Stuck Valve, boo hoo

To Pz Tank, pm me, selling for $600 o.b.o. pick up in Bristol, RI
To maineah, yes 0 compression , not my 1st rodeo
other than the stuck valve, engine ran great, no oil consumption, great mileage and clear coolant

 

I thought the 4.0 was a non-interference engine?

 

NOW installing an oil catch can on my replacement motor to keep the nasties off the valve stems. With 260k, there must have been a touch of blow by, ya think?
BTW, no need to remove trans on this '06 off road 4x4 4.0 on engine swap.
12 hours and an $1850 motor from scrap yard, done! Just had to do it as got a new frame last year.

 

It is but only to the extent of how far the lifter moves it. Enough carbon build up or broken spring can exceed the clearance.

 

hey guys, I think Im having a similar problem. I have an 04' 2.7L with 96k on it and just let it sit for 5months. I have a little "cuff" sound coming from the valve cover and air is blasting back out at the throttle body and out the air filter. I checked the exhaust and there's no sucking. it makes me think its a intake valve. I have no CEL.

my idle also revs up abut 20-50rpm when im idle, and only when the truck gets up to temperature

I added a quart of marvel mystery oil to my recent oil change and added a can of seafoam to the last fuel up to see if I could remedy this issue the easy way. I also cleaned the throttle body up real nice, installed new vac hoses, new pcv valve, iac valve, egr valve, checked the VCV and the other solenoids with the battery. I also did a compression test and changed the spark plugs while I was at it; 180 cylinder 1, 170 cylinder 2 & 3 and 180 in cylinder 4 with no plugs in. I also tried a can of air intake sea foam and half the can ended up in the resonators of the air intake because of the blow back

Any other ways to better target this valve with some cleaner?

Any next steps, my mechanic friends are stumped and said i should just drive it.

 

If that's the case it should be running pretty rough.

 

its running very well. This "cuff" sound is driving me insane.. im stumped

 

The truck also came from Kittreh', fellow maineah'. Been replacing every rust free part i can get my hand on in the PNW

 

So compression and/or leakdown test was good, no codes and you suspect a stuck valve? Seems unlikely. Maybe a cam or valve timing problem? Does the 2.7 have a timing belt or chain?

I assume the sound and blowback through the intake and valve cover happens on cold start and after it's warm? Have you pulled the plugs to give them a visual inspection? Might give you an idea of which cylinder or if they all are having issues.

 

Chain.

 

I did a quick search, and there was a case (not a Toyota) where the ICA was installed backwards?
It that even possible on the 3rz?


I’m stumped my man?

 

With compression readings you have you do not have any valve issues. If you had a skipped chain your compression would suck on all of the cylinders and it would have very poor performance.

 

Good luck O.P.

 

The 2.7L has a chain. I found that thread where the IAC was installed backwards but I dont believe you can do that with this engine. all the plugs looked like they had normal wear and I swapped them out for new ones when I did the compression test. The engine is rough at idle when you start it and when its warmed up it seems to idle fine, other than once in a while there is a spike of about 50rpm. Could it be a bad cam or crank positioning sensor?

 

The only drawback to the IAC theory is, the engine doesn't have an Idle Air Control Valve (IAC).
Idle is controlled by the ECU and the Electronic Throttle.

 

the 2.7L has an IAC, I just swapped it out when I cleaned up my throttle body.

 

should the PWM solenoid be firing off all the time? Ive been doing a diagnosis with a vac hose to my ear, in search of vac leaks, and the PWM is firing non stop

 

EDIT:

Never mind My post below. I went back and found that you are posting a First Generation issue in the Second Generation Forum.

You have the 3RZ, 2.7 liter engine that uses a mechanical throttle. And are correct it does have a IAC.

However I am leaving the post as written below as that information is correct for the 2TR-FE Second Generation Tacoma.

**************Original Post Below: **************************


This is a good read about the 1TR-FE and 2TR-FE engines:

https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=4&ved=0ahUKEwjW2c6V1oDMAhVK1CYKHdx2Bg4QFggzMAM&url=https://www.tradebit.com/usr/wisark/pub/9003/Toyota_Hilux_Service_Repair_Manual_Complete_INFO.pdf&usg=AFQjCNF0yftMIU6cMmxpQtWU6qnzYwJVhw&cad=rja

See page 14 of 29 in the PDF

6. ETCS-i (Electronic Throttle Control System-i)

General
1. The ETCS-i is used, providing excellent throttle control in all the operating ranges. The accelerator cable has been discontinued, and an accelerator pedal position sensor has been provided on the accelerator pedal.

2. In the conventional throttle body, the throttle valve opening is determined invariably by the amount of the accelerator pedal effort. In contrast, the ETCS-i uses the engine ECU to calculate the optimal throttle valve opening that is appropriate for the respective driving condition and uses a throttle control motor to control the opening.

3. The ETCS-i controls the ISC (Idle Speed Control) system.

4. In case of an abnormal condition, this system transfers to the limp mode.

 

Engine Control System:

 

I ended up digging through my trash, cleaning my old IAC valve up that i threw out and the cuffing has disappeared. Stupid Duralast crap