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

Is that canister supposed to make any noise?

 

yep, dats it batman

 

https://www.youtube.com/watch?v=9YDutPdmfP0

OK, seriously guys, this isn't our truck, but after researching charcoal canister clicking today, found this person w/5vzfe swapped into their 4 runner, and it's the exact same sound I'm hearing. Thoughts?

 

https://www.youtube.com/watch?feature=player_embedded&v=nIZ4EGknw2Q

 

You need to take the cover off of the thing next to the thing you took a picture of. You are showing the charcoal canister.

 

Just called mechanic. He thinks we should replace IAC valve. Said the canister will make noise sometimes. Said they checked our entire fuel system head to toe a million different ways, and he really doesn't think it's the fuel pump. They did not clean the throttle body - he said ours just had mild residue, was not coated in gunk like a lot of them he sees. Said we can replace IAC valve easily at home, and OEM is Denso for ~$200 - yikes! Said maybe it got stuck again since he cleaned it. Ugh. They'd charge us $43 in labor he said if we had them do it........hate to throw more $ at this, but nervous to goof something up in there too. What do you guys think?

 

Just looked on Rock Auto - they don't have the damn Denso IAC valve. Amazon has it for $10 more than the $194 mechanic quoted. So sick of trying to figure this crap out guys!

Part of me thinks, we didn't have this issue before engine swap, so how is this our responsibility to pay for/deal with? But then the other part of me thinks, they said they found it stuck (open rather than closed I think), so that's not their problem to deal with. Don't know. Is it possible the thing was screwed up before and we just didn't see signs of it? I'm absolutely certain we never had strange idling issues before, or difficulties starting Taco, or even differences in how she started from one scenario (cold) to another (warm).

Do you guys think this is the problem? Is there some easy way to verify it before dropping the cash and pulling things apart? Koditten, will Scan Gauge tell us somehow?

 

I have a PLX wideband. All wideband units are very similar. First I rented a fuel pressure gauge kit from Autozone but like DirtyPool said, I had difficulty hooking it up to the fuel rail. It required a strange adapter and the timing belt cover was in the way. So next I decided to get an inline fuel gauge off Amazon for like 30$ and installed it in the soft part of the fuel line which can be seen under the hood on the drivers side near the valve cover. I didn't mind cutting this hose as I would be adding a "T" there anyways to install my 7th injector.

I doubt if he cleaned it and verified it worked that it would already be stuck again. And unless he checked the fuel pressure while it was stumbling, he technically didn't check the entire fuel system "a million different ways". If you check the fuel system while its running normally, you're obviously gonna get good numbers...

Changing my fuel pump was actually not as bad as I thought. I chose to remove the bed rather than drop the tank. All I had to do was remove the 6 bolts holding the bed down, unplug the tail lights and pull out their harnesses front the bed, and undo the 4 screws and 1 bolt that holds the filler neck in place. Then I grabbed one side and my cousin grabbed the other and the bed lifted right off. The fuel pump is then right there and you can easily remove it. I didn't have a single corroded bolt that broke or anything.

 

Thanks for the reply kigmob. Wow, you made that sound almost easy! Still, not sure if we'd be up for it....I'll show husband your post and see what he thinks.......

I specifically asked if they checked fuel pressure during a rough idle (like you guys suggested) and he said "yep" then said "we had the gauge on it for a couple days and started it under a variety of scenarios" - I don't want to doubt what they tell me, but yeah, still not feeling 100% about ruling out fuel pump, after seeing SO MANY others have that be their culprit.

 

Kigmob, thanks also for your thoughts on the IAC valve.

Anyone else have any thoughts on this?

Is it possible the thing (IAC valve) was screwed up before engine swap and we just didn't see signs of it? I'm absolutely certain we never had strange idling issues before, or difficulties starting Taco, or even differences in how she started from one scenario (cold) to another (warm).

Do you guys think this (IAC valve) is the problem?

Is there some easy way to verify it before dropping the cash and pulling things apart?

Koditten, will

$160 ScanGauge - SG2 II Ultra Compact 3-in-1 Automotive Computer with Customizable Real-Time Fuel Economy Digital Gauges , Black , 5"

Scan Gauge tell us somehow?

 

Fuel pump change out sounds more involved than it really is, discounting rusted fasteners. On this planet and from someone that has actually done this job on a Tacoma, the bed is secured to the frame with 6 bolts. The wire harness to the tail/license plate lights needs a little attention also and the gas cap should be off. The bed does not have to come off. Remove the 3 bolts on the driver side and loosen the 3 on the pass side then tilt the driver side up and secure with blocks. You will need a bit over a foot between the top of the tank and the bed to extract the pump and fuel level float assembly. You will be working in cramped conditions and cleanliness is next to godliness here.

Dropping the tank itself. The tank is secured to the frame by the 3 screws holding the front of the fuel tank skid plate and 1 strap in the rear. The strap comes off with a couple spring Jesus clips (Jesus, where did they go!!) . Then there are 2 clamps for the fuel filler pipe and the e-brake cable. When empty (as it should be) the tank is surprisingly light but still should be "lowered" in a controlled manner with a floor jack paying attention to what's going on with the filler pipe (gas cap removed).
In the end the easiest method will be determined by the condition (rust) of the fasteners involved. It took me (having done it on other Tacos) less than a half an hour to get my tank on my work bench where I could work on it and clean things up like a gentleman.
How ever you go about it, get the Denso "fuel pump and strainer kit" from RockAuto for a few $ more than the pump alone. A year ago it was over $100. Not a bad idea to get the gasket also.

The charcoal canister (fuel tank evap control) is usually pretty benign as far as engine operation goes, they do contain check valves that click and clack now and then. The earlier units more so than the later. A little box was added to minimize the clicking (red arrow). It does however pose the potential to allow a vacuum leak right into the throttle body causing running problems. If you want to "take it out of the picture" temporarily to see if it changes anything, disconnect and plug the engine side of the hose below (blue arrow). This might set a check engine light that can be reset afterwards.

 

Wow, thank you so much for the detailed explanation DP! Definitely makes it a little less scary. Really appreciate all your help.

Just not sure whether to throw time/money at this first, or the IAC valve first. Or who knows, maybe it's neither of those!!!!!!!!!! Good times. Good grief. I need more wine.

What happens if it is the IAC valve, and we don't replace it? Will something bad eventually happen, or will it just start funny/idle funny, and those things will eventually get worse? All I really care about at this point is not letting our giant investment (the engine) be damaged by overlooking some seemingly harmless thing.

 

If they didn't clean the t-body of the IAC I would try that before replacing it. Folks routinely clean v6 Taco IAC's with good results. It will only cost 2 gaskets. I have done mine 3 times in 230K miles.

 

The IAC is mostly an idle thing. Stuck wide open it "might" be enough to cause lean issues. I wouldn't worry about catastrophic damage. But on the other hand I would fix it toot sweet.
Got to go for the night.

 

Thanks for hanging in there and all the good advice DP. Husband is giving me a crash course in the driveway right now on all the major "stuff" under the hood. Have learned a ton already, just identifying what's where.

Have a good night DP.

 

One last thing. I'm sure someone has mentioned cleaning the MAF (mass airflow sensor). It and the intake air temp sensor are in the same little part and cleaned at the same time. Takes 10 mins with a screwdriver. Both sensors can have an effect on idle speed/stability. If you need the location and technique, I can get a pic up tomorrow.

 

I have to ask the unasked question here, was this truck running this bad before you got it rebuilt? does any of this seam familiar to how it acted before?

what I mean by that is, I am thinking that the truck was running bad before because it had several issues going on and the blocked injectors and hole in the piston was just part of the solution and now you still have this original "gremlin" still to deal with that was part of the reason for the truck to be running bad before it burned up.

 

Nope. It sure didn't start instantly before, but it didn't hesitate to start for as long as what it is sometimes now either. Speed it started at before was somewhere in between the super fast and super slow starts we're seeing now, but the main difference between then and now is before it was consistent in it's starting speed, whereas now the speed it starts at seems dependent on some unknown culprit.

Also, it definitely did not idle weird before. I am CERTAIN I would remember if it had, cuz I was the one driving it mostly and would have noticed/remembered if it nearly died at a stoplight or something like that. DEFINITELY.

You do raise a great point though Keakar - you actually prompted us to go back and watch the horrifying videos (3 of them) we took when starting it at the beginning of this whole nightmare, back when we were still clinging to false hope that the god awful engine noise would magically disappeared. It was really awful to watch those again! But in doing that, we realized that it did NOT start instantly before, but also didn't hesitate for as long as it SOMETIMES does now.

 

YES PLEASE!!!!!!!!!!!! THANK YOU SO MUCH! You've given us tons of help today (as well as everyone else too - thank you!!!). Just reviewed all of the helpful posts you guys have given us today w/husband, and now we're headed out into the cold to do some tinkering around, complete w/a nice large glass of wine. Thank you guys!!!

 

Hmm I gotcha. Well sounds like they've attacked the fuel system properly. But as you said, I still wouldn't rule out a fuel pump. Not sure if the fuel pressure regulator or fuel pump fixed mine (since I did them at the same time) but if I had to guess I would say fuel pump. Those fuel pumps do some weird things when they are dying. Since you did the swap, have you verified or had the mechanic verify all the vacuum hoses are connected in the proper location and all sensors are connected properly? If you post a pic of under the hood I can look over it. I know I won't be able to see everything but I've been under the hood of mine PLENTY and might catch something that is in fact connected but connected improperly. Just a thought.