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

Yeah! That sounds like a dream come true, to think about stuff like that instead of a hot start problem. Wow. Almost can't even visualize that.

Actually, when it comes to stuff like that, our Civic needs a whole lot more attention to that kind of stuff than the Taco. That poor little beast is just a cosmetic nightmare inside and out, head to toe. Dog ate the plastic drink holder when she was a puppy; driver's seat upholstery is ripped so bad that the foam is slowly crumbling out of it; paint is peeling all over the poor little car, on and on and on. But that car is truly a beast - it just keeps on going.

I was just thinking about how resilient that car is - I assume the Civic has fuel injectors too, right? We've never done a thing with them and the car is 22 years old with 225K. Wonder if the design of the Taco injectors is just poor or what? I know my parent's Ford Ranger needed it's injectors replaced a few years back once it got up there in miles/years. Wonder why there's such a difference from one vehicle to another as far as the injector's neediness?

 

I feel for you on all this Jen. Your blood pressure must be sky high these days. lol. I wish I could offer more suggestions, but at this point, I wouldn't want to add to the mess. I wish like hell that I was able to come up and look at that. Hearing that a shop, and even less a DELAER that won't look at or test a wiring harness issue? WTF? When I run a diagnostic process for ANY code, one of the things I check every time is the harness, so that I don't accidentally sell a customer a sensor, when it was in fact a bad harness, terminal, or connector. I don't get that at all. Jesus WTF has happened to techs these days? I know I wasn't the one who trained any of those knuckleheads!

 

[FONT=&quot]11/30/14: Piston hole – no CEL at the time, but we did get CEL 2x in August that went away with tightening gas cap 1st time, and with replacing gas cap 2nd time. Never checked codes. Towed to Toyota, they said we needed a new engine.[/FONT]

[FONT=&quot]12/16/14: Towed to engine mechanic to have 5vzfe dressed long block installed, as well as power steering pump, drive belts; and to diagnose & repair cause of piston hole and alert [FONT=&quot]us to anything else found that they would recommend replacing/repairing[/FONT].[/FONT] [FONT=&quot]Engine was replaced at mileage of 194,856.[/FONT]

[FONT=&quot]12/26/14: Engine mechanic said injectors came back with 2 failing (couldn’t remember which, no report provided to us). We asked him to replace fuel filter and agreed to have AFR gauge installed, and he said 2 failing injectors would be replaced; the other 4 were OK and would be put back in.[/FONT]

[FONT=&quot]1/2/15: Engine mechanic emailed us about hot start/excessive crank issue, which truck did not have before piston hole: [/FONT][FONT=&quot]"I got the engine in and running, It runs great, the wide band o2 gauge looks like it is running good at idle and under acceleration, no lean condition. I am having one issue, when warm after a very short stop, 3-4 minutes it fires right up but when warm if it sits for 30 minutes it requires excessive cranking. The cold start fires right up. This indicates to me that it is losing fuel pressure in the fuel rail slowly. Firing up good cold it has the added cold start injector but warm after 30 minutes the pressure bleeds off but the engine is still warm. I will test the fuel pressure regulator and the bleed back on the pump and get it dialed in to fix the issue. Like I said the engine runs great and sounds great, we will get this issue figured out."[/FONT]

[FONT=&quot]1/6/15: Engine mechanic [/FONT][FONT=&quot]said he's confident it's the fuel pressure regulator because when he bleeds back on it, it's in excess of what's "spec" for it. He said he was confident it wasn’t the pump because he did some tests on it and fuel pump problems are rare. I asked if he thought the injector issues were caused/contributed to by the regulator problem, and he said no, cuz it was 2 of them and not all 6.[/FONT]

[FONT=&quot]1/9/15: Engine mechanic told us to pick up, said hot start issue was fixed. He said to turn key to “on” position and wait for red light associated with AFR gauge to stop blinking before cranking, to allow wire to warm up. We did this throughout, but it had no impact on the excessive cranking issue when truck is hot (~30 min mark).[/FONT]

[FONT=&quot]1/10/15: Took back to engine mechanic because hot start issue was still present, and even cranked excessively at the 2 hour mark that morning. Replaced air filter with one from dealer just before, but no change. We asked them to inspect for an EVAP issue/vapor lock; they said everything related to that looked fine.[/FONT]

[FONT=&quot]1/13/15: Picked up from engine mechanic. They said they’d found our IAC valve stuck (couldn’t remember whether open or closed) so they cleaned & lubed it and felt the hot starts were resolved. Idle seemed low after this.[/FONT]

[FONT=&quot]1/16/15: Took back to engine mechanic because hot start issue was still present. They blew dirt out of a charcoal line and tested IAC valve; tested within spec. They swapped IAC valve with used one to see if any difference. Idle seemed high to normal after this, and would occasionally jump around a little bit.[/FONT]

[FONT=&quot]1/19/15: Called engine mechanic to report hot start issue still present, said we were thinking of trying to sell truck or take to dealer, asked if they had any ideas. They said they’d try to think of something and call us, but never called us again. Took to new mechanic that night.[/FONT]

[FONT=&quot]1/23/15: New mechanic replaced fuel pump.[/FONT]

[FONT=&quot]1/25/15: New me[FONT=&quot]chanic[/FONT] thought he saw leaky injector(s). Sent them to a professional; all 6 had “fair” spray pattern/low flow prior to cleaning; 2 were deemed failing after cleaning on 2nd test and were replaced (see report).[/FONT]

[FONT=&quot]1/29/15: New me[FONT=&quot]chanic[/FONT] put injectors back. He did a noid light test on them and noted no pulse initially during hot start/excessive cranking, then finally light would become bright when truck started.[/FONT]

[FONT=&quot]2/1/15: New mechanic noted dented cam sensor and said he barely got any reading on it; cam and the crank sensor were replaced. Afterwards, he repeated noid light test and said it was very bright during hard start, as if too much fuel going in.[/FONT]

[FONT=&quot]2/2/15: New me[FONT=&quot]chanic[/FONT] reset ECU before flying out of town, in hopes of codes being set while ECU relearned sensors – he wanted us to drive it as much as possible while he was gone to accomplish this. He still felt it was a fuel issue somehow, but also felt he’d combed over the truck so much by then that he’d eliminated nearly everything but the ECM as the culprit. His hunch was that for some reason, the ECM was not giving the right orders to the injectors.[/FONT]

[FONT=&quot]Throughout the time new mechanic worked on it, he noted when throttle was held open during hard start, it started right up. He noted cracked hoses that were reinstalled with new engine (he replaced them); a leak in a fuel return line (he replaced it); intake manifold was left filthy & with debris in it (he cleaned it as best he could); stripped bolt where fuel pressure gauge normally goes (he tapped in to check pressure under truck by fuel filter instead, fearing he’d cause a leak if he opened that up). [/FONT]

[FONT=&quot]The few days here and there that we had truck home up to this point, we smelled an odor from the truck after it had been driven or was running – possibly special bearing oil for new engine (we changed oil/filter to 10W30 on 2/7 when we had 500 miles on new engine as instructed); or fuel odor, or a burning rubber odor? We also noticed we could hear the CD in the CD player spinning, even when the music volume was turned up, which we’d never noticed before engine swap and related work. [/FONT]

[FONT=&quot]2/6/15: While running errands and therefore having multiple hot starts in a short period, noted very rough idle and also truck lurched/hesitated twice while driving. That night, it also had excessive crank time even after sitting for 4-5 hours (normally hard starts only occur at 30 minutes, and occasionally at up to 45 min to an hour – but 30 is consistently bad).[/FONT]

[FONT=&quot]2/7/15: We replaced plugs (please see numbered old plugs in glovebox that engine mechanic had put in – they were a mismatched set); coil packs; plug wires; thermostat, and changed oil. Thermostat jiggle valve was set at 6 o’clock on old one and was again on new one per FSM. Also, we checked timing with timing light and it was retarded – [FONT=&quot]neighbor[/FONT] verified this.[/FONT]

[FONT=&quot]2/8/15: Drove ~30 miles (many of them highway miles) to see if any change in rough idle; idled smoother but no change with hot start issue. Reset timing via jumper wire method per FSM (please see attached sheet from FSM), then rechecked it with timing light and it looked correct.[/FONT]

[FONT=&quot]2/10/15: During a hot start/excessive crank with hood elevated just slightly, got a check engine light and code for throttle position sensor (P0120) – please see sheet of freeze frame PIDs that recorded on our Scan Gauge. Idling very rough. OHM tested TPS; tested within spec per FSM.[/FONT]

[FONT=&quot]2/12/15: On our way to Toyota, CEL again for same code P0120. They said no need to test TPS or wire to it, and said replacing TPS would solve the problem, which we agreed to. They recc’ pulling injectors again and checking fuel pressure again, we declined.[/FONT]

[FONT=&quot]2/13/15: We reset timing via jumper wire method per FSM while checking it with timing light at the same time, after husband discussed this with Toy[FONT=&quot]ota[/FONT] tech (please see attached sheet from FSM). Then rechecked timing with light after and it was correct. Then unplugged AFR gauge controller (little black box mounted under truck next to cat), let truck get hot (~30 min mark after last running) – started almost normally; repeated again, same result; repeated at 45 min mark, same result; repeated again at 1 hr mark, same result. Plugged controller back in, waited 30 min til truck was hot – excessive cranking. We noted open hole where AFR gauge wires come into cab underneath truck just next to passenger door; missing bolt from one of the two OEM O2 sensors[/FONT]

[FONT=&quot]2/16/15 – Called engine mechanic to ask about AFR gauge installation process. The person that installed it said he did NOT wire to our ECM; thought he used cigarette lighter as its power voltage source; grounded it to our dash, “did not add a ground all the way out to the battery, because everything in our truck grounds right in our dash, so its grounded right behind the gauge”; used the “quick start guide” for install instructions that came in the box (did not use 20+ page guide from manufacturer’s website); said everything was straightforward about install.[/FONT]

[FONT=&quot]2/20/15 – Plugged AFR gauge back in and recalibrated it. Took to new mechanic and explained difference in how truck started with AFR controller plugged in vs. not – asked them to duplicate this and to see how AFR gauge was wired/getting power from. They called later and said there was a pending code for TPS; we told them TPS was replaced by dealer a week before.[/FONT]

[FONT=&quot]2/23/15: Mechanic at that garage said they did not duplicate the issue and also were 100% certain that AFR gauge had nothing to do with difference in how truck started for us, even if it had been installed incorrectly. Said replace fuel pump because PSI was 51, and spec is 38-44. Said no change in PSI even when fuel pressure regulator was disconnected, said no obvious signs of leak in return line but hadn’t thoroughly inspect it yet. Said voltage was normal; so didn’t believe that could be the issue of why the pump was putting out too much pressure. Checked pressure under hood where it’s normally checked where stripped bolt is; said it didn’t cause a leak (like other me[FONT=&quot]chanic[/FONT] had been concerned it might). Said they tested our TPS and it tested fine; did not test the wire from TPS to ECU. We declined replacing fuel pump.[/FONT]

[FONT=&quot]2/24/15: Picked up from [FONT=&quot]that [/FONT]garage. Attempted to duplicate what we noted on 2/13 with difference in how truck started with AFR controller plugged in vs. not; equally excessive cranking when hot in both scenarios, so now uncertain whether AFR gauge plays a part in the starting issue or not. [/FONT]

[FONT=&quot]WE HAVE 2 NEW OEM DENSO O2 SENSORS, as well as the bolts/nuts that go with them. PENDING WHAT YOU RECOMMEND, WE CAN BRING THEM UP TO HAVE YOU INSTALL THEM, OR RETURN THEM.[/FONT]
[FONT=&quot]We also have a donor ECM if needed, off of a nearly identical truck (’98 Taco, 4WD, automatic; only difference is that one was not TRD Off Road). [/FONT]

 

Thanks Bama. I imagine it is sky high! It's put a serious strain on our lives, it just plain sucks. There's just not much joy or relaxation since November 30th in this home.

Got pulled over for speeding in our Civic a couple days ago (doing 45 in a 25 - oops!). Just a few minutes before that, I'd been told to replace the fuel pump by the last mechanic, then had to leave to pick up husband from work. Naturally, my mind was not on the speed limit at that point. I know people sometimes tell sob stories to cops to get out of tickets, but in this case there was zero "acting" to it. I started bawling my eyes out and begging and pleading with him, and filled him in on the nightmare with the Taco that just will not end, and that I'd just heard from mechanic #5 that I should replace an expensive part that had been replaced a few weeks prior. He let me go.

Yeah, I'm certain you didn't train these knuckleheads! But at least I'm feeling better now, because our neighbor's vote of confidence in the mechanic that currently has it means a whole lot to us, considering he sent us to the angel mechanic last. So I really believe this guy will get it, and maybe even through some "putting their heads together" with the angel mechanic when he returns, since they do know each other. They are good guys - not concerned about proving how brilliant they are or getting their egos stroked - they are the kind of guys that are focused on diagnosing the problem and repairing it, period. And they recognize the value in listening/reading the history from the customer, particularly in such a lengthy complicated situation as this one. Wish that were true of all the people that we've encountered since 11/30 - we might not be where we are today if that were the case. But this guy, and perhaps with some input from the angel - they will get it. I just know they will. They are good guys, I believe in their abilities and their determination to get it 100% right.

 

Bama, just reread your post from around 2/8 regarding our timing being retarded question. Does it mean anything to you that:

A) Timing was way off when he looked at it the first time with the light?

B) Shortly after he did the jumper wire thing was when we had those 4 nearly normal starts (that we assumed were due to unplugging the AFR controller)?

I remember a few people saying we could have a sticking valve. I know our motor is the non interference kind, and my understanding is that means the ECU sets the timing, regardless of TDC when new engine was first started, right? And I know the crankshaft and cam sensors play some part in all the timing stuff, which have both been replaced. And somewhere in that whole picture the knock sensor comes into play, right? Confused. Tried reading FSM about it, but still confused. Anybody care to give me a run down on all this timing stuff and how it might be relevant to our situation? Could a problem with the ignition timing or a problem with the timing belt cause the hot start issue somehow?

 

It's funny how things have changed. Until now, not getting an update from the mechanics drove me nuts, with the waiting and wondering.

And now? Now I am glad to not have received an update yet. Because that tells me the mechanic is thinking and testing and trying to diagnose accurately rather than guessing and throwing parts at it. Especially when I know for sure that they are looking at it, and it's not just parked on the "pain in the ass mystery problem back burner" like it seemed the engine mechanics were doing. These guys are close to home, so on my way to the park yesterday, I saw the hood up and the mechanic looking at it. I'm grateful that he's even finding time to take a look so soon after we brought it in, because I know the guy is swamped with other cars and I'm pretty sure a fair amount of those came in before the Taco.

As excruciating as the waiting game is, I would so much rather get no news than get inaccurate news, after all the countless false hopes and their associated highs and lows. Almost not even a challenge for me at this point to NOT call there asking for an update. And you guys know how much I struggled with that in the past!

But as always, TW will be the first to know once I hear something (well, OK, 2nd to know after my husband - sorry guys!)

Emailed the last mechanic yesterday - you know, the one that said replace fuel pump. Told him I hoped he understood why we wanted to get another opinion before replacing it again, and thanked him for looking at it and trying to help us. And told him if this mechanic told us to replace the fuel pump too, I'd be sure to let him know because karma can bite so I'm not going to keep it to myself if I'm wrong

 

Ever since all the Taco nightmares started, I've been worrying more about how the Civic has been leaking oil for some time. Until the Taco problems, the plan was just let keep dumping oil in and let Civic die of natural causes then replace her. We've basically looked forward to the day that we'd be forced to replace her, because of all of her cosmetic flaws and age and tiny size (I bought that car in my early 20's - all that mattered to me then was having a sunroof and a stereo and something small enough to easily maneuver!). But now, things have changed and we need that little cosmetic nightmare of a beast to keep going, at least for a while.

Husband suspected Civic needs a new valve cover gasket and new spark plug tube seals for the oil leak. He replaced the gasket and tube seals himself a few years back with some crap aftermarket cheapo set. I called Honda this morning, and they were SO NICE and HELPFUL!!! Parts guy looked up all the stuff and it was DIRT CHEAP compared to what we've been dealing with on the Taco. Talked to service and explained husband's description of where leak appears to be coming from, and he listened closely then explained in detail why he thought we should also replace the valve cover washers - which are also dirt cheap. Parts mentioned their techs always say what a PITA replacing those washers are. I asked him if he thought my husband could wind up doing more harm than good if he tried to do that himself. He laughed and said he couldn't answer that. Kind of joking, I asked how much for labor to have them do it all - then braced myself for a heart attack. He said $55. And $45 for all parts. Would have kissed him through the phone if I could have. Civic has an appt on 3/7 to get her oil leak fixed, hurray! While getting us in the computer, he asked the Civic's color - told him red, as far as what paint is left. Told them the nightmare we've been dealing with on the Taco, and how Civic is a cosmetic nightmare that I'm kind of embarrassed to bring in there - service guy laughed and said, HEY, she still runs though right?!? Love those guys. Definitely made the cookie list. And let them know how totally completely impressed I was with how helpful and nice they were, particularly after some of the service (or lack of I should say) we've received the last few months on our Taco issues.

Bama, me thinks those Honda guys are the kind of folks you always refer to when you speak highly of mechanics/techs - it was such a pleasant experience for me to deal with some people like that!

Bet that's how all my TW buddies would be/are like as mechanics!

 

CLASS IS NOW IN SESSION!!

OK. This will be in simple terms, so that it will be easiest to understand.
Crankshaft sensor - sends engine speed, and cylinder position to the ECU
Camshaft sensor - sends a signal once per camshaft revolution to the ECU so that the ECU can confirm correct fuel timing (When do I fire the injectors)
Knock sensor - sends a signal to the ECU if there is a significant "noise" in the engine, indicative of "ignition ping"
ECU uses crankshaft signal to determine when to fire the ignition coils. Adjust the time based on the knock sensor input.


So how does the ECU adjust timing, and why is it important to get the ECU into a base-time mode?

In order to verify base timing, you need to use a timing light. (Looks like a futuristic gun, connects to the #1 cylinder coil, and the battery. Will flash a strobe from the tip of the "gun" every time the coil for cyl #1 fires)
Once you have the timing light hooked up, you have to disable timing advance. There are a couple of ways to do this, the simplest being shorting the correct diagnostic wires. On the 3.4 engine it would be this way:




This tells the computer to NOT advance or retard timing. Once that is done you can verify the correct BASE timing, which should be 8º-12º before TDC.

Why is this important? Well the ECU directly controls ignition timing. When the engine is at higher RPMs, and under load, advancing the timing (making the coil fire a few miliseconds early) increases power. However at idle, advancing the timing too much will cause hesitation, and stumbling, as well as excessive heat, and will eventually reach the point where it would fire too early (engine ping). So the ECU needs to be able to adjust this timing up and down all the time.

How does the ECU get the most power and best economy? Well, when you first start the engine the computer will get timing to the base number, and then advance it until the knock sensor detects an ignition ping. (You won't even hear it, but the knock sensor will pick it up) Once it detects that ping it will back the timing down to the normal timing for idle. It does this in the first couple of seconds of the engine running, and this is the first diagnostic test of the knock sensor. Then when you are driving, and you accelerate, wanting more power, it does the same thing. It will advance the timing until the knock sensor detects a ping, then backs the timing down just enough to stop the ping.

So why do so many Tacoma owners talk about having spark knock all the time, and Toyota having a bulletin to fix it? The software was not sensitive enough to the knock sensor's signal, and would still allow some ping when it backed the timing down a little.

 

Thanks for the info Bama! Good reading for sure, really appreciate it! Just shared w/husband too!

By any chance do you know where we might find that bulletin you mentioned? Curious if it could have anything to do with our situation, and just interested regardless.

 

https://www.youtube.com/watch?v=GYuYtgzqLjo

One of Waylon's best, enjoy!

I wonder if this song was playing on Taco's stereo during our last visit there (engine mech) while they were messing with her....

 

I honestly don't remember, but if you search this forum for engine ping, there are many threads that discuss it.

 

Why havnt you tried the donor ecm you have?
I would have tried that before taking it to a mechanic.
I wouldnt let mileage scare me away from a used wiring harness either.
if I had to guess I would say that they left something plugged in when they went to remove the motor and it was pulled on pretty hard before someone noticed it...

 

Jen has lost her mind. Just like her truck.

 

Pretty sure we'd have to pay to have the donor "flashed" before putting it in, and also I would not be comfortable swapping a part like that ourselves, so either way we'd have had to go to a mechanic. So may as well let them have a shot at looking it over before going straight to insisting that they switch that, in case the ECU is not the issue.

The mechanic called yesterday - I really like him a lot. VERY honest and humble, which is so important - makes it easy to immediately trust him, like it was with the angel mechanic. That has been one of the worst parts of this - dealing with the handful of overly arrogant mechanics who've looked at the truck - the ones who oversimplified the problem because that was easier than admitting they didn't know how to fix it - and I'm not just talking about the engine guys. So it's a huge relief to be back in the care of someone who is totally the opposite of that. He's got a few leads in mind, things he's looking at today. But communicating with him was good, I like the way he reasons through the problem and uses a very logical approach - and I can tell he's got that fiery determination like the angel did, which is exactly what we need. Honest and determined and good at communicating.

Told him I was worried it could be a wiring thing, then said how since it IS a 17 year old harness, surely it's brittle and if those guys were as careless handling that as they were with so many other things, it would make sense to think of that being the culprit. He said he wouldn't question our harness - said, this is not a car from the mid 80's or even mid 90's, plus Toyota makes good quality parts, so sure, it's possible that it's a wiring problem, but if it is, he wouldn't even think twice about it being due to the harness being old/fragile/brittle, he'd think it was due to SOMEONE leaving something connected by mistake.

We talked a fair amount about what's been done already, the AFR gauge, all of the timing stuff we've noticed, the TPS stuff, possible TB/IAC issues, wiring concerns, why he thinks it's not a fuel pressure issue, etc. Honestly at this point I think he's just trying to figure it out before really saying what he thinks it might be, and I'm actually glad for that, because I am so over the ups and downs - just cannot take 'em anymore.

I encouraged him to take his time, we'll be patient, we want this to be the last stop and we want it fixed right, and we are trusting in whatever order he sees fit to do things in, etc, because our neighbor said what a genius he was. He laughed and said, "No, I'm just a determined SOB!" And that's exactly what we need!

I told him know one way or another, this WILL be the last stop - either he's fixing it, or he's buying a Tacoma.

 

for now she has to wait on a report from her electrical guy so im sure if there are questions about the wiring he will fix them for her

 

Dude, you got some killer smart ass humor! Love it!

I am surprisingly doing much better than I have been in a while. I don't know, I just have this feeling that this guy is gonna get it..........and he's super nice and easy to talk to about it, so that takes A LOT of the stress out of it for me, since I'm the primary mechanic communicator from the start, while husband is at work.

Happy Friday, haven't lost it, at least not yet!

 

Hey, First Gen, Jen.

If you haven't lost it by now, you ain't gonna lose it! You are the Energizer Bunny of dedication when trying to find out these issues. You just keep digging and digging and digging looking for solutions. I got faith that you and the hubby will find the problem.

As always, in to the finish.

KO

 

Umm. Was it ever determined where the base timing was set at?. 8°-12° is the range as per.

I'm almost positive it was and has been checked, by many. Can't remember the degree's mentioned.

 

After all this, why hasn't the AFR been permanently/completely removed for criminey sakes, not needed, get rid of it, then move on...my general rule for electrical aftermarket addons, especially electrical, remove them until the problem is solved, then go back if you so desire...

 

Thanks K!

It's funny that you described it as digging - last night we stopped by the shop that has it and we were talking to the owner about the whole thing, and she said the mechanic that's working on it "is like a dog looking for his bone, he just keeps digging and digging and digging"

I was like, PERFECT. That's what we need!!