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

Thanks Steve! It's started fine cold 95% of hte time since new engine was put in, save for a couple of times, one of which being Friday evening after it drove like shit that day (rough idle/lurching 2x). It sat 5 hours then started like total garbage that evening. But since then, it's started great cold every time.

Here's what SG II booklet says about that IGN value (IGN = Ignition Timing):

"Shows the amount of timing advance (or retard). The more advance there is (or less retard), the better for fuel economy and power. The limit is set by the octane of the fuel, the intake air temperature, and the load on the engine. A lower than normal amount of advance for similar temperature and speed could indicate too low an octane of fuel is being used."

There is clearly some kind of connection here guys, because we noticed (as posted yesterday) that the IGN value on SG was going up with each new coil pack. With all 3 old cp's, it would range from 5-8. With one new, it would range from 8-14. With 2 new, higher (forget exactly). This morning when we started it after all 3 were new, I saw it read 27 at one point. Some how changing those coil packs and seeing this number go up and seeing the timing be retarded on that number marker thingy next to the timing belt - somehow these things have GOT to all be related, don't you think?

I'm not freaked out, even if ECM is f'ed, we have a back up, so right now I am just dying to figure out how this shit is related and whether there's something simple we can do to finish the job.

Please give us yoru thoughts! Gonna fire her up and drive a block or two now I think....

PS: with the SG info above, I should mention for those that don't know this already, the one consistent factor we've noticed with hard starts is that IAT (intake air temperature sensor reading) HAS to be ~70+ for a hard start to occur, and the higher that number is, the longer the crank time.

Also regarding the SG info above, I should mention we've used only premium fuel since new engine....91 I think it is? Not 87 like we used to....

 

Drove about 5-10 miles just now, seems to be running good. Gonna switch drivers now (my turn!) and see how it does.....hoping maybe it does it's weird ECM magic and realizes, HEY! THEY GAVE ME 3 NEW COIL PACKS AND WIRES, SWEET! I FEEL BETTER NOW!

 

I think the timing belt is ok.

 

resetting the ecu it so very EZ, just disconnect the neg, wait a few minutes to make sure it discharges completely, reconnect...takes maybe a 100 miles , give or take, for it to relearn shiza...and it ain't gonna hurt anything to reset this way...

 

well weak coils will definitely cause weak/hard start issues and add just the right engine temps so the engine is tighter then when cold so it adds more drag and that could be it.

 

jen, we have all felt your truck was retarded for a long time now but it had nothing to do with the timing


ps - get on the ball girl post #2000 belongs to you dammit! so be ready this time

as I said

so im not saying you aren't right about a temp difference if it isn't orientated as directed, only that the jiggle hole isn't the root cause, its something else because the jiggle hole only has one function, to bleed air when the dry air filled system is being refilled with coolant.

 

OK, drove another ~6 miles, so a total of ~12 miles just now. No lurching. Maybe just a teeny bit of that shudder/rough idle feeling, although honestly I think maybe it was normal stuff - certainly not even in the ballpark of what I noticed Friday - that for sure was some seriously abnormal shuddering/rough idle stuff.

We noticed the ECT was down around 190-195 consistently while driving, whereas before changing the thermostat and redoing coolant it was consistently 200-205, so that seems like a positive change.

Gonna start her again at the 30 min mark, which will be 5:42 Pacific Time - stay tuned for an update on that, should be just shy of 6pm pacific.

Honestly, we would like to avoid disconnecting the battery - not 100% opposed if we really get to where we think it's worthwhile, but hoping to avoid so that we don't mess with our mechanic's resetting the ECM. Just talked to neighbor who hooked us up with that mechanic, and he thinks he did something fancy to "reset" our ECM - not just disconnecting battery. So on the chance that the poor guy actually removed glovebox, disabled air bag, and physically got his hands on that ECM to do something to it, I would feel like a real ass screwing that up. And it does seem *possible* maybe (hell, I don't know!) that just simply driving it and letting it realize, hey these coil packs are new and they feel great! could be enough if they are actually the fix, without disconnecting the battery.

Steve, I hope you are right. We talked about it more (the timing belt), and agreed, jeeze, if those guys knew enough to set the jiggle valve the right way, could they really have tarded out that bad on correctly setting the timing belt?!?? Hope not, and doubt it. And I'm pretty sure we've decided that we're not messing with it even if we do keep seeing evidence of it being wrong, just cuz I'm thinking that's a job better left to our new mechanic or a dealer if it comes to that.

I think when we restart it at 5:42, husband will look at timing again with that light thingy and see if any different than earlier.

Thanks for reading guys!

 

You don't have to undo the battery; the truck will re-learn as you drive.

 

I gotta go to bed. I'm not gonna see the fallow up until tomorrow. Dammit!

 

"like"

 

K, how could you miss the excitement like that??!! What if this is it????? You never know, it might be it and not just the 87,000th false alarm!!!!!

Have a good one, see ya tomorrow!

 

Steve, any idea how many miles for it to relearn something like "hey, I got new coil packs!"?????

I know our mechanic wanted us to try to do a "complete drive cycle" and I have no clue what that is. Was gonna google it, maybe I'll do that now. Anyway, I asked him if that was like 200-300 miles or so, and he said "at least". But that's for him to hopefully get the ECM to set a code, and with that weird 2 trip logic thingy, where the truck won't set a code til a problem occurs a couple times or more, anyway....that all seems different than just trying to get it to realize it has new coil packs.

Its still weird as hell that no codes so far, even with all the weird stuff going on. Don't know, maybe a fried ECM and it needed the CPs?

 

OK, the good news is husband just rechecked the timing with the light and it's now falling within where it's supposed to! Seems like it fixed itself from driving 12 miles, wow! That seems positive no matter how ya slice it!

The bad news is excessive cranking on the start. Not the worst we've ever had, but def. not normal or even close.

The puzzling news/change is we noticed IAT (intake air temp) value on SG was 112 this time when we started it, which it's NEVER been that high. And ECT continues to stay down around 190-195 at full temp, so things are a-changing that's for sure. Not sure what it all means, but hopefully leading somewhere good....

Thinking we're gonna do a little more neighborhood driving now, since it seems something positive happened just from that last little spin.....will update again in a bit!

If any of this triggers any lightbulbs for anyone, share your thoughts/ideas/theories!

Thanks for reading guys!

 

well all I can say is so far everything you have done has made positive improvements on how it runs even if it hasn't solved that gremlin issue yet.

as to the ecm resetting it will reset things pretty quickly so maybe after 2 or 3 short trips of a couple of miles (like one trip to the dog park and back) im sure it has reset the settings

 

Just drove another ~20 miles, getting up to ~60mph for a good chunk of it, and it is driving beautifully again. ECT staying down around 190-195. Timing definitely fixed itself (I think I already mentioned that) but we are really happy about that because it seems our ECM can't be totally tarded if it's capable of adjusting the timing in conjunction with the knock sensor! Just rechecked the timing for a 2nd time, totally normal, hurray!

Yep, Keakar, may not have licked the starting issue yet, but definitely accomplished some positive changes with all of our stuff this weekend, AND got to cross some stuff off the possible culprit list - MAF checked out, and I know there was at least one or two other things that we know now that we didn't Friday night - so all that feels great!

Still hoping by some miracle that the coil pack/wire change will lick the starting issue, and that maybe it just needed to get driven enough to effect the change. Gonna start it again in 30 min, not holding my breath, but one can hope, right?

 

Jen, do you realize how much you've learned about the mechanicals of your/a truck?

You probably know more than a first year mechanic in the trade

 

SHESH! I go and take care of stuff for my brother and am gone a day and MAN crazy stuff. lol....

Clearing codes- erases any current, pending, or history codes in the memory. Also will reset all general self diagnostics test status to zero. (equal to "logging off" Windows on your PC, then logging back in)

Resetting the ECM - wipe out ALL memory, including codes, general diagnostic test status, as well as all learned information (IAC preset, etc)
(Equal to rebooting your computer)

flashing the ECM - wiping ALL DATA from the ECM and reinstalling the operating program (Typically can only be done by a dealer, or a business that specializes in this
(Equal to erasing the hard drive and reinstalling Windows all over again)

Surprisingly on the Tacoma 3.4 engine I have found this to NOT be the case. Don't ask me to explain HOW or WHY, but if you install the jiggle valve in the 6-oclock position, the engine will typically run about 5 degrees warmer than if you install it at the 12 oclock position. I have no rhyme or reasoning behind this, but have actually tested this theory on multiple 3.4 Tacoma engines in my shop. It really is true. (That being said, a small difference of 5 degrees in engine temp really won't make a hill of beans difference)

Since the computer is what controls the ignition timing, it can alter the advance by all sorts of amounts based on engine temp, rpm, engine load, if the AC is on, if your blower is on high or low....you get the idea. The only way is to use the jumper wire method which tells the ECU to NOT alter ignition timing, so that it can be checked. HOWEVER the timing belt has NOTHING AT ALL to do with IGNITION timing. It only affects valve timing. All timing is base-lined from the crankshaft position sensor.

This is a public service announcement....

 

Thanks for making this post. Everything I was not articulate enough to conveigh is in your comments. Good, concise info.

Thanks

Kirk

 

Aww, thank you!! At least there's this bright shining positive light in this long sucky journey!! Not so sure I deserve quite that much credit, but hey man, I'll take it anyway!! Thanks!

Had another one of those moments like the R & R moment with husband and parts store guy on Saturday when we picked up all those goodies - parts guy was explaining something to us, and I knew exactly what he was talking about (can't even remember right now what it was - just woke up, not enough coffee yet!), then husband was questioning what he'd said when we left. I was like, "no, he's right, because so and so on the forum was just explaining that the other day, so don't worry, it's true, that's how it works."

Point being, where ever I am in ranking on my mechanic education, once again the vast majority of the credit goes to ...............

TACOMA WORLD!!!

 

Received a bit of information on what I was wanting to check out for you Jen. A fellow tech who is a Toyota Tech had the following to say: