Uh oh.......is my head gasket failing?

Brought a 97 tacoma up to the north from Miami a month ago and it's springing leaks left and right. First what appeared to be the oil pan gasket, then the LSPV valve. I planned on just adding fluid until I could afford to get it fixed, but while regularly checking the dip stick I noticed that the oil leaked down to the half way point, then just stopped. Which I thought was odd, because the leak didn't stop.

Last time I checked my oil level I had to look really close because it was dark, and I could smell gas on the stick. Popped the oil cap off and smelled the back of it, and it also smelled like gas. Pretty strong. Now, it's a stick shift, and I've stalled it trying to get started on some steep hills a few times, so I was hoping maybe I just flooded it once or twice trying to start it too soon after stalling out (wouldn't start, had to wait a few seconds before it would).

Got to thinking that I might have a head gasket issue, so I looked around some more. No 'milkshake' froth that I could see in the oil, but the exhaust had a certain 'pleasant' smell to it that seemed a little different than other exhaust.

Just checked my coolant and found it was short about a quart or a half quart (after being flushed just a month ago), and there is some kind of oil/gas residue floating on the surface.

I found a mechanic who offered me a deal as long as I get all the parts together myself. Does this sound more like fuel injectors, or head gasket? Or both maybe?

 

If fuel were in the oil I'd say head gasket. Does the exhaust smell like burning oil? Or maybe like a bit of coolant? I'd get that fixed asap to avoid burning her up.

 

if you smell gas in the oil then your injectors are leaking and its seeping passed the rings when shut down. one or more of your injectors is dripping gas after the engine is shut off. this also loses fuel pressure and can cause longer then normal cranking to start the truck because it must rebuild fuel line pressure.

what you describe is not signs of a bad head gasket, other then the typical loss of compression, a bad head gasket causes either water in the oil or water disappearing from radiator but not leaking out anywhere

 

Tomorrow I'm driving straight to the nearest oil change place to get it flushed, and from there to the first mechanic I can find that can diagnose it.

 

I have water disappearing from radiator without appearing to leak out anywhere, also looks like there's an oily film riding the surface of it.

Maybe I got real lucky and it's a leaking injector paired with a bad head gasket...?

 

ohh, yep I think there is a likelihood you have a double whammy going on

the fuel in oil is injectors but water in oil or oil in water or both is usually a bad head gasket

do you have an auto tranny? double check your tranny fluid to be sure it isn't a bad radiator tranny cooler leaking

 

Nope, it's a standard tranny (with a clutch on the way out the door, bearing first). I think the vehicle just completely freaked out going from Miami heat its entire life to northern winter. That part didn't even cross my mind when I bought it, I was all starry eyed at the complete lack of rust. Kicking myself now.

Oh well, I found a young upstart mechanic who offered to do anything it needs for a grand + parts. If it turned out to be the injectors were bad, what kind of parts would I be after for those? Is it usually the seals around them, the whole unit, or do you really have to get in there to find out?

Another stupidly optimistic thought-- Is there any way I can get fuel in the oil by stalling, and trying to start it back up too fast? Compared to a lawnmower, it felt like I kind of flooded the engine there for a second- wouldn't start up right away, though I tried a couple times before I learned to wait. Had to give it a few seconds. Happened a few times.

 

ohh wait, southern truck brought up north? I would suspect your coolant didn't have any or the wrong amount of antifreeze and maybe the winter ice did something to it.

hopefully its just a gasket and no engine damage has occurred.

nope, when the engine is not running the injectors are closed and no fuel gets into the cylinders but if an injector is leaking it drips or even dribbles gas until all the fuel pressure is gone so you can have a good bit of fuel leaking into each cylinder that has a leaking injector after shutdown.

often injectors are sent out to be "reconditioned" at "specialty" shops and its not cheap but neither are injectors.

you never filled in your truck info in your account profile so we don't know what engine you have but v6 injectors can cost around $200 each where the injectors for my 2.4L engine I got a full set of replacement upgraded 4 hole injectors for only $110 (4 hole injectors are used on the newer trucks)

 

A compression test will show you if there is a leak inside the engine. A leakdown test will show you where. You'll need an air compressor though.
A coolant test will show you if there is exhaust in your coolant. That's a sure sign of a gasket leak.

If a(all) spark plug looks like it was steam cleaned, it's burning coolant=coolant leak.

+1 on the injectors being a likely cause, but check to see that the engine reaches operating temp, to rule that out. Short trips, or a stuck-open thermostat can cause unburned gas to stay in the oil.

 

This is why this forum is great. Seems I was half right. Thanks for chiming in and teaching me something new.

OP, you have some good info to start with. Good luck!

 

Sorry, it's the 3.4 V6 engine. Before I left Florida I checked all the fluids to make sure everything was OK, and it looked like there was nothing but water in the tank (it looked completely clear, but the guy I brought it from said he flushed it himself at a 50/50 ratio of coolant to water). Had a local shop do a coolant flush and oil change with the fact that I was bringing it into freezing temperatures in mind. When I got it back from the Miami tire place it was the neon green I was more used to.

I just had the oil replaced in the truck today, though the guys there couldn't help (or didn't want to) with any diagnostics. I'm going to start calling around tomorrow morning to find a shop that can run the tests skytower suggested. Preparing for the worst, I've already ordered a top end gasket and timing belt kit (any of the O-rings on the injectors a potential culprit?). Best case scenario, I send them back. I had a closer look at the coolant and there's definitely black crud in the tank, both at the bottom and running up the sides, but the film on the top doesn't seem to 'shine' as much as I thought it did initially (flashlight vs sunlight), seeming more 'dirty' than oily. But what else could it be?

 

the injector o-rings and seals are just there to keep gas from leaking outside the engine. the injectors themselves have and internal valve seat that is going to be what is leaking and sometimes its just dirty and cleaning solves the problem but in my experience that is rare to fix it and most times the only fix for that is to replace the leaking injector.

as to what the film could be, who knows, i have seen guys run straight water in the radiator then when it gets corroded they spray wd40 in it or squirt oil to make it look better then clean it up and fill with antifreeze so maybe what you say was that or a spry used for something else that got into the radiator or coolant hose connection somewhere.

i would not expect the worst unless you actually saw a drop of oil floating in the radiator. the oil runs more pressure then the radiator so most times a bad gasket will allow oil into the water and not the other way around but it can happened when the engine is turned off and there is no oil pressure so since you say no sign of milky oil there is hope that that film was just something that got into the radiator somehow and i wouldn't be sure just yet its a definite sign of a bad head gasket merely because you saw what appears to be an oil film in the radiator because if the engine is overheating it can lose water through the overflow and you wouldn't notice it. now if you have gas mixed in with the oil its not getting proper lubrication and that causes engines to overheat so the scenarios are all over the place but they can all be pointing to just leaking injectors causing engine to overheat and lose water. so im just saying, dont assume anything is bad beyond the injectors just yet.

 

Just took it in for the tests. Came back negative for emissions in the coolant, so it looks like my head gasket fears there were unfounded. I'm guessing that dirty looking stuff in the coolant is something leftover from the old coolant, or maybe some stop-leak residue of some kind.

*HUGE SIGH OF RELIEF*

He couldn't help me on the gas-in-oil problem, though since the truck doesn't have any trouble starting I'm going to start looking elsewhere for the source of that. Interestingly, my power windows, temp gauge, tach, and lord knows what else (hard to check dash lights by day) all died the second I put it into reverse to drive to the mechanic. He said the fuses all check out and that it's probably a relay. I heard that the backup light switch might be tied to those areas, and the one that's in there now hasn't worked for a while (it leaks oil out of the connector plug, not around the seal). I have a new one but I haven't been in too much of a hurry to put it in. I wonder if that switch shorting could cause the rest of the failures.

EDIT: The 10 amp gauge fuse was blown, I guess the mechanic never checked the under-dash fuse box. Put a new one in and it blew again as soon as I put it into reverse. Replaced the backup light switch on the tranny and that solved the problem.

My guess for the gas-in-oil is that the engine is running too rich. What controls that? The thermostat?

 

have your injectors removed and sent to be tested and cleaned.

there is only one reason for gas in the oil and that is one or more of your injectors is leaking

gas in oil strips it of its lubricating properties and can seize up your engine, its not something to ignore.

ps - the ECM controls the fuel air mix by reading the MAF sensor and o2 sensors to adjust the right mixture but it would need to be flooding to get gas into the oil and that can only be if gas is literally dripping from a closed injector, which produces a "flooded like" condition

 

Tracking that down is first on my list. The dipstick smells like gas but it won't burn if you put a lighter to it. The mechanic I took it to suggested that the thermostat might be defaulted causing my engine to run like it has a choke wide open, which could cause gas to get in there. I'm not sure if that's an easier thing to check on than pulling the injectors, but I'd like to cross it off my list at least. Maybe I am just going crazy in the nose, but I swear I can smell gas on it-- then again I did put fresh stuff in it yesterday.

 

there is no choke on EFI engines, gas flows only when the injector is told to open and it is supposed to close and shut off fuel flow otherwise.

if you have basic mechanic skills pull the injectors out yourself and bring it to an injector shop to have them checked

if you are feeling more ambitious you can try testing and cleaning them yourself by watching youtube videos on how to do that like this guy https://www.youtube.com/watch?v=dp-ECEpN52k

 

Does your temp gage reach normal operating temp? Double check it with a non-contact IR thermometer. $30ish at home depot, or borrow one. If it does, your thermostat is working fine. 185-195 degrees, or so is normal. It depends on what thermostat is installed.

Please quit telling him to do the time consuming/expensive things first. Troubleshooting is more than just easter egging your way through the truck, replacing parts you suspect are bad. It starts by confirming that the easy/cheap causes are ruled out first. (Rant over)

 

you mean like you telling him to not fix the gas mixed in the oil issue first, lmao

gas in the oil can ONLY be there from leaking injectors and pulling a set of injectors is not much different then pulling a set of spark plugs

while you are singularly fixated on the water leak issue which is only a minor hazard to the engine from overheating, and the radiator being a quart low on water is fairly common and can easily be explained by an air pocket left behind from the recent radiator flush he had done to it. you cant just ignore the immediate danger in the possibly engine destroying "gas mixed in the oil problem" and a water leak fix couldn't ever be the cause of that.

the second most common issue with the 3.4 v6 engines after the timing belt is clogged or leaking injectors and even for just a routine maint item to do on a high mileage engine, they should be pulled and checked after that many miles, for you not to know that says a lot.

please stop suggesting people ignore problems that can destroy their engine

 

lets cover a few details on the priority here which is the gas smell in the oil issue.

did the oil smell like gas before you left florida? and did you notice the gas smell right away after reaching your destination?

did you notice if there was there more oil in it (marking higher on dipstick) after reaching your destination then what you had before you left florida?

with fuel leaking into the oil, if its a big leak then the oil level will rise over time, if the oil level isn't rising then its a very slow gas leak and not as dangerous to the engine. mosrt likely just a slow drip from one of the injectors doing it.

was this your very first oil change since you got the truck?

if you never changed oil before, then maybe the PO put something into the oil in preparation for you to buy the truck, like some type of an engine additive that may have caused that gas smell you detected

 

I had the oil changed right before I left florida, I didn't even bother looking at the dipstick until I got back. I developed an oil pan gasket leak soon after bringing it across the freezing temperatures line. Leaks like a sieve for a minute or so when the vehicle is started cold, then stops as the engine warms up. Because of this, I can't really gauge whether or not my oil level is going up from the gas.

Naturally I kept an eye on the stick after noticing the leak, and didn't notice any gas smell until a few nights ago when I posted the thread. It was by chance that I had it close to my face. Didn't notice it before that.

Following morning I got the oil changed, drove it around for a day, checked it again and the smell was pretty much identical to what it was before. So two oil changes about a month apart.

The smell isn't super potent, like compared to smelling straight gasoline. But there's something going on there. Back of the cap had some old black oil on it that smelled like too, even after the most recent change.

One thing I've done since I bought the truck is let it idle warm-up for 5-15 minutes anytime I've driven it. I assumed it was good for the truck to let it warm up a while, but I've read that letting it warm up in idle takes longer than warming it while driving, and makes it run rich. I usually don't drive very far either afterwards.

Both first gen tacomas I've had have been really loud when you start them up cold, mostly in the fan area. This truck in particular sounds like it's pushing 1500 RPMs at startup, slowly inching back to a quieter idle.

The temp gauge gets to 50% and sits there like it aught to. PO replaced entire coolant system right before selling it. So far I've taken it to two mechanics and both have just kind of shrugged at me with nothing really helpful to say (my town has only one good mechanic and he is booked solid all week, everywhere else is pure amateur hour).

I guess I could take a stab at pulling off that manifold, though I've never disconnected a fuel rail before and it kind of intimidates me. I might try just making an appointment to get my injectors pulled and checked specifically, since telling mechanics what is going on and asking them to 'take a look at it' is getting me nowhere. There's no other symptoms that point to the injectors though. It always starts right up, never stutters, and doesn't throw any codes (or at least any that trip the check engine light). Though I know at least one of the injectors was replaced a couple years ago, along with the plugs and plug wires.