Rough Start Up - Engine Sputtering Video

Yeah, priming the pump would help, unless the source of the leak is an injector that's leaking into the cylinder/manifold and then priming won't help at all because the problem is an overly rich/flooded condition. The way it's chugging on that start, I'm starting to think that might be it. The last vehicle I had that sounded like that the o-ring on an injector in a side feed rail I had just rebuilt got pinched, and it was dumping fuel into the cylinder. Sounded JUST like that chucking into a really slow, hesitant start.

And if that's it, you need to change your oil immediately too because you're dumping fuel into the cylinder which is washing down the cylinder walls into your oil and diluting it, reducing lubrication and protection.

 

Dealership 2 was able to recreate and record a fuel pressure leak. They are opening a case with corporate for additional support. They are leaning towards one of the fuel pumps. @Yzkiley

 

"one of the fuel pumps"... how many do we have..?? I thought we had only one..!
Good luck... hope it gets fixed for ya..

 

Think there may be a small one in the tank.

 

We have two fueling systems but even in direct injection only the hpfp is a mechanical pump. There's still an electric pump in the fuel tank.

 

I wonder how one could determine whether there is a fuel pressure leak based on OBD data? given the chirping sounds and how high pressure that one pump runs I have always had concerns around fuel delivery in these trucks but don't really know what to look for / how to correlate.

 

you can't, they'd have put a pressure tester on the fuel rail. About the only way you'd have a potential marker for a constant pressure problem would be seeing huge positive LTFT values and/or learned knock correction.

Fuel pressure can be extremely difficult to troubleshoot. I had a forged EJ25 Forester that I chased my tail on for some time with surging in power delivery after having installed ID 1000cc injectors and fuel rail. Turned out, the injectors were so large, that pulse width had to be so narrow in low load conditions that the pulses were wreaking havoc on fuel pressure which caused giant pulses of pressure that would create harmonic waves and cause momentary lean spikes in specific cylinders that, under just the right rpm/load, would end up creating surging power (not unlike what we have felt on our trucks). I datalogged the shit out of that tune and tried changing a LOT of things that never put a dent in the behavior.

I found it by throwing on a pressure gauge that I rigged to a long hose that I could then mount in the cabin and go for a drive. The needle would bounce back and forth so fast it was blurred into a +-15 psi wave at that RPM range.

Here's some videos I took of what it looks like at idle before I fixed it. Adding fuel line dampers to the beginning and end of the fuel rails resolved it entirely. Listen to the difference in sound!

 

^^This^^ I would also check and clean the battery terminals if needed and do a deep trickle charge on my battery, the longer the charge (like over night or the weekend) and lower the amp setting the better

Cheers!

Edit: I do the trickle charge once a month on all my vehicles

 

Are gdi engines more susceptible to changes in rvp or the 'wrong' rvp?
I've read it can vary from 7-10 psi...
Does E10 have different vaporization characteristics than E0?

 

That's above my pay grade. I can speak to fuel line pressures but when talking about RVP, you're getting into fuel properties that I know nothing about.

 

I know this doesn't help but my 2nd gen would do that about once every couple weeks since new. Never got it figured out before I traded it in at 80k miles.

 

Update: Dealership said Toyota wants them to run some additional test. The Service Rep said he wasn't sure on the specifics but involves isolating fuel lines for testing... Still no fix proposed and another day in a Corolla.

 

Dang when I know I'm going to be sitting somewhere for a while I bring something constructive to do with my time.

 

Holy shinola a 2nd gen actually having a problem like a 3rd gen ?
Say it ain't so.
Smitty you fainted yet ?
Where are the 2nd gen white knights to the defense ?

 

Update : Toyota decided to replace the pump in the tank. Part should be in tomorrow and installed by the afternoon.

 

OBDII is open so a manufacturer can add their own data codes and also relay analog data to a computer. The dealer might have graphed out the pressure data and saw the pressure was lower than spec.

 

Hopefully that solves the issue for good.

 

They received the pump and started installation. During they had issues pulling off a hose and ended up gnarling it up so much they have to replace it. Have to wait one more day now for the new hose to come in to finish the install.

 

So all is finished up with the pump in the tank repair. Replacing the pump had no affect on the sputtering issue. Next step is to wait until Monday to update Toyota Corp and see what they want to do next. 1 day for them to decide, 1 day to get the part, and 1 day to fix so best case scenario I'll have my truck Wed evening.

 

So far to date I've changed
fuel pump
fuel pressure regulator
All injectors
cam position sensor
Crank position sensor
fuel pump relay
Long start remains