major loss of power.. any suggestions?

[run4yota]

ok so i had a CEL for a long time (code 71) i found a bad vac hose, and replaced it. code whent away, and i started to notice a power loss over 2 weeks. then the CEL turned back on.. code 25 (lean). i tested the MAF, TPS, ECT, sensors.. all are ok. i also checked the EGR, all ok. the obvious thought was hey the o2 must be bad. i replaced the o2 sensor and she still runs rough with no power after resetting codes. i checked the timing (which was spot on a month ago) and it was at 35 degrees of advance! when i try to bring it back down to 10 deg it starts running REAL rough.. and the lowest i can get it to is 16 degrees advance.

WTF? how is this possible?

could the fuel pump be going out and causing the lack of power?

how did the timing get so whacked out.. any suggestions?

thanks in advance

 

[SV_Dude]

I could be wrong but I would think that the 4runner would not run at 35* advanced. That's WAY excessive! I would start looking at testing your ignition igniter, spark plug wires, and possibly the ECU. Check out the FSM, there are pages in there that will tell you how to test each of those items.

 

[run4yota]

yeah that's what i was thinking.. i was like how can this engine run that far off? and when i set it to 10 deg it sputters and runs like crap! i also noticed that at about 23deg it seemed to run good, but once i hit 3k rpms the truck suddenly jolts and boom good power like new (this is the knock sensor kicking in) i'm wondering if the timing belt possibly jumped a tooth or the distributor has some play.

 

[Clone of the Mean]

Sounds like you need to find TDC and start from scratch..... I had an old chevy that would alternately go from sloppy to Indy car smooth. Turns out the distributor clamp came undone. It would jump around and change timing.

Pull the no.1 plug and reset the timing. Good luck.....

 

[Edp]

Did you check the air intake hoses between MAF and the intake? I had a substantial drop in power and the cause of that was un-metered air due to a cracked hose. At idle it would run fine, when you accelerate, the torque of the engine would cause the crack to open up allowing un-metered air, power drop and running lean. I replaced the air intake hoses and the problems went away.

 

[run4yota]

i have an aftermarket intake.. i checked.. no leaks.. but one thing i did notice was a TON of oil in my intake and throttle body and my filter was 30% saturated!.. driving with it so leaned out has caused the oil to thin out and leak everywhere i suppose. it wasnt like this 2 weeks before the problem when i was cleaning my k/n filter. i may take the timing covers off and do a check.. maybe tensioned is bad and caused the belt to jump. or the distrubutor to woble.. thanks for the insite, i will check it out and see what i find

 

[run4yota]

bump.. i need some help from the guru's.

so i checked the valve timing, the timing belt had jumped 2 teeth from a piece of a ball bearing i found in the timing cover. i set it back to the proper timing, and now she's running at 10 deg TDC and alot smoother. so here's the kicker... when the engine is cold it runs great! good power, smooth running, just likeit should be, but then as it warms up it gets worse and worse and then the CEL light pops on and it runs just like it was before... SH1TTY!

any suggestions? has anybody had this happe before? it started right after i replaced the fan, shroud, pulley bearing (where the ball came from), and then both valve cove gaskets at the same time.. i'm so frustrated at thispoint that i dont even want to look at the truck.

 

[Hyde802]

Have you checked compression?

 

[run4yota]

compression is good on all cyl (only 3k on the new rebuild)(which btw cost as much as a 3.4 swap and i am still having a$$ loads of issues with it)

but here's the latest. i cleared the code again and filled it up with 89oct gas and it is running decent.. def something still wrong, and i struggle to hit 70mph, but it is at least drivable.

about 25 miles down the road the check engine light comes on and it goes into "safe" mode. i notice a mild drop in performance but still drivable. i checked the codes and it came back with a 25 (lean code) and a 52(inerruption in knock sensor circut) the sensor and wire were replaced less than 3k ago.. so i'm stumped. i'm wondering if the 89 gas in the az heat just isnt good enough and causing it to knock. i almost always run 91 in it (the 3.slow needs all the help she can get)

any suggestions?

 

[hellsbells]

yes



22RE

:jk:

 

[Hyde802]

If the code is telling you knock sensor....it might be worth it to check the wire out. Sorry if thats now what you wanted to hear.

 

[Arnie19]

We had a big power loss on a 22rec and it was the timing chain had jumped time .The guides and stuff that keep it in line are cheap plastic and was all busted up .It would still run but no power and would accelerate slow .Arnie

 

[Arnie19]

The fact that your timing is way off all of a sudden is a dead givaway to timing chain problem.Arnie

 

[Arnie19]

The fact that your timing is way off all of a sudden is a dead givaway to timing chain problem. Could also be a plugged cat but im guessing timing chain. Arnie

 

[run4yota]

the timing belt was off, it had jumped a tooth so i reset it and runs much better now but after an hour or two of driving it will kick on the cel and then within another min or two start running like shiz. i also notice that the valve cover gaskets start to pour out oil around the same time i get the lean code.. i'm suspecting that it's because the leanness is heating up the heads and the oil...

the 22re doesnt sound like a bad idea.. i'm about to dump this engine and do a 3.4 or a 350 swap... 350 would bt tricksy... but yeah buddy would that be a head turner.

 

[run4yota]

hhhmmm nobody?

i also have noticed it's intermittant. it will run good, then bad, then good then bad... WTF?

 

[Jami_]

hhhmmm nobody?
i also have noticed it's intermittant. it will run good, then bad, then good then bad... WTF?

:iagree:

I bought a 91 with blown motor....swapped in a 96....rebuilt from cams up...replaced knock sensor and wire....along with MAS....timeing was kinda high after about two days of running great then adjusted it and BAM CEL is back on with error code 52 back to the same ol power loss sputtering in the morning and sh*tty gas milage.....whats the deal??? any help would be GREAT

:wtf:

 

[run4yota]

ok so i found the gremlin.. i wanted to post up my solution in case anybody else has the same problem.

so i had the loss in power, and kept getting a lean code. i finally found out that the timing had jumped a tooth after fixing this i noticed A major difference, it felt like i had 80% of the stock power. i did notice that i had a steady miss, oil leaks (after replacing the valve covers twice), horrible gas mileage, and my air filter was SOAKED in oil.. i mean SOAKED!

i took off the breather hose and there was smoke and vaporized oil coming out of it. i figured i must have fried the rings from running lean so i decided to do a compression check (expecting the worst considering i have less than 3k on this motor since i COMPLETELY rebuilt it) after pulling the plugs i noticed that the number 4 cyl had a small amount of oil saturation on it (oh crap) then i took out cyl 6 and it looked like one big chunk of melted metal and black tar! i knew this couldnt be good so i did a compression test on all cylinders and came up with 125psi accept cyl 6.. it had ZERO! i already know what happened.. the cam being out of time caused the cyl to overheat and blow the head gasket between the oil passage and the cyl. this is what was causing the extreme blow-by, and the miss, and the high pressure on the oil passage is what was causing the oil leaks in the valve covers... wow what a challenge this 3vze is... while i have the heads off swap to a 3vzfe? hmmm

oh and btw the lean code was caused by the bad plug, the plug being fouled caused the fuel to not light. the O2 sensor picks up the presence of fuel and leans out the injectors spray timing therefore making the engine run lean.

hope this thread helps someone in the future.. time to go start the head gaskets... again lol

"people wonder why i drink... then the see i own a 3vze and wonder why i dont drink more"