98 4runner 3.4L requires throttle to start

[Scag]

I have a 98 4runner with 240k and lately I've noticed that I need to give it a little throttle in order to start. On the first try it will turn over fine but immediately die. If I try again and give it throttle it will start rough but get me going fine. It will idle fine and accelerate fine. I drive 3-4k miles a month with no problem - only in the last week have I started to notice the issue. Coincidently, it has recently started to cool off here in fl and am wondering if it could be contributing.

Several years ago I had an issue starting and cleaning the maf fixed it, but in that situation, the vehicle wasn't really turning over.

Where should I start? Fuel pump and filter are less than 6 months old, but are aftermarket stock spec.

Thanks in advance!!!

 

[Swimmerboy2112]

I have a 98 4runner with 240k and lately I've noticed that I need to give it a little throttle in order to start. On the first try it will turn over fine but immediately die. If I try again and give it throttle it will start rough but get me going fine. It will idle fine and accelerate fine. I drive 3-4k miles a month with no problem - only in the last week have I started to notice the issue. Coincidently, it has recently started to cool off here in fl and am wondering if it could be contributing.

Several years ago I had an issue starting and cleaning the maf fixed it, but in that situation, the vehicle wasn't really turning over.

Where should I start? Fuel pump and filter are less than 6 months old, but are aftermarket stock spec.

Thanks in advance!!!

My Tacoma did this, turned out to be a vacuum leak! Hope you find the problem.

 

[Snowy21]

IAC is my first inclination... Does it idle fine when hot?

 

[vipergrhd]

Leaky injectors perhaps?if the plugs are flodded there is a good chance you need to open up the throttle to give it more oxygen to fire up.

 

[Scag]

IAC is my first inclination... Does it idle fine when hot?

Yes - idle is perfect.

 

[19963.4lsr5]

How old are your plugs?

You could try a double dose of dry gas.

 

[Scag]

How old are your plugs?

You could try a double dose of dry gas.

Plugs were replaced around 160k i believe - and it has 240 now...probably about 4 years old.

I have some star tron....is that a substitute for dry gas?

 

[Snowy21]

Yes - idle is perfect.

I'd start with the IAC and work from there. The IAC is just a controlled vaccum leak that raises the cold idle of the engine so if it were gummed up, it would show it's head especially as it got colder

 

[Scag]

I'd start with the IAC and work from there. The IAC is just a controlled vaccum leak that raises the cold idle of the engine so if it were gummed up, it would show it's head especially as it got colder

I'm going to try to tackle that this evening. Thanks!

 

[TheDurk]

Try to diagnose rather than just change parts. Hook up a scanner--for $35 with an Android phone you can get a bluetooth adapter and the Torque app. Is the truck starting in open loop as it should? What temp is the ECT showing on a cold engine? What throttle percent does it show before you turn the key? Any stored codes? Watch what happens to all the parameters as it warms up and switches to closed loop.

Or if you just want guesses mine is ECT sensor.

 

[Robb235]

My bet is Idle Air Control Valve.

 

[ChildrenOfBodom]

If the IAC isn't it, I'd consider checking the TPS too. I had this issue wth early TPS failure.

 

[Snowy21]

If the IAC isn't it, I'd consider checking the TPS too. I had this issue wth early TPS failure.

And then bend over if you have to order a TPS....it has the equivalent value of unicorn poop according to Toyota