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

I'm still thinking leaky injector is possible too, but just FYI, here's what the injector place did -

Ohm tested, flow and spray tested, then cleaned, then flow and spray tested again. Decided 2 were failing and replaced them with 2 "new" rebuilt injectors. I'm sure the other 4 would have gotten whatever new stuff they should have, because I'm pretty confident in that guy's work from his reputation and in talking to him when we picked them up. But still, who knows? Strange stuff happens sometimes.......

The first thoughts the dealer tech had was vapor lock. He said the thing that stuck out to him as being really important is the "Raising the hood" bit. Sounded to him like the fuel in the fuel line or fuel rail is boiling into a vapor due to excessive heat buildup, and he'd want to visually inspect that all the fuel lines are secured and isolated from heat sources, and that if there are any improper routing or mounting that could be inducing extra heat, he'd want that to be resolved. That all sounded very logical to me, definitely.

But not ruling out injectors either TenBeers!

Hetkind, I think the rough idle has improved since we really noticed it bad back in Feb. We got the TPS code and replaced the sensor, and I'm guessing that may have helped it smooth out some? I do still see the needle bounce just a little bit, a few times after we start it, and it seems a little worse after a rough start. It smooths out after a few minutes though, then I haven't noticed it during stops while driving since those few times in Feb when it was really bad (before TPS was replaced). I think Eric did some tests to rule out vac leak, but I will double check with him. Thanks for chiming in!

 

HOLY CRAP GUYS!!!

The dealer tech that I've been emailing with said he's been talking to his buddy there about it, and they'd be willing to look at it and would only charge diagnostic of $100 if they were able to identify the problem, otherwise no charge. He said it sounds like an interesting problem, and they like a challenge. I'm thinking we should give it a shot! He said they'd want to keep it for at least a week, but I'd be willing to be car-less for one more week for this. It's a chance, it's a ray of hope with zero risk, right? What do you guys think, is there any reason not to give this a shot?

 

sounds like a side job "off the books" and mechanics do this all the time to make extra money but be aware you have no protection if the truck gets wrecked or something is broken or there is damage to your truck so be aware the dealership is not going to be paying for any vehicle or engine damage that may result from their work. plus if they get in a wreck driving your truck you are on the hook for them and whoever they hit because its not a dealership repair so its all on your liability. course that was no different then the neighbor mechanic but just to remind you.

as long as you understand that they are using you for a project challenge to play around and experiment on your truck and may or may not be experienced at working on stuff like this.

im of two minds on this, one says anything they might check has already been checked and rechecked so what more could they do, and the other says they might just solve it and have already agreed on the price to fix it so what have you got to loose.

I would feel better talking to their boss first to get his ok with them working on this on their property on these guys own time, so at least there isn't a big stink over what the hell is your truck doing on their lot as a liability risk to them when they are not "officially" working on it.

 

Thanks for looking out for us Keakar!

I'm pretty sure this would be a legit situation, just like any other time someone would take a car to the dealer. It's just the advantage to this is having somewhat of a personal connection with this guy, and talking to him about the details of what's gone on with the truck before even bringing it in. AND, he used to have a 98 Taco, just like ours, back when he was a tech (he transferred to another dept years ago), so he would certainly be very, very familiar with how things should look/be routed/mounted under the hood and under the truck, which makes me hopeful. We are tempted to give this a shot. Might wait a week or two to have some time to observe how it's behaving now, and be sure we are giving them the best description of the symptoms we possibly can if we go ahead and take it there. Feeling pretty good about this plan! The guy has been extremely nice so far, very interested in learning the history of what's gone on with the Taco, exactly what the symptoms are, etc.....feeling hopeful!

Happy Wednesday TW!

 

Random question - has anyone ever heard of your car insurance covering a free rental car while your car is being repaired? A neighbor was telling me any reputable major auto insurance company does this for customers with full coverage, and that they'd just require your mechanic to fax them something saying they will have the car for at least 24 hrs for repairs. Sounded too good to be true? All I've ever heard of is getting a free rental if you are in an accident and need repairs as a result. Just curious if anyone else has ever heard of anything like this.......

 

The thing that gets me is I've had the same problem as you and I've done a ton of looking on the forums as you have,,, this problem is very prevelant from what I've seen.

Mine still does it, but like I said my FSM (95) says in the diagnoisis to check my VSV function for the FPR,,, anyway we've been down that road, you said your's doesn't have a VSV. I still haven't fixed mine, but it's been because I very seldom drive like that and let it sit for the 30minutes or a little less like you do, but mine does the same thing except mine is the 4 cyl.

Something is triggering this stupid problem and I agree it's vapor lock, BUT think about this,,,, why didn't it do this with ALL these vehicles that have this problem when they were new,,, the dealership would've been over run with this problem on new cars,,,, just when they get a little age on them does it seem to appear,, like myself .

Been dwelling on this for a while and I do plan to try and solve mine later on after I deal with this cancer health problem I'm having at the time being...

Hope you find it LMTL.

 

Oh wow, I am so sorry to hear that Pulldo. Best wishes to you on a speedy recovery!!

I agree, it is very strange that sooooooooo many folks report this problem, or some similar version of it. And few ever post a positive conclusion to it, so you don't know how many found the fix but didn't post, vs. how many just live with it, vs. how many gave up and got rid of the vehicle. It's very frustrating to feel like so many deal with it and yet seemingly no one has found the fix, save for a handful that had MAF or fuel pump fix it. And you're right, it's strange that if it was a flaw in the design, then why would the problem only appear with some miles on the vehicle? I've seen reports from people having the issue as early as ~50K on the clock, and some have been on Toyota trucks that are only a few years old! Crazy. I'm really starting to believe that we just got unlucky and received an engine that is prone to this strange starting problem somehow......

We have a Vapor Pressure Sensor, a VSV for EVAP, and a VSV for Vapor Pressure Sensor. We tested all 3 per FSM here at home, as well as our charcoal canister, and all tested normally. Then we even tried our donor canister anyway, and no change. And I'm 99.9% certain we don't have any other VSVs (like one for FPR), or EGR stuff. Real bummer though, because just the terminology alone is enough to give you hope - part names that begin with the word "vapor" - seems like a logical culprit, considering all symptoms fit "vapor lock" perfectly. I even considered calling around to see how much for a new Vapor Pressure Sensor, then if cheap enough, perhaps trying it just for giggles.

My very best to you in your fight against cancer, and I also wish you the best in finding the culprit to our annoying mystery problem! And I absolutely PROMISE I will be sure to share the solution with you if I ever find it!!! Least I can do after the support you've given us, while you are dealing with far bigger things!! And thank you for sharing your thoughts!!

EDIT: One other thought I've been having. I've noticed A LOT of 3rd gen 4 Runner owners reporting the problem. We thought about getting a manual on a 3rd gen 4 Runner and glancing through some of the likely culprit stuff, to see if there'd be any clues.....although seems like a lot of reading for a very very long shot! BTW, does your FSM have that page that lists a symptoms table, then the top two culprits to check first pending the symptom? Is that where you read about checking VSV for FPR? Was there another item it said to check also?

 

I had a 3rz powered taco that had the hard start issue also. It was pretty embarassing at times.
I blocked off the egr, changed a cracked exhaust manifold, replaced the cat converter to a magnaflow oem replacement, put in a small less restrictive muffler (glasspack) and changed both o2 sensors- my problem was fixed after all that- Not sure which one fixed it as i was just addressing the whole exhaust system on a 300k truck... I wasnt even really trying to fix the hard start at the time but after all that it was gone.
My personal opinion is that it was the egr causing the hot start problem in my case, i dont think her vehicle has one though.

 

Hmmm. Food for thought here Knuckle, thanks. I've wondered about the O2s. We actually ordered 2 off RA for a decent price, both Denso, but wound up returning them because our mechanic felt sure that it wouldn't be that, because of the whole open/closed loop thing. Since then, I've regretted that more than once, since they really weren't a ton of cash anyway - wish we woulda just put 'em on. And I've wondered about the cat too.....engine dudes said they checked it and said it was "low flow but OK" - I think they said they checked the backpressure maybe? But most recent mechanic said we'd have other weird driving issues if it was that. But cracked exhaust manifold. Hmm. I don't even know where that is exactly or what it looks like. But FSM to the rescue!

That really is one very cool thing about this - how much I've learned! I didn't really realize it until my neighbor was working on his Explorer the other day. With just a quick glance, I was able to identify ~10 major parts right away. On a Ford. Was a pretty cool moment, especially since it was the former army mechanic neighbor - surely he was impressed!

 

OK, just had this crazy thought. Bear with me here guys, it's a pretty "out there" theory......

Ya think our new engine DOES have an EGR valve, even though our truck isn't s'posed to have one?

Or, ya think the new engine came off a truck that had one, and now it's like, where the hell is my EGR valve?

I know, a little out there. But, thoughts?

EDIT: Folks w/EGR valve - where the heck is it located? What purpose does it serve?

EDIT #2: Reviewing EGR diagram in FSM, gonna pop hood and see if I can identify general area........

 

Not real sure about a 3.4 but on a 3rz its by the throttle body then has a tube that goes to the exhaust manifold.
Honestly if it were me I would just buy ALL new sensors and replace them one by one and see what happens.
I would just get discount ones on ebay if it were me, i think I gave $14 apiece for the o2's on my taco, $20 for the maf, etc. Generally by looking at the sellers feedback you can tell if they sell junk or not.. Even go used to save a buck-

 

I hear ya Knuckle, about the sensors thing. We are kind of already heading that way anyway, without even intentionally doing it! We've done the ECT, TPS, Cam, Crank......getting to the knock sensors would be a real bitch......but we could still do those O2s and might.

Tried looking around for EGR area, but no dice. Will take another look near TB (thanks Knuckle!)

EDIT: Our MAF, even aftermarket, is way super expensive. Just the style of it makes it super expensive for some dumbass reason. But in thinking more about our donor, surely it can't be our MAF. Cuz if our donor didn't have a hard start issue, then how could it be that if no change with either MAF on the truck? That's my logic anyway.......

 

Pretty cool thing just happened! Neighbor's mechanic friends are working on their Kia (changing clutch) and came over to look at the Taco/hear about it's problem. Pointed out the exhaust manifold and the little heat shields on it to me. Wonder if putting beefier heat shields on there would change anything? Guess I'm mostly wondering if there'd be any harm in trying it, and how difficult it would be. Thoughts?

 

I still think injectors. I think I remember your fuel trim numbers being high, indicating it was trying to lean things out quite a bit. Sensors are telling it that it is running rich, so it is trying to trim things back.

Basically you have fuel, air and spark.

Air is pretty simple: You have a clean filter, MAF has been tried, checked for vacuum leaks, TPS seems OK as well.

Spark is a little more complicated, but issues would show up on the diagnostics or a CEL.

Fuel is a little more tricky. Diagnostics can tell you that the signals are happening at the right time, but the actuators have to be working properly.

If the original heat shields are on and the fuel lines are run in their original locations, I wouldn't worry about adding any more shielding.

 

That is so funny TenBeers, not even 10 minutes ago I called my husband and said I wanted to pull the injectors again! I started thinking, what if the engine guys sprayed them with carb cleaner and destroyed them? That would explain the poor results from Inj. servicing #2 only a month later. And could explain the starting issue too, as well as the fuel odor when we lift the hood just before a hard start. It's tempting to see if we could handle pulling them ourselves this time, and take them back to the place that did them last. Pretty sure he wouldn't charge if any had issues, then if any did have issues, it'd be tempting to cough up the $1K on a brand new set, to be assured we never have injector problems again. But if he found none of them had problems, we'd have to pay him like $150 or something. But then we'd definitely be able to stop questioning the damn injectors, once and for all. Which seems worthwhile, especially if we could pull the labor off ourselves and save that expense.......

I just read an FJCruiser thread where a guy had same problem, and injectors were his issue. Kind of an interesting read:

http://www.fjcruiserforums.com/foru...247273-extended-crank-starting-problem-8.html

 

Quick question? Tossing darts here, but have you ever opened the fuel cap before one of these hot start test? I don't know if it can make difference, but am curious just the same.

 

We haven't. We thought about it but never did. Ya think we could just remove it and leave it off while cranking during an expected hot start? Just to see if any diff?

Thanks for the idea!

 

Not gonna hurt a thing. Just tighten it before you go for a drive, you will get a CEL if you don't.

 

BTW, changed the title, hoping to pick up more traffic.

Anyone new viewing this thread:

The problem is:

Extended crank time to start (~5 seconds, up to 10-20 seconds occasionally) 30-60 min after last running at full temp.

• Cranks longer/more abnormally if truck was driven 30-60 min prior, as opposed to just being idled 30-60 min prior.
• Starts great cold.
• Starts great if started within 5 min of when it was last running.
• Raising the hood for at least 10-20 seconds prior to cranking allows it to start normally.
• Depressing the accelerator while cranking helps it start more normally, but not as normally as raising the hood allows.
• Runs great, except occasional mildly twitchy idle for a few minutes after first started (this was worse before TPS was replaced).
• Engine sounds good/quiet; very powerful; mechanics said compression is good.
• Only code we've gotten was for TPS - replaced it.
• Engine replaced in Dec; did not have this problem before that.
• Just about every part on the truck, except the steering wheel, has been replaced. Only exaggerating a little bit.

 

Gotcha. Trying this, thanks K!