SOLVED! Post 2853 Leaking Injectors, Dealer Techs Rock! Extended Cranking after Engine Swap 3.4L 5vz

http://www.knowyourparts.com/technical-articles/replace-a-fuel-injector/

looks like a good article, reading this in the AM : )

After watching injector videos more, it looks like (at least on #2) that it is trying to pulse when it shouldn't be???? Does it look like that to you guys? Weird.

 

After reading that, sounds like we need to change that 02 sensor. I wonder if it is heat soaking and screwing up everything. I remember it was checked, and it checked out fine. Was it checked while hot?

 

Whoa, just read and saw what you are talking about. Even after a whiskey, I see what you mean K. New O2s would be a heck of a lot cheaper than all new injectors......

And would explain a lot, because we've heard the guy that did the injectors in Jan are super good....let's hope malfunctioning O2s are confusing injectors!

Glad you are having a good time down there, and glad the donor parts for drinks swap worked out buddy Enjoy!

 

Sung to the Beverly Hillbillies theme : )


Wanted to quote this fabulous song writing talent, to be sure everyone got to see it. Good stuff, thanks Steve!

 

Just found my notes about our O2 test results, from back in February, done at home per FSM (with neighbor's nice tool, not the craptastic HF one!).

Results were within spec per FSM (spec range is 11-16 for both).

Upstream was 12.6
Downstream was 13.3.

We debated about getting the truck hot to retest them, BUT the FSM does specify that they should be tested at 68 degrees, and ambient was 54 when we did the test.

I remember thinking, hmmm, the upstream is pretty close to the end of the spec range....

And no yelling at me TW people (DP!), but I can't remember the specifics on how EXACTLY how the O2s work. I know upstream reports to ECM, which in turn alters A/F ratio. And downstream just monitors the cat, right? But I swear I remember learning that the O2s don't report during open loop, which is always the mode the Taco's in when it's cranking, right? Then once it's warm and goes to closed loop, then the O2s report, right? So then how could it be that a bad upstream O2 is the culprit?

And I remember learning that newer trucks have 4 O2s, to better pinpoint which cylinder is lean/rich/misfiring, whereas an older truck like the Taco only has 2, then the upstream just takes the consensus of all 6 cylinders as far as what the A/F ratio is and whether to adjust it. Right? DP, am I earning a gold star today?

Gonna go back and read some on that now I think.....but everyone feel free to re-educate me on this if you are up for it!! : )

PS - @koditten, did you ever do anything with your 98's injectors? Same set all 300K? Ever have them serviced?

If I remember right, DP's had his same set for 240K and counting, but has a pretty impressive maintenance protocol he does. Just strange that our injectors have had so many prob's......really wondering if they were damaged by using a bad chemical on them during engine swap or something......

http://www.samarins.com/glossary/oxygen_sensor.html

Decent article, dumbs down the explanation of how O2s work in general. Assuming this info would apply to the Taco......it says:

"When the car is started cold, the front oxygen sensor is not fully warmed up, and the PCM does not use the front O2 sensor signal for fuel trim adjustment. This mode is called an open loop. Only when the oxygen sensor is fully warmed up, the fuel injection system goes into the closed loop mode."

Thank you College of Google!

 

Well shit.

 

Original injectors with zero maintenance...in actuality, I abused the shit out that fuel system. I would routinely burn leftover boat fuel that was mixed with 2 stroke oil.

 

I'm sitting a bar on Marathon Key watching a major, rare, all day down pour. This post made me laugh.

 

Headed your way,,save me a spot.

 

Me too!

 

Frank and Taco have a very important conversation......

 

Took a side trip to Robbies. They have Tarpon that hang out at the docks. I was so close to grabbing this one when I was feeding them...one of these I'm gonna grab one.

 

The 90K Toyota change interval seems to be very conservative. I have changed out a bunch of them all between 90K-120K or so. They all looked to have lots of life left. That being said, things like condition of the pulleys an leaky water pumps factor into it. It's pretty easy to pull the black plastic upper t-belt cover and have a look. I have never seen the cam seals leak so I don't use the "kits".

 

Jen, I think your confusing me with someone else. I just "try" to use top tier gas, toss in a can of cleaner now and then if I remember and have burnt my share of old boat gas (ex powerboat tech).

 

Performed fuel injector leakage re-test this morning. Confirmed all the injectors were dry before doing anything else. Then ran the pump with the scan tool to pressurize the fuel rail and noted the following: Cylinder 1 and 2 are the worst leakers showing large drips (pics)





Cylinders 3, 4, and 5 injectors appeared wet. Cylinder 6 appears dry

All testing was done with injectors unplugged b/c some peoples were thinking there could be some problem with slight current flow or voltage issue



Conclusion:
So given that we can see the injectors are leaking fuel when the truck is turned off I seriously suspect that this is the extended crank / hard start issue after a hot soak. My recommendations are to replace the injectors with all new Toyota oem injectors. This actually might be kind of expensive so it could wait until further down the road you would just have to expect the hot soak issue is going to happen. The truck does always start after the extended crank. I have never had the truck crank and not start.

 

Well folks, I think we have found the end to the mystery on this vehicle.

 

Holy cow. Am I dreaming right now? Did someone FINALLY find the hot start culprit? Unblankingbelievable. You are a genius noahpete!!!!!!!!

Just called Eric the second I saw your post. He's gonna call me back soon and we're going to talk about what we want to do. I suspect we will have some questions coming your way, in hopes of getting your overall recommendations on a few things before making the big bucks ($1200) decision on the injectors. I know our concerns about the health of the engine are definitely on the lists of things we're hoping to chat with you about.

But for now, thank you thank you thank you, you are an absolute angel for working so hard to figure this out for us!!!!!!

PS: cookie preferences? : )

 

Jayman, special thanks to you for hooking us up with the most brilliant, hard working, dedicated, kind hearted mechanic we've ever had the pleasure of meeting. You were not exaggerating when you said this guy is diligent and determined. Wow. We are beyond impressed, we have never had such an above and beyond awesome experience with ANY mechanic, ever. The incredible amount of additional, above and beyond effort noahpete put into this, with all of the informative posts every single day, after putting in full days working on it and I'm sure many other vehicles, wow. Just stunned - that is some work ethic!! Give that guy a serious promotion and raise!!!!!!!! CHEERS you guys, thank you so much!!!!

PS - cookie preferences? : )

 

Edit: You are welcome!

I am a peanut butter guy. =)

Jay has done a great job. He has impressed me again.

 

We still have the plenum removed, and waiting for your decision. I see we have 3 injectors instock, but could have the others tomorrow if we get them ordered before 3:50pm.

No pressure, no rush.