gow/Godspeed

I bought this truck for cheap with a blown HG
I took it apart and changed the gaskets from the hg up, checked the valves, machined the head, put in new, cap, rotor, plugs, wires, fuel filter, ran lucas feul cleaner through a tank of gas, camshaft timing is perfect (I retore it apart and rechecked it and it all lines up), set the ignition timing to 10 degrees (with jumper) but it is less gutless at 20-25 degrees BTDC,rechecked the wires to make sure they were in order, cleaned the throttle body, adjusted the tps, took the cat of and it was not clogged but I think it has been straight piped through the cat, checked the compression,
it still is gutless and at low to mid rpms under acceleration it sputters bad just before it downshifts then when it down shifts so higher rpms it runs okay but still pretty gutless
please help me out what else can I do?
oh and I also checked for vacuum leaks with starting fluid and also a tube used as a stethoscope
I have wanted a yota since i was like 3 but not so much anymore unless I can get some good advice and get the stupid thing runnin
I had the chance to rebuild a 22r instead I m really wishing I would have

abecedarian

Make sure when you're doing the timing with the jumper that the idle speed changes when you insert the jumper.

You mentioned that you checked the converter. You unbolted it and looked through it? You saw the honeycomb matrix in there or did it look like it had been pushed or burned out? Did you try running it with the muffler disconnected- maybe the converter blew out and plugged the muffler?

Have you tried pulling any trouble codes?

bugs1961

Man, I feel for ya. I did pretty much the same thing to my 3.0 last summer and it's running great. What did you get on the compression test? Should be around 180 psi or so.

Was there wear on the cam lobes?

If the engine has good compression and the valve and ignition timing are good, then use the MFI section of the FSM to test each sensor and injector. Check the strength of spark and test the coil and ignitor.

Something is obviously not right as a healthy engine (even a 3.0) will put out good power and not sputter. Hopefully its not something big. Good luck.

pb4ugotobed

A healthy engine not sputter... sure. Good power, depends on your definition of good. You'll know when it's urnning right. It still won't get out of its own way, but you can tell it wants to... just can't quiiiiiiite do it.

Stupid question... Do you have a MIL? Did you replace the knock sensor pigtail harness while you were in there? You didn't mention that... That totally sounds like it's pulling timing back when you put a load on it. Having that knock sensor pigtail harness is VERY common to go bad... It's REAL F'n hot in there and that wire gets real brittle and ends up breaking inside the insulation (though i've seen the insulation crubmle in your fingers when you touch it). Almost always that will trip a MIL though... if yours still works. When you turn the key on (but don't start it) does the check engine light up?

Hopefully that's all it is. The part is really cheap (luckily). You'll have to pull the plenum, that island in the back, and the intake manifold back off again, but it's doable.

abecedarian

MIL? You mean CEL? we're barely even OBD-I here.

gow/Godspeed

yes it has cel but it is not giving me any codes
the compression was close to 140 all around but I did know that the fuel needed to be shut off and I talked to a local mechanic and he said the compression would be even higher if the fuel were shut off so I am good with the 140
the jumper does not seem to do anything to the rpm but it makes the engine light flash
the cat was straight piped looked like the previous owner weld a pipe on the inside of it not sure about the muffler and I don't have access to a welder
is there a way to check the muff without pullin it
where is the fsa thing

gow/Godspeed

ya it has a cel but it is not pullin codes
the jumper does not seem to affect the rpm but it makes the engine light flash
would the knock sensor cause all this trouble
how much does one cost? and wouldnt it throw a code?
the cat is straight piped on the inside (welded tube) but i dont know about the muff and I dont have access to a welder is there a way to check it without pullin it?
man I hope somethin works soon I am getting tired of fixin and replacin things that arent broken
thanks for the help guys

gow/Godspeed

oops the first reply worked I thought it didnt

TNRabbit

Sounds like knock sensor. MAY throw a code but not necessarily. Aside from that, how does the distributor look on the inside? May be time to replace. How many miles on the engine? That's pretty low compression for the threeveezy...

gow/Godspeed

I looked online and it looks like combined pigtail and sensor is about $300!!!!
ugh I wont have money like that for a while what would you guys say about a used one? any ideas?

TNRabbit

Double check ALL your connections from the pigtail back to the ECU, including tracing the wiring harness, for any breaks/shorts.

RMA

Dude if you have more time than money and are ok with pulling the plenum off twice just go ahead and do the pigtail only and see if that fixes it, if it doesnt fix it then get the sensor and do it again . Most of the time its only the pigtail thats bad.

good luck !!

gow/Godspeed

I dont even have money for the pigtail right now
Abecedarian said something about the rpm changing when the jumper is hooked up for timing
if it dosnt do this does this mean the tps is fualty I checked it all out and adjusted it and seemed fine but man a $35 part vs $150 ssounds a lot better

pb4ugotobed

MIL... CEL... same thing. I'd bet money you have a code 52... knock sensor code.

I HIGHLY doubt your knock sensor itself is bad. The failure rate on the knock sensor itself is extremely low. 99.9999999% of the time it's that little 6" long pigtail harness that is bad. Like i said, in the valley where it sits it gets real hot, there's nowhere for the heat to go, and it kinda cooks that harness. I bet if you pull it apart, pull out the pigtail and look at it, it'll be all crispy and brittle. ANY TIME you're down in that area doing work, do yourself the favor of replacing that harness. Especially now that you just did all that head work, had to move that harness all around, it may have worked fine before, but now you've moved it from its stationary position and broken the wire inside of it.

IIRC the pigtail harness itself lists for about $20. Replace it. Bet you a beer after you replace the harness and clear the code, it'll run like a champ

pb4ugotobed

Didn't see this post. I'd agree with what he said. It will only take you 45 minutes to an hour to do everything.

abecedarian

if the idle speed doesn't change, and the timing too: put a light on the marker and have someone watch as you put the jumper it, if the timing doesn't change, which means the idle doesn't change, the throttle position sensor may not be sending the proper signal to the computer that the throttle is closed. Doesn't necessarily mean the TPS is bad, but maybe just needs a little adjustment.

pb4ugotobed

Problem is here, that the TPS in these trucks isn't like others where it's a variable signal. It's either at IDL or not at IDL. If the TPS was out of adjustment it probably just wouldn't idle worth the chit, and probably stall or at least real close to it. He's complaining of a low to mid rpm chug and slug which would eleminate the TPS in my eyes. Hey, anything is possible, however that's not the likely cause.

I'd still put money on the knock sensor pigtail.

Use a jumper wire between TE1 and E1 and then turn on the key. I'll bet you that your check engine light flashes 5 times, pauses, then flashes 2 more times. Then it will pause and repeat... this would indicate code 52. if so, replace the pigtail, then disconnect the battery for a minute, reconnect it (to clear the code) and call it a day. If it's something else, let us know what code it shows.

Edit: found this to show you which wires to jump to pull your code.
http://www.troublecodes.net/Toyota/

MechanicTony

gow/Godspeed,

I know you probaby don't want to hear this but it sounds VERY much like the cam timing is off. I recommend tearing it down a 3rd time and rechecking everything. These are very particular and the timing marks aren't very clear so it is extremely easy to get them wrong. 1st make sure the pin on the camshaft is pointed in the right direction in relation to the picture.

If you think it'd help feel free to post some pictures of both cams and the crankshaft with it torn down and I'll do my best to evaluate. If you wait a couple weeks or so I could probably post some pictures of a 3.0 torn down, I do them pretty often at the dealership.

Good luck good ing,
Tony K

yota_mota

I had a knock sensor go out, but the harness (luckily) was un-crispy thank jeebus, but I found a new sensor on rockauto.com for a decent price. I guess I was part of that .oooooo1%. To check the sensor however, sucks because you have to pull everything off down to the intake manifold, just to get the sensor out. Good advice though.... carry on!