Bad engine

I was told my 4.0 engine was shot after a few other small problems I took it into the shop. They told me it had a bad miss after they had had it about a week trying to figure it out they sent me these photos.

 

That's the cylinder bores?
What happened?

 

Idk , they say it looks like it got water and sand in it but I haven't been in deep enough water where it would have sucked it into the engine.

 

Define "deep enough." How deep water has it been in, and for how long? How many times?

How many miles are on the truck?

 

Smells like a sabotage/vandalism situation.

 

I want to say that there's no way those pics are the bore, but I'll say I highly doubt it, looks to me like valve stem pics.

 

I thought that myself when I first saw them, but I think that's just an accident of the partial lighting from the mirror angle. In many of the shots you can still see the flat, rusty face of the piston head below the mirror.

The problem here is that the photos are taken using a mirror on the end of a borescope or probe, rather than a dedicated side-pointing camera as is now common on the several inexpensive, very high-quality fiber optic gooseneck camera scopes that are available online these days. (A mazon, etc.)

 

If and I say if those are bore pics there's no rings left on the piston.

But that's just my opinion.

 

As for how long it has been under water just typical creek crossings up to the wheel wells never just sitting in water as long as I've had it. 217,000 miles I'm the 2nd owner. This whole thing started when I took the MAFS out and cleaned it. When I put it back it went into limp mode. I thought it was just the CPU trying to re-learn the MAF being cleaned. Then they told me the switching diverter valve was bad and that was causing the problem. Ok installed that. They say it still has a bad miss and they can't figure it out. They pull my plugs say they look bad. They tell me part of the miss is my #4 isn't firing. Today they tell me I need a whole new engine!!

 

I would get a 2nd opinion.

 

OK we know the root of the problem; buy a new MAF senser which started the problems, then find a new mechanic cause they have no clue and just want to empty your wallet!

 

Did they tell you what exactly you're supposed to be looking at?

 

Has a new maf sensor been tried?

 

Weirdest bore shots I have ever seen in my life. I can see the curve of the piston but not the curve of the cylinder walls. Sure looks like water slurrry was introduced to the cylinders because I can't see that running well enough to get out of it's own smoke screen.

 

Did you ask what exactly the pics are? IF those are your cylinder bores,that thing would've looked like an old steam train smoking. Something ain't right here.

 

Put a new MAF sensor in and see what it does,the whole you need a new engine thing is mind boggling.
And those pictures are crap,who knows those pictures are of.

 

I'd get a 2nd opinion or better yet buy a cheap inspection camera yourself. Those pics could be from a 64 impala sitting in a junk yard. I wouldn't base a motor replacement on those pics and I'd def want some other verification. If that's sand and water intrusion there will be some other indicators beside just the bore pics. I'd at the very least expect the oil to also be reflecting that condition.

 

At $110 for a DEPSTECH DS580 flex-neck camera on Amazon, OP could do 50x better than the photos provided by the mechanic. Here's video of the inside of the cylinders on my 4.0 that I took myself:

(Quoted from: https://www.tacomaworld.com/threads/cylinder-1-2-misfire-help-please.792893/page-2#post-28406650 )

BTW if you want to see the full set (all 6 cylinders) of my 1GR-FR 4.0L V6 cylinder inspection videos, as a baseline for comparison with your truck, you can do so here:

https://www.youtube.com/@JohnDoe-cw3yl

These were taken on the same day, as a baseline for normal operating condition. About 68K miles on the engine + vehicle. No codes or other obvious problems with the engine, exhaust, or cooling system. Normal acceleration under load, fuel consumption (MPG) normal. Doesn't burn any oil between changes (3-4K OCI,) doesn't lose a drop of coolant over years. Engine + drivetrain + exhaust sounds normal across full RPM band.

 

Don't want to side track this thread, but what inspired you to do a cylinder bore check on your truck at 68k which was exhibiting no problems?

 

As a DIY'er with no other prior experience I just wanted to establish a baseline for what a "normal" engine looks like. Also could be useful if I'm lucky enough to keep the truck to 125K, 175K, 250K...350K and beyond. Plan to repeat it every 50K miles or whenever I replace the spark plugs, which at the rate I drive these days might only be once a decade.

Also would come in handy if I wanted to sell the truck to someone, although I didn't do a good job proving the shots properly. (I.e. I should've started each shot with the ignition on, showing the odometer, then loaded a live web page of a major newspaper to prove the date, then walked back to the engine and plunged down each bore.)