nate V

yea i did the secondary is ok but i dont think that the primary is...tested them today
although if the egr sensor was failing whould that possibly cause the engin to run too rich all the time..? any input

CyMoN

and you checked your intake pipe after the vafm?
thinking back mine ran like crap
and it was the pipe that attaches to the throttle body had a crack on the bottom out of sight.

nate V

I really is acting like an intake leek but not complatly.
But i will deffinatly take a look at it.
Infact i have a propane torch and look for leeks again.
thanks. i have the feeling it is something so simple that i just keep over looking it. I had it pulged in about a month ago and it came back with a rick/leen reading at start up. I knew that was wierd do i replaced the o2 sensors and that made no change.

SEAIRESCUE

OK, unless I missed it, have you checked for any codes in the computer?

What is your vacuum reading at idle?

What is your timing at idle, jumpered?

Fuel filter?

Sticking EGR will reak havoc.

The plugged vacuum port appears to be right on the throttle plate and may be one of those no vacuum until the plate is cracked. So, if no vacuum on it at idle, moot point regarding operational problems.

Problems with the mass air sensor will throw it into a rich condition.

You really need to jumper the diag circuit and pull the codes.

Report back with your results.

nate V

The codes wouldnt pull out when i pluged in the computer to read them all the it would tell me is the running conditions. It was back and forth between rich and leen every few seconds from start to warm idle.
Vacuume at idle checked out to be with in limits.
The fule filter is brand new i replaced it in spring
The EGR was ok i tested it with a pump and seemed to be working wasn't stuck or anything.
Timing was all the way past 10 like at 15 then i retarded it to 10 like it should be.
Replaced both the o2 sensors, and TPS
I dont know about the VMAF I have 2 of them and neither seem to change the conditions.

Recently today i jumped the EGR with a 15ohm resistor hoping that would help and now seems to be starting fine w/o problums. but still looses cylinders when i place the engine under load or when i change gears right after start up..............? I will go get it plugged in to a comp this weekend hopefully with some revealing information

nate V

next step
I am going to get all the codes out of the truck and replace the coil and igniter since that is the most likely problem before the injectors, ECU , or knock sensor. on theplus side though if i do the knock sensor than i can check all the injectors at the same time right.....just very time consuming.

I want to thank you all again for your input. As you can see im a noobe to this fourm and have found it very informing.

nate V

Humm now I am really confused. Yesterday I got another coil and igniter pack. When I got home I took the old one out and cleaned all the grounds.
I put in the new one.

Can you believe it NO CHANGE so I dont think it was the coil or igniter.

I read in another about a test you can do to see if the knock sensor is working properly by taping on the intake manifold with a hammer while checking the timing and it should retard the spark by a few degrees.

When i did the test i got no retardation ...is it possible that I could have done it wrong??

Repeat symptoms.....@ start up idle is rough and other times its perfect, either way when the engine gets to about 3000 rpms it immediately looses cylinders and slowly dies to eventually stall out. I can keep it running by working the throttle but often times i get a very scary sounding ping of the valves and a backfire through the induction system...I know that means its too lean.....

I took another suggestion I read about yesterday and added another ground from the engine to the firewall since the knock sensor runs at a very low voltage...this did not change anything either.

This is seriously beginning to frustrate me and am at the end of my ability any more suggestions......would be awesome.

OH yeah the engine had a/c in it is there something i could have missed when tearing it out and tore something out i shouldn't have??

thanks again

nate V

Seriously annoying ...Thinking of changing the engine because I cant figure out whats wrong with this one.

Symptoms

When ever the engine is under load or coming back from being under load it looses cylinder and boggs way down.

Removed and blocked off the EGR so its not that.
When i removed the engine it ran great so I know it is something I screwed up somewhere.

Im thinking maybe it is the FPR and the VSV

I recently advanced the timing to 15* and it runs better but not correctly ...the solution just eludes me

Any input would be awsome I am pulling my hair out here......
thanks

Guardian_Saint

Picture to the EGR would help too.

Spence1016

have you done a compression test on it yet?

nate V

No to the compression test yet.

But i have found something that could be the cause.

Pulled the codes and I got a code 21 o2 sensor circuit

Looks like tomorrow I will be chasing wires....my favorite thing to do....haha

MonsterMaxx

Several people have suggested a compression test - for a GOOD REASON. If you haven't done a compression test you are pissing in the wind because you don't know the basic health of the 'air pump'.
All engines are just an air pump, if the pump isn't working right, nothing else you do will correct that. A compression test will let you know if the foundation is OK or not.
The 3VZE is prone to head gasket failures which will frequently do significant damage to the pump's ability to move air.

However after your statement about it dieing at 3krpm, I'd suspect the cat being clogged. An 02 code is also suspect. AFTER doing a compression test, disconnect the exhaust in front of the cat, let it hang out of the way and retest.

Another possible cause is that the electrical lines to the fuel pump run right along the top of the frame and it's common for body shops and wreckers to throw a chain over the frame rail and smash the electrical lines causing low/no voltage to the fuel pump, which of course would starve the engine for fuel. Inspect these wires carefully AFTER doing the above two tests.


When an igniter goes bad it's usually toast. You get nothing. If you were getting NO spark, checking the igniter would be a good idea, with it running, you are wasting your time w/ igniter.

Cyberman

I'm not an expert on the 3VZE (yet), but I had a similar issue when the timing belt was failing, and the timing went out on another car. I would agree with MonsterMaxx on the compression test as well. After replacing a head one time, and the engine didn't start, I assumed everything, except compression. Ended up having the head cocked a little on the dowels, and the compression test proved that. Without compression, you have little to no engine.

nate V

MonsterMax

I feel you have a very good point with the clogged cat. I feel that that would definitely account for all the problems that i am having.

Starts like hell and idles like hell until its warmed up and going but then its great.

Checked the o2's and found that the up stream one is working correctly but no so sure about the down stream one. It acts funny when i have it hooked up to the multimeter. It honestly acts like its doing the same job as the front one....any thoughts? maybe crossed wires in cab?

When you suggest removing the cat and doing another compression test is this because you think that if it were clogged that the compression would be too high?

Also I tested the fuel pressure and is working properly. 38-44psi idling and doesn't go down after left on there for 10 Min's with the key off. no leaky injectors, thats a good thing.

Question
1 Is the up stream o2 considered the (HOT o2)???? or are they both considered to be hot?
California emissions just to clarify.
2 Are the o2's supposed to be working the moment that the engine starts or are they meant to begin sending info to the ecu after they hit like 700*??


This damn thing is taking me forever have like no time to work on the rig because I am a full time student. Thanks for your patients all your help guys. I greatly appreciate it and have definitely learned a substantial amount about my truck in the past few months, GO YOTATECH !!!!!!!!!!!!!!!!

nate V

Latest update

did a compression test a few weeks back and all were within tolerances lowest being 150psi and the greatest being 165psi.
No large differences between the cylinders.

The cause of all my headaches...Blown Head Gasket
which makes sense now when i think back on it. It was probably the cause of the radiator blowing out this summer.....thoughts?
yesterday i discovered that i am definitely loosing large amounts of coolant to burning and not to the oil.

The question i have to ask is do i fix the hg or replace the engine
it were to be replaced should i do another 3.0 i have with 90k miles or do a
22r swap? I think i would need to relocate the engine mounts to do this.

mt_goat

That's good, maybe the bottom end is ok.

Yes, you would have to relocate the engine mounts. I wouldn't swap an old 4 cly in, I'd swap in a newer one from a Taco before I did that.

I'd start by pulling the heads on your 3VZ and seeing what condition your condition is in.

nate V

HUMM I dont really want to fab new engine mounts for an old 22r i guess that just isnt sensible. Going with the spare 3.0 i have might be a more logical choice since i already have it.
With the 90k on it I will prob need to do timing belt and water pump. anything else you recommend be done to the 90'3.0 b4 i swap it.

freerider2012

I'm having a similar issue and getting a code 14 out of mine. Any idea's on what this could be? wires, plugs, cap and rotor are new as is the fuel filter. Idle jumps from 800 or so to 11 or 1200. When I pull off the freeway my truck tends to almost die it idles so low for about 8-10 secs. but never really does. This is a 3.0 v6 motor if that helps.
Could this be a timing issue?