Need help, 2017 SR5 V6 troubleshoot

I have a friend who's truck was sitting garaged for over nine months. Tank was left with about 45% fuel. Oil was full. Battery had lost it's charge over that time, but I recharged it to full seven days ago and has been connected to battery charger which auto-detects fully charged status then switches to maintenance trickle charge.

Between yesterday and today I could not get the engine to start. The starter would crank and turn the serpentine belt but the engine just wouldn't turn over. "Check Charging System", CEL, and "!" are lit. Connected my OBD2 and no codes shown.

Is it possible the fuel pump died for not being used in those nine months? I noticed rodent tracks in engine bay; is it also possible they may have chewed on some hidden wiring which is preventing engine from turning over? Also, after the failing ignition/starter attempts, there is a buzzing sound originating somewhere in the center of the engine bay below the intake manifold/spark plug locations but I can't pinpoint the source of the sound...that buzzing sound goes away after turning the truck off...

I am perplexed by this mystery... What other ideas can any of you come up with which may help with this troubleshoot?

 

Is there fresh gas in the tank? Could it be stale fuel?

 

I've brought back bad gas with this stuff. Works really well.

https://www.archoil.com/products/ar6200-fuel-treatment

 

I presume it is nine month old gas. I didn't think of suspecting gas would be able to lose it's combustibility if kept in the tank. Evaporate if the cap was left open perhaps, but not lose flammability. I could be wrong and you may have a valid suspicion on that...

 

I think some high ethanol fuels can spoil faster.

Another relatively common possibility: look for rodent damage on the wiring harnesses.

Remote possibility: An animal has built its nest in the air box, restricting combustion air.

 

Wiring being chewed by fuzzy creatures is almost 100% guaranteed

 

I've left ethanol fuels here for 2 years in a snowmobile and jerry jug...it was still good enough to run without any issues. Lot depends on a fuel's freshness how and where it was stored. I would think if you pumped fairly fresh gas to start with 9 months shouldn't be a problem. Generally you can smell bad gas if the case. This sounds more like a bad battery, or a seized engine.

 

He said it turns over.

 

Spins over quickly? I would recommend reading battery voltage with a DVOM while cranking, if its at all suspect, say 10v or less, go get a new battery.

 

No, the op said the engine wouldn't turn over.

 

When you say the engine won’t turn over, are you saying it’s locked up? Since the serp belt is physical moving I have to assume you mean it won’t start. Please clarify.

 

My bet is on rodents chewing something up. My snowmobile, cobra and SXS routinely sit for 9 months and I've never had the gas go bad. I did have a fuel pump fail one time though over the winter. A few bangs on the gas tank got it unstuck.

I think he means it won't start when he says it won't turn over. If the belt is turning the engines not seized.

 

Maybe the gas has collected water out of the air (mixing with the ethanol in the gas) and it is on the bottom of the tank right where fuel is picked up.

 

Yeah, I started down that path when OP stated the engine doesn't turn over, that it was seized. But I think he means it doesn't fire, not that it really doesn't turn over.

 

Here's what I would do if this was given to me when I was working: Quick check for spark (during this I would get a feel if the engine spun normal or quick like loss of compression, or slow like low voltage), if spark I would suspect fuel , a quick spray of starting fluid or B12 Chemtool and see if it fires briefly on the spray. If it does I have either no fuel pressure, no injector pulse due to electronic issue, or stuck injectors. If I had no spark then I have a definite electronic issue. A quick check for a dead electronics is a code reader. If no communication then the fault lies in the electronics. As a retired Ford tech when I say electronics I refer to Ford's EEC systems. I don't know what Toyota calls their systems. It will be OBDII. My Son's 1990 Bronco sat for a long time and it was like this toyota. I was surprised when my quick checks verified 8 stuck injectors. I added a couple of bottles of Ford Premium Fuel Injection Cleaner to the tank. I kept it running by spraying about 6 cans of b12 into the air inlet. Eventually the engine heat and cleaner unstuck the injectors. Now I start his truck at least 1/2 times a month. My advice is from a lifetime of specializing in Drivability issues.

 

Its sounding more like a weak battery if it barely turns over. You need a fresh battery to produce a good ignition source alone, and who knows if there's even enough fuel pressure.

 

I appreciate all the ideas/replies everyone! Sorry if I had been using the incorrect terminology for trying to describe the various things...please correct me on it when I do!

I will try to address all the culprit suggestions you all mentioned...

Battery is good after I recharged x-days ago it and puts out the proper cranking amps to make the actual Starter kick in like normal and I see the Tachometer needle fluctuate at around 75-100rpm when I turn the key to engage the Starter to do it's cranking biz...but still the engine itself doesn't seem to get fuel to the piston chambers or there isn't any spark to ignite the fuel. I have tried that Starter Spray stuff to the intake and it still didn't make the engine start.

The ignition coil or distributor cap or spark plugs or spark plug wiring harness may really be the possibility to have been fucked up by the rodents. But my OBD2 did not show up any error codes at all even though the dash indicated the "Check Charging System", CEL, and "!" lights I mentioned previously.

I will also consider the sitting fuel in the tank may have in fact gone "stale".

 

...I don't know how to add your various independent quotes to make a better flowing Q&A reply....so...yeah...it's just all bunched up there^ hahaha...

I am just going to tell my buddy that I did what I can to the best of my ability and experience, and that he will have to hire a career auto-mechanic and not a handy-mech to help him figure out his truck.

Thanks again for the replies everyone!

 

I'd seriously suspect the battery. Just because you charged it doesn't mean it's good. Before giving up, I think it would be worth trying to jump start it if you don't have a way of confirming a bad battery. Good luck!

 

Get out of here with your logical and known to be useful troubleshooting steps for an engine that will crank but not start, this is TW!

"Check charging system" will usually be on anytime the ACC or Ignition is on without the alternator supplying power. It is telling you that there is a net drain on the battery because nothing is charging it. I think the ! symbol can be on for something as benign as the door, hood, sunroof, being opened with the key out/truck off. No codes being triggered could just mean that it did not have any last time diagnostics were performed or the ECU was sensing ranges on various things, which doesn't happen normally without the engine running. In other words, it may require a specific diagnostic mode or the engine to be running before it can check to see if there is anything wrong.

The engine has coil-on-plug ignition source, no distributor, wires, cap, etc.

I very much doubt 9 month old gas would be so bad that it wouldn't even burn. It's likely not getting spark or fuel not being injected. Do some basic combustion engine troubleshooting and you should at least find the path to go down if not fix the problem. Ethanol gas and low quality gas can build up varnish on parts that effectively clogs small orifices' and filters/screens. I wouldn't suspect that first, but it can happen. Fuel stabilizer will prevent that from happening when storing engines with fuel in the system.

If the battery can provide enough amps to crank over the engine/starter, it should have no problem powering the ECU, ignition, etc to start the engine.