector holds pressure with the engine off.

With all the reported 6 cylinder engine fires, I suggest you quit driving it until the leak is found. The injectors attach to two fuel rails with two hard lines between them. All have gaskets of some sort that can leak.

There is a small fuel hose, visible in the front of the motor, at the fuel pressure regulator to steel line that runs under the intake. Check to see if its dripping or the pressure regulator is dripping.

Removing the intake is not bad if you pull the 8 fasteners and flip it towards the passenger side.

My $0.02

bwitmer

Hi Mathew -
you mentioned looking at the blow out diagram to show the fuel pulse dampener- which were you referring to? I didn't see it on the post. Thanks again, that might be it. Do I have to take off the intake manifold to get to it?
Thanks-
Brian

thook

Uh...yeah, man. Sorry. I think I got interrupted by strong lightening storm. Now that I've had a beer, I don't remember exactly what happened. I'm such a cheap date. Now, I just need some girl to take advantage of me. Where's my wife?.....

http://personal.utulsa.edu/~nathan-b...90injector.pdf

RRIND

I had the same problem on mine, little bit of gas on the ground, towards the back right side of the engine and the smell of gas upon start, on mine it was the fuel pulsation damper.

In that pic here http://personal.utulsa.edu/~nathan-b...90injector.pdf it's the thing that looks kinda like a hat at the back end of the RH fuel rail.

They're not cheap and they're not easy to get to either, the stealership wants over a $100.00 bucks for one.

RRIND

904_runner

Mine caught fire from that(what ever its called) the thing on the end of the fuel rail. We ended up putting locktight on it and screwing it back in.

Carry a fire extinguisher.

bwitmer

Hey, thanks for all of your help. I assume that the intake needs to be removed to get to the damper...I'm not looking forward to that. Oh well!

jason191918

Pretty sure if it was the cold start injector, unplugging it would not stop the leak.

jason191918

[QUOTE=SEAIRESCUE;50782263]Careful, that injector holds pressure with the engine off.[QUOTE]

Found that out the hard way...

thook

Here's a thought....

Once you have the upper end pulled off to look at everything, take a paper clip and put either end between the two terminals FP and B+ in the grey diagnostic port on your pass. side fender well......next to the fuse panel. (I assume you have that style). That will manually run the fuel pump and hopefully show you exactly where your leak is coming from. Don't run it too long...just long enough.