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

Hey there Mod. Husband checked timing with a light initially, and it was off the charts retarded. Then he did the light and jumper thing at the same time and it was 10, which was perfect. Something made those 4 starts that night seems significantly better - and the "stuff" that went on just before them was the new TPS the day before; the timing/jumper thing just an hour or so before; and the unplugging of that AFR controller.

Tuesday morning when we brought it home from the last mechanic, we did a 30 min hot start with controller plugged in and excessive cranking (what we expected). Then we unplugged the controller and did a 30 min hot start but it was excessive cranking (not what we expected, after the 4 decent starts that one night when controller was unplugged). That's when we took it to the guy that has it now, and told him we HAD thought the AFR played a part, but NOW we weren't sure (and described why). I'd meant to plug the controller back in before we drove over there. But in the hurry to get everything organized/prepared to take it to yet another mechanic, I forgot. When we arrived, my neighbor that came with to introduce me to the mechanic he's friends with offered to go under there and plug it back in for me.

Here's the weird part - when I talked to the mechanic a couple days ago, he said the worst start he's gotten out of it was the very first time he started it that first evening we brought it in. We got there around 2ish, then he never had a chance to look at it, so it sat parked for a good 4-5 hours - should have been pretty darn cold under the hood (ambient would have been in the low 50s that afternoon). He said it cranked for a good 20 seconds when he started it around 6:30 to move it inside for the night! Pretty sure the longest it's ever cranked for us was ~10 seconds. 20 seconds is a hell of a long time, and especially when it's cold! With the exception of once or twice, it's started good cold for us all the time!

The ONLY variable that was different that day was that the controller had been unplugged for a few hours midday, then plugged back in for ~4+ hours before he had that 20 second excessive cranking. Once he told me that, I told him now I'm back to thinking the gauge does have something to do with it. He said he was going to start investigating how the thing is wired. When we stopped by there yesterday, we saw that he removed some of those plastic panels that blocked the wiring behind the gauge. I haven't gotten to talk to him yet about whether he's seen anything "off" - my guess is he hasn't had a chance yet to read the various Innovate install guides, and would want to do that before making the call.

But, they are letting us bring it home for the weekend since they're closed anyway, and they are so close by. So we're gonna pick up now, then take back Sun night or early Mon. And we aren't going to "mess" with anything, but figure we can at least get a closer look at the wires, and compare them to what the manual says. And maybe do more hot starts with controller unplugged vs. plugged in to see what we can tell. Beyond that, we aren't touching anything - that's his job to resume on Monday.

I'm impressed that this guy has actually taken that stuff off and is starting to look at wiring as a potential culprit - he's the first one, and I'm starting to gather why - the wiring shit seems like a huge PITA compared to swapping a sensor, or a fuel pressure regulator, etc. It's a big old rat's nest of possible problems, literally and figuratively.

 

He's working on it for criminey's sakes, see previous post please!

EDIT: I do see your point - take the unnecessary out of the equation before reinventing the wheel. I agree. He's working on it, and is aware that we suspect it could be causing/contributing to the problem, and he has been the most open minded of any of the mechanics so far regarding it being a possible culprit. I'm going to trust his judgement on the order to do things/look at things in. He seems pretty on the ball so far.........which makes it nice for me to be able to back off and think about other stuff, and just trust him to do whatever he thinks is appropriate.

 

One more thing - I emailed the engine mechanic a few days ago and asked a bunch of very specific technical questions about the swap process, about the new engine, etc, and explained that we are still dealing with the misery of being without the truck and paying mechanic's labor charges to try to diagnose the hot start issue. I pointed out that any reasonable person has to at least consider the possibility that the issue was caused or is at least being contributed to by something that happened during the work they did, since the truck didn't have a hot start issue before that. I BEGGED and PLEADED with him to please email me back after talking with his techs that primarily worked on our truck, to give us answers to any of my questions, give us any details at all that they could remember, as far as whether there were any hiccups during the swap, any wiring that looked questionable, what diagnostics they performed and their results, etc, in hopes of providing some clues and getting the issue resolved that much faster and for that much less additional cost. I also asked him to please let me know the details on all of the parts they put in - meaning, new vs. used vs. rebuilt/reman, and their brands (OEM vs aftermarket, etc) and explained that our invoice doesn't show any of that information, and since we never received warranty info on anything, we're not sure if he put in used parts or not. And it would be helpful to know, because it only makes sense for current mechanic to question the function of a used or aftermarket part before questioning the function of a brand new OEM.

And no response. Really a stand up guy, huh?

 

OK, Taco's home.

It appears the AFR gauge is getting power from cig lighter as we were told by the mechanic that installed it. So we pulled the fuse for the cig lighter, and unplugged the controller for it under the truck also. Let it get hot, and excessive cranking. I'd assume by taking power away from it means we are also taking away any potential harmful effects from any potential faulty grounding for it, right? The grounding does look a little funky, but not outrageously weird. If so, it's looking pretty darn likely that the gauge is not in any way contributing to the problem. Gonna do one more hot 30 min start soon, just to feel 1000% sure we can cross it off the suspect list for good.

And if that's the case? Then our best hunch is it's a timing thing. That was one of the other variables that night that we had those 4 decent starts. So husband will do the jumper/light thing with the timing again after we cross the gauge off the list once and for all, then we'll see. But really starting to wonder if the knock sensor is faulty, and could be causing the weirdo timing stuff and therefore the starting issue. Gotta go back and re-read some of Bama's posts regarding this topic, and we're reading FSM pages regarding timing, knock sensor, etc. At least if we can cross some things off or get some more clues, it could be helpful to the mechanic on Monday, so feeling good that we are making some kind of progress over here. Plus, soon it will be time for a J & B, so feeling good about that too!

Happy Saturday TW, thanks for reading and thanks for sticking with us!

 

Husband did jumper wire/timing light thing 2x, and each time followed up with a 30 min heat soak start - and excessive cranking both times. Seems like timing may not be related to the problem.

So that leaves only 1 variable that changed just shortly before the 4 decent hot starts that night, which is the TPS being replaced by dealer the day before. Also, I assume they disconnected the battery when they swapped that sensor, so not sure if somehow disconnecting the battery could have some relation?

Gonna also try 2 starts with hood up for full 30 min, just to be totally sure that it makes a difference, since that's something we've noticed off an on but never taken the time to be totally sure of. New mechanic had asked me about that.......

Also thinking about calling and see how much noid lights cost at Harbor Freight.

 

Whoa! OReilly lends out noid lights for free! Had no idea! Wonder how difficult it is to set those things up? We assume too much fuel is going in during excessive cranking, based on angel mechanic's last noid light test when he said the light was crazy bright, and also because he'd said holding pedal down during what would normally be an excessive crank start allows it to start right up. But it would be nice to see for ourselves what the noid light test reveals, in case anything has changed since his observations, and especially if they are simple to use AND free to borrow. Anyone ever use those, or know how difficult they are to set up? Also, I remember someone along the way (not on here) said an oscilloscope is a better method of checking injector pulse over noid lights. Anyone have thoughts on that?

About to start it after hood's been up, just to verify that the heat soak is indeed the common factor.

Also going to do a start or two with pedal down, just to verify that throttle being held open corrects the crank time.

At least it's a nice sunny day to be monkeying around with some free testing, and at least we are able to cross some stuff off the culprit list, even if we aren't able to identify the culprit! At least whatever we can cross off will help our mechanic somewhat....

Hope you're enjoying your weekend TW!

 

Started pretty good (not perfect but decent) with hood up for full 30 min since last started. Repeating that same test again now. The weird thing is Scan Gauge showed that IAT was 82 when we started it, even though the hood was up for that 30 min period prior to the start. Seems to me like that number should have come down more with the hood up the full 30 min, because ambient right now is 55. And also seems that perhaps whatever the IAT number is has no bearing on whether excessive crank or not, because normally when it's 82 (like it was now) or higher, we have excessive crank time. But since we didn't this time, seems like it's some other heat related issue, because temperature is the only thing that would be impacted by having hood up. Hmmmm.

 

Wondering about this. We never did swap the ECT sensor - just tested it with crappy Harbor Freight tool. But where is this water temp sensor?

 

Started pretty good on 2nd time around with hood up for full 30 min after last running. Thinking we can say for sure on that factor.

Just picked up the free loaner set of noid lights from Oreilly, but step 1 says to remove injector harness - thinking we will likely chicken out on doing the noid lights!

Gonna do 2 starts with accelerator held to floor just to verify that doing that still causes normal starts at times that would have otherwise been excessive cranking. Almost time for some beers too!

 

OK, two starts with accelerator pedal to the floor during times that would normally be excessive cranking. While it did definitely start better/faster than it would have otherwise, it wasn't instantaneous like we expected. There was some additional cranking, then VROOM all of a sudden once it turned over, both times. It started better with the hood up - more normal time and sound to it. Hmmm. Anyway, husband is looking at FSM on how to test the connector to the igniter next. And we are rechecking ground wires as well. And also thinking of checking battery voltage during excessive crank times. Stay tuned!

 

Looking back over this post for ideas......

EDIT: Husband is monkeying with fuses a bit, then time to quit monkeying and get some food! We learned a few things today though:

1) AFR is not the problem
2) Starts best with hood up
3) Starts OK with accelerator held to floor, but not as well as when hood is up
4) Still not 100% sure whether timing has something to do with anything, but doing the jumper/light thing did not improve starts at all.
5) Thinking that pending TPS code that came up AFTER new TPS was put in is our best clue for now.

More monkeying tomorrow, have a good night all!

 

Jen. 2 things:

1. on the 1st gen Tacoma, if you have a 4wd automatic truck ECU, and you get another 4wd automatic truck ECU and plan to swap them out, there is no programming required. That are a simple swap-out item. They just have to match in engine, transmission, and if 4WD or 2WD.
2. Remind me again, the MAF sensor you have in the truck right now, it is a brand new unit, or a used unit? If it is a used unit, do me a favor please and email me your name and address.

 

Yup, good one. Keep an eye on the batt. It's getting a workout more than usual, as is the starter.

All this time, the battery has not been disconnected that you know of?,,So no for sure reset of the Ecm?

 

Thanks for the input Bama! Good to know about the ECU swap - I wasn't sure as to whether the TRD Off Road difference caused a need to do the "flash" thing, but it sounds like it doesn't. Very good to know!

PM'ing you now! The MAF is a used part. Initially my husband thought it was a different one than what was in the truck prior to the engine swap, but now we honestly aren't 100% sure. Either way though, being that it has an abbreviation written on it that stands for a local used only parts store, I am certain it is used. And we did do a very basic test from FSM on it that yielded results in spec, but I'm not convinced from just that basic test that it couldn't be all or part of the culprit here. Especially after seeing that IAT value stay up at 82 after sitting 30 min w/hood up during a time that ambient was low 50's! Are you considering a cookie/MAF swap? That swap works very well for me if it does for you!! Thank you!!

 

Mod, ya think checking battery voltage during excessive crank would tell us something? We're thinking about doing it today, and since it's free and won't hurt anything, seems like why not. But I'm confused whether it would mean something if the voltage is off during the cranking? Do you know? I know for sure the battery itself is in great shape - it's got the appropriate volts, 14 I think?

Angel mechanic reset the ECM on one of the first few days of February, but I'm not sure HOW he did it - whether he just disconnected battery or did something else. And I'm not sure if other mechanics disconnected it since he reset the ECM, but I think they probably did. I know when the dealer replaced the TPS, they said they cleared the DTC's (P0120 for TPS) but they never told us HOW they did that. And I'm pretty sure the mechanic that told us to replace the fuel pump early in this past week DID disconnect the battery, because the mechanic that has it now noticed that one of the cables to it was loose. Plus the "replace the pump" mechanic had told us he found a pending code for TPS (after TPS was replaced), but that pending code is not showing up on Scan Gauge now, so somehow he got rid of it. We haven't disconnected the battery ourselves, but were considering doing that today, just to see if any change in anything afterwards. Ya think there'd be any point in doing that? There's no pending codes at the moment, so I don't think we'd wipe out any data......

We were going to test the igniter per FSM yesterday, but the connector for it is really tight on there, so I think we're gonna chicken out on that and maybe ask the mechanic that we're working with now to do it when we take it back to him tonight or tomorrow morning. Same thing on the ECT sensor - hard to get at and very tight connection, so we'll ask him to test it. And if he hasn't yet, I'd like him to test the wire to the TPS - there's a reason we got a pending TPS code AFTER TPS was replaced.

The thing I am happiest about now is knowing FOR SURE that we can cross the AFR off the suspect list. While it would have been nice to have finally found the culprit, I'd rather know it's not it than keep speculating if it is or if it isn't. Husband is recalibrating it now, and he got the hole under the truck where the wires for it come into the cab plugged up nice and tight with the appropriate plug from the dealer and the wires going through the middle of the plug, so at least now we don't have to worry anymore about water splashing up to the underside of the carpet through that hole! So disappointing that those guys left details like that so sloppy - a critter could have crawled through that damn hole! And you know in our rainy climate we would have had a flooded passenger floor in no time without that being plugged up!

Does anyone know of where we could find a diagram of all of our ground wires? I found a few things in FSM, but nothing that clearly spells out where ALL of them are. I know angel mechanic said he checked them all, but still seems worth triple checking, since it's free and easy enough.

Husband still thinks it's an EVAP issue. He heard the charcoal canister clicking again yesterday. I remember DP posting a way to check it's function, by plugging one of the lines to it or something. Going to go back and review that post. Also, husband was thinking about removing gas cap during an excessive crank start, to see if relieving that pressure had any impact on the cranking. Ya think that would be an indicator of a possible EVAP issue if it altered the cranking at all? Is it safe/OK to start it w/gas cap off (other than getting a code)?

Alright, gonna go gear up for another day of DIY testing and inspection! Sun is shining, temps are nice and warm, and cold Hefeweizen and lemon in the frig - gotta find the positives in this disaster, right?

Happy Sunday TW!

 

Hey jen, just wanted to point out your IAT will stay pretty high for quite a long while(not saying there isn't a problem) you gotta figure that motor is several hundred pounds of heavy metal and several quarts of screaming hot motor oil. The engine temp is much hotter than the water temp, so when you see 195° on the SG the motor itself is much much hotter. It takes hours for that heat to dissipate, put your hand on that block hours after you've heated it up. It'll be very warm still. I understand the MAF istnt on or for that natter really even close to the block but there is still a lot of heat coming off that bad boy. Then figure that intake tube is connected to the TB/top of motor, so all of that heat will keep the air in the intake tube nice and hot regardless of hood up or not. The MAF/IAT is quite well insulated from outside air temp due to it being inside the tube then insulated by a bunch of hot air. Just something to think about so ya don't get to hung up on the IAT.

 

Thanks man, that's a good point. Actually we were discussing that yesterday with neighbor, and when I told him how it seemed weird that IAT was still 82 after a 30 min period, he was like, eh, not so much really. So with your comments, that makes two votes that's not weird - I'm goin with that line of thinking. Thanks!

 

Just took it back to mechanic, and updated him on our results from messing around this weekend (hood HAS to be down, otherwise it will start pretty well; pulled cig fuse to totally disable power to gauge yet still bad starts 2x; starts fairly well with accelerator held down during crank time but not perfect - best with hood up; etc). Put our donor ECU in cab as well as new O2's and told him feel free to try swapping either/both if he wants to.

Right now his best hunch is something a little off with spark. He's noticed that the spark timing seems just a wee bit off during cranking, so he's questioning the crank sensor or something to do with the crank wheel (I think?). Told him crank sensor was replaced with a cheapo aftermarket by angel mechanic, and he felt like an OEM would be better - might make a few calls to check on that today........

Told him we chickened out on testing igniter cuz connection was very tight, but some folks have told us it could be a possible culprit. He said if we could track down a donor igniter to try it might be worthwhile.

Anybody have a donor igniter they wanna swap for cookies?

 

So your set at 10° initial right now,,,cold. So,, hot and cranking is probably where he is seeing the spark being off or not right, it is some what safe to surmise. And that would make sense with a long crank to start when hot.

Maybe, since it is new,,you could get away with a slightly later spark. Say set the initial at 8° or even 9°. The range is 8°-12° and I would imagine its that way for different altitudes, regions, fuel qualities(maybe), ect.

It could possibly need 11° on that initial(the other way,,earlier spark). As per the latter stuff, the computer is adjusting what it needs when it senses a hot engine, but it doesn't mess with the initial setting per say, because that is mechanical. I have no idea on how much control the Ecm has on pulling timing when and where needed,,maybe someone can chime in with the tech specs.

There is the TB blade setting that needs to be set right for hot and cold both? I believe,,and hopefully it has been checked many times for correctness.

One click is all it takes sometimes.

Throwing some thought out,,to generate more and see what folks have to say about it.

 

I'll say this, there is no ign timing adjustment on a stock 3.4. You can check it but you can't adjust it.