'01 Tacoma fuel supply issue?

[srogers]

Morning all - original owner on an '01 Tacoma 4wd, 3.4L, 101k miles, manual tranny

Within the past several months the pickup has developed an annoying habit of, after the rig has been driven briefly and warmed up and I then stop for a few minutes (i.e. 5 minutes or so - getting gas, running into a store, etc.), it will refuse to stay running.

The rig will turn right over, hit 800 to 1k RPM as normal, and then immediately die. Cranking it again it will act as if it is starving for fuel - it'll have to crank several times before it finally turns over.

I can prevent it from happening if, when attempting to start it right after getting gas, etc., I just rev it up to about 1500 or 2k RPM and hold it for 15 or 20 seconds.

No recent maintenance - I replaced the fuel filter last fall, but other than that nothing. I'm current on all maintenance, done at a dealership at 90k miles, but no other changes since.

Thoughts?

 

[Duane]

challenging question..hmmm
Thinking back if it were carbureted I would be thinking choke,vacuum and high idle setting...
so as it is now an ECM with a MAF, O2 sensor, TPS, rpm sensor, temp sensor, fuel pump and injectors, multi coil ignition and so on then the scenario/symptom should be the same... not sure where one starts here though.

- Fuel one would think is ok if you can rev it up and keep it there.
- thus something wrong with it's ability to maintain the proper air/fuel mix and maintain an rpm
- I would do a visual and listen to see if any vacuum lines have cracked. I recall looking at an 03 with a cracked line near the back of the intake.
- I'll have to sleep on this one some more..any engine codes thrown?

 

[srogers]

Good suggestion re: vacuum line, I'll take a peek and look around the back of the intake and see if anything jumps out at me. No engine codes thrown, and no other issues (i.e. doesn't run rough, no change in mileage, etc.), and it doesn't happen every time - altho it is getting worse. It would happen every once in a while, and now it's about every third or fourth time...

 

[hoch]

Maybe some bad gas? Had a CEL come on in my old car from bad gas. Although it never caused the engine to die.

Curious to see what you find...

 

[raydouble]

Did the CEL ever come on?

I have heard of this happening a few times with a dirty MAF sensor.

 

[srogers]

Started the rig and poked around today, no visible issues with any vacuum hoses but I'll focus on the MAF sensor and see if that can be the cause...

No check engine light has ever come on

Hey Cackalak - I don't think it is bad gas - this rig is my daily driver, so I go through about a tank a week and cycle gas pretty quickly. My rigs that sit I usually dump marine Stabil in the tank or I get "off road only ethanol free gas" just for that reason...

 

[srogers]

Quick follow up - did a search on MUD for MAF and Tacoma, and a reference to K&N filters fouling MAF's came up...I've got a K&N in the rig. Pulled it out and when back to paper, and will pull the MAF and give it a once over when it isn't 20 degrees with snow coming in sideways!

Would it be wiser to try and clean this (i.e. with carb cleaner?) or just pony up and replace with an OEM? Don't want to try a "shotgun" approach to troubleshooting but...

 

[hoch]

From everything I've read, use denatured alcohol and be very very careful. And definitely avoid K&N air filters.

 

[raydouble]

I use this


Works great, dries fast.

It is probably just really dirty from the K&N oil. Check it....
Toyota 4Runner Highlander Mass Air Flow Sensor MAF cleaning

 

[Duane]

I use this
http://imageshack.us

Works great, dries fast.

It is probably just really dirty from the K&N oil. Check it....
Toyota 4Runner Highlander Mass Air Flow Sensor MAF cleaning

How often do you clean yours? Any idea on the cost of a new OEM sensor?

 

[raydouble]

How often do you clean yours? Any idea on the cost of a new OEM sensor?

I clean mine every 15,000 to 30,000 miles......not much "dirt" in there. I just going to start doing it every time I change spark plugs. (30,000)

I just checked the cost from 1sttoyotaparts.com.

Pre 98 is damn near $600 at the discount.

Post 98 is right around $120.

Big difference.

 

[srogers]

I picked up a can of CRC's Mass Air Flow cleaner for $5, I'm going to follow the write up in the referenced link Friday (merry Christmas to me - a rig that'll start every time!) and see if that resolves it...given that I've NEVER cleaned it (I'll admit it) I am hoping that it will take care of it. While I have the air box assembly out I'll probably give it a thorough cleaning too, just to remove any oil or other residue from the K&N while I'm at it.

 

[raydouble]

I picked up a can of CRC's Mass Air Flow cleaner for $5, I'm going to follow the write up in the referenced link Friday (merry Christmas to me - a rig that'll start every time!) and see if that resolves it...given that I've NEVER cleaned it (I'll admit it) I am hoping that it will take care of it. While I have the air box assembly out I'll probably give it a thorough cleaning too, just to remove any oil or other residue from the K&N while I'm at it.

Good plan, I think you will happy with the results.

Post up after you clean it and hopefully she's purring again.

 

[srogers]

Followed the instructions in that 4-runner write up, man that MAF was nasty...

Got it cleaned up with the MAF cleaner (in stock, $5.98 at my local Baxter's), simple green'd the air box and scrubbed it down, reset the EFI, and ran like a champ on the way in this morning...I'll see if that resolves the odd starting issues I've been experiencing as of late

 

[raydouble]

I'll see if that resolves the odd starting issues I've been experiencing as of late

I bet it will, that is nasty.

 

[Duane]

Got it cleaned up with the MAF cleaner (in stock, $5.98 at my local Baxter's), simple green'd the air box and scrubbed it down, reset the EFI, and ran like a champ on the way in this morning...I'll see if that resolves the odd starting issues I've been experiencing as of late[/QUOTE]

How is it running since the MAF cleaning?

 

[srogers]

Been running good, it did it once since I cleaned it but that's been it so far - no noticeable difference in mileage or any other changes (i.e. power has remained the same, etc.) - if it does it again I'll go back to the drawing board and see what else it might be...

 

[raydouble]

You might try to pull the intake tube off the throttle body and see if the butterfly valve is covered in the same oil residue.

 

[srogers]

Hey, quick follow up to this - work has been hectic (single digit temps for a week caused a rupture in one of the 1.5" sprinkler lines in the ceiling and having to deal with the restoration), but finally getting around to this.

Got access to the butterfly valve on the throttle body - man, that thing was nasty! Hammered it for about 10 minutes, spraying carb cleaner, hit with a cheap tooth brush, repeat, until it cleaned up. Brown crap would just flow out of the TB when I sprayed carb cleaner, finally got it tidied up in there.

Fired right up tho, ran a bit rough as it chewed through the carb cleaner, but smoothed out, let her get up to operating temp and then took for a spin.

So far, so good - I'll keep an eye on it and see if that has resolved this...

 

[raydouble]

Hey, quick follow up to this - work has been hectic (single digit temps for a week caused a rupture in one of the 1.5" sprinkler lines in the ceiling and having to deal with the restoration), but finally getting around to this.

Got access to the butterfly valve on the throttle body - man, that thing was nasty! Hammered it for about 10 minutes, spraying carb cleaner, hit with a cheap tooth brush, repeat, until it cleaned up. Brown crap would just flow out of the TB when I sprayed carb cleaner, finally got it tidied up in there.

Fired right up tho, ran a bit rough as it chewed through the carb cleaner, but smoothed out, let her get up to operating temp and then took for a spin.


So far, so good - I'll keep an eye on it and see if that has resolved this...

Hopefully that will be the end of your issues, that K&N oil didn't do you any favors.