00' 3rd gen: Shakes at idle, running out of solutions

[got_rwd?]

Hi guys, im a new proud owner of a pretty nice 4runner i just recently bought but now im hit with some problems previous owner didnt mention

Well its a 2000 4runner SR5 5speed 4x4 V6 Highlander/sport edition
151k on chassis , 48k on rebuilt motor
I LOVE IT but im having the following issues:

Startup , high idle around 1.2k to 1.5k rpms
drive and levels out to 750k rpm (still cold drives perfect)
Once at driving temp , she starts to "shake" or "wobble" . Idle stays at 750k
**No CEL**

Parts replaced to try and fix issue:
intake manifold gaskets (all 3)
new plugs and NGK recommended spark plugs
cleaned MAF
cleaned out TB and IACV valve
new TB gasket
replaced TPS sensor
clean injectors
new fuel filter
ran fuel injector cleaner
normal amount of slack in line
no vacuum leaks (sprayed carb cleaner to find leaks)

Another thing I noticed and is just worrying me:
Loosing coolant, nothing on the floor
doesnt over heat but i check and top coolant everyday (very small amount )
when I replaced the spark plugs, smoked white smoked on start for the whole day, doesn't anymore, probably burning off residue, not sure
** Heater doesnt work. Flushed core and its clean, checked valve and wires, not sure whats up**

My next option will be to do a compression test
I fear a headgasket failure but will that cause a shaky idle? The motor is fairly new (paperwork in hand)

Any input you guys might offer? I checked this forum for most of the above things ive changed or fixed, not im stuck. Im fixing my 04 6spd tl right now and swapping in a new clutch and flywheel ($750 repair) so this one will be put down for repairs asap.


Cliffs:
Truck shakes and wobbles at stop constant 750k idle no jumps in idle. Drives perfect above 750k rpm and highway
Changed a bunch of stuff out , problem still there
stuck like chuck

 

[brian2sun]

Sounds like a HG to me. Especially because you're losing coolant and if it isn't dripping on the ground, it's either burning off before it hits the ground or it's being burnt up in the combustion chamber via a HG leak or a cracked head (but you won't know which of those it is until you remove the heads). And yes, that'll cause a rough idle. Although on a side note, it is totally normal to run at ~14 or 1500 rpms for the 1st few minutes after a cold start up.

Besides that, it sounds like you've replaced/checked most of the other things it could be except the valves. But again, since you're loosing coolant, I would bet it's the HG or head(s). Mine ran with 2 cracked heads for a couple of years before it started missing consistently. It lost about a qt. of coolant every 1-2 weeks during that whole time.

 

[got_rwd?]

Sounds like a HG to me. Especially because you're losing coolant and if it isn't dripping on the ground, it's either burning off before it hits the ground or it's being burnt up in the combustion chamber via a HG leak or a cracked head (but you won't know which of those it is until you remove the heads). And yes, that'll cause a rough idle. Although on a side note, it is totally normal to run at ~14 or 1500 rpms for the 1st few minutes after a cold start up.

Besides that, it sounds like you've replaced/checked most of the other things it could be except the valves. But again, since you're loosing coolant, I would bet it's the HG or head(s). Mine ran with 2 cracked heads for a couple of years before it started missing consistently. It lost about a qt. of coolant every 1-2 weeks during that whole time.

yeah ive been dreading that . The truck runs amazing at any idle higher than that. Im just happy I can find a used motor or do head work for a good price. Even found a set of rebuilt heads on craiglist for $220! Very easy to work on.

I though maybe a burnt valve at first but it doesnt suck in air at the exhaust. I will pull the heads and have them resurfaced and rebuilt or just purchase the rebuilt heads

 

[brian2sun]

yeah ive been dreading that . The truck runs amazing at any idle higher than that. Im just happy I can find a used motor or do head work for a good price. Even found a set of rebuilt heads on craiglist for $220! Very easy to work on.

I though maybe a burnt valve at first but it doesnt suck in air at the exhaust. I will pull the heads and have them resurfaced and rebuilt or just purchase the rebuilt heads

Sooner or later you'll probably start getting miss codes too. Before you go pulling the heads off, do a compression test and a leak-down to confirm the coolant is going into the combustion chamber. Valves are a possible cause of the rough idle, but they don't explain the coolant loss like a HG/cracked head would.

If it's not a HG/head issue, it is possible that the valves need adjusting/fixing (rough idle) and the water pump and/or thermo is leaking just enough to dry up before it drips on the ground (coolant loss). That would also explain your issues so I would also look around the WP/thermo with a flashlight and an extendable mirror to see if there are any coolant trails.

Good luck and hope for the best!

 

[got_rwd?]

Thanks man! I just did a coolant flush with the prestone kit for a good 5 minutes. Did 50/50 coolant and water and going to monitor the coolant and watch for water trails from the thermo housing and water pump. Compression and leak down on friday.

 

[BrianSD_42]

This sucks, sorry to hear about your engine woes.

The rebuild was probably a crap job primarily to resell the vehicle. I assume you don't know what they did, what exact parts were replaced and with what. Did they resurface both heads ect.

 

[got_rwd?]

Here is all the work done:

Engine replaced with a "re manufactured" engine - 108k (carfax confirms)

Clutch and regular maintanence work done at 138k (carfax confirms)

Im puzzled, but ive read nothing but bad reviews about NECO as a engine re builder

 

[BrianSD_42]

So WHY can't you have it replaced by them under this warranty?
Demand they replace it; lawyer up.

That receipt is nice but it still doesn't answer any of the questions I mentioned.

1) What parts were used, doubtful Toyota, no-one can afford them
2) what was replaced and what was kept
3) were the heads resurfaced, both sides?

Ect.

Carfax is not very accurate and easy to "fake out" - I wouldn't trust them AT ALL.

..

 

[BrianSD_42]

Now I see that receipt is from 2004.

It is strange that since the rebuild, the previous owner only drove 48k miles in 7.3 years.

Since the engine blew at 100k miles is it safe to say it was a bad engine? I had major engine work done at 199k and Brian2Sun made it over 200k miles I think.

ASSUMING MAJOR WORK IS REQUIRED - If I were you I would consider either an engine swap or new vehicle, basically it doesn't seem like a good idea to rebuild an engine ($3000+) twice before it hits 150k miles, especially a Toyota V6 that typically makes it to 175k miles -nearly every time.

 

[brian2sun]

I agree with Brian, it was probably a crappy rebuild. BTW my engine finally gave up at 205K, but I believe the heads started cracking at ~185K.

Too bad, but since it's a 5 year/100K warranty, they probably aren't liable anymore.

 

[got_rwd?]

The original motor was replaced with a "re manufactured" engine by NECO so im guessing the original motor was given in as a core.

Im pointing toward a crappy rebuild of the replacement motor. I have receipts from 2005 on up for regular maintanence from the previous owner documenting miles and any work done. With that i was able to verify with the carfax to compare miles and dates. I have no clue why the original was replaced, I was told because the owners mother "offered" to do it and cover cost. Meh it thinks its BS.

I will check out the heads but if not, I already sourced a couple ready to drop in engines around town (im from Houston TX) for $600-$800 with 90k to 110k. LQK here just pulled in a 98 limited complete so i might pick some parts of there. No labor cost since I will be doing the work along with a couple uncles who own mechanic shops.

I bought the truck for $4800 and didnt expect any surprises at first initial inspection, receipts and carfax and 2hr drive back home. Lesson learned

I owned lots of long lasting toyota motors (2jz in 3 is300s and 1 gs300) 3sgte in my old boosted mr2 and 2 NA mr2s and along with a fx16 corolla and 95 corolla since I was 15 (22 now). This the first ive had issues with, unlike other people who have 3rd gens with 200k+ on the clock.

 

[BrianSD_42]

Sounds like a great plan to me. I wish I had those resources.

 

[got_rwd?]

Found my problem, took off my intake manifold to start tearing down the head, cant believe I didnt see this when I did the intake gaskets a few weeks ago.

Cylinder #4. I got a CEL a week ago for cylinder 4 misfire

The other 5:

And I think when i took off the intake manifold, coolant fell where the first intake valve is (Cylinder #1) passenger side

And clean and brand new looking under the valve covers

Im still wondering about my coolant issue. I removed the thermostat to check it and that thing looks brand spanking new. At least I know what my shaking at idle and at temp comes from. What is the culprit ? bad valve seals ? Not seated right? Im a noob at anything about valves,heads

 

[BrianSD_42]

And I think when i took off the intake manifold, coolant fell where the first intake valve is (Cylinder #1) passenger side

Ok so I am a little worried now. I am no mechanic but I did suffer a cracked head last year.

Even if coolant "fell" into the cyl during the maintenance, it would have burned off long ago. That must be new coolant, correct?

If true that means you could have either a cracked-head or head gasket.

:vader:

 

[LittleCaesar]

Over $500 for two O2 sensors? The ISC/IAC was replaced twice? It sounds as if the replacement engine was bad from the get go and parts were just thrown at it to get a fix.

 

[Drcoffee]

Wait, is it just a bad intake valve seal? How else would you get so much carbon around the valve stem? Weak/broken valve spring

 

[got_rwd?]

UPDATE:

Pulled the heads off with my family member
Bad gas seems to be the culprit causing build up on valves causing cyl #4 not to seal properly. A bunch of gunk built up.


Coolant leak:
Very small leak from water pump
the actual major leak was coming from a bad gasket on the water by-pass pipe
(metal pipe under intake manifold from heater core to block). There was a build up of rust around the leak. Its been leaking for a while.


Work being done:
New gaskets top end
head rebuild ( $220 per head ) :moping:
water pump and gasket
new radiator (cracked the other one, bottom bracket was rusted out)
all new hoses and vacuum lines
*timing belt and tensioner/thermostat are still brand new

FUN:
Repainted valve covers army green
Repainted timing belt cover army green with black 5VZ lettering
Repainted upper and lower intake manifold black
Repainted all brackets to oem black

We will see how she purrs

 

[got_rwd?]

Got my heads back !

Machine shop says bad gas caused bad valve seals and gunk build up. I guess previous owner was pumping at a crappy gas station

Heads werent torqued properly at rebuild was another culprit.

Heads were rebuilt, deck and pressure tested for cracks for a tune of $468
:cry2:

Here is a pic of the block . You can tell where the coolant leak was at (front center at water bypass tube seal). Rust build up and the first cap is clean.