89 3vze missing on #6

[catbird]

I replaced both heads on my 89 4runner, brand new heads, all new toyota gaskets. It ran smoother that it ever had for 3 days and then began to miss,strange "popping popcorn" noise loud exhaust like noise from the air cleaner area,loss of power, and gas mileage went way down. I pulled each plug wire and when I pulled #6, the rpms didnt change, the popping noise stopped and the engine started just a constant miss. So I compressioned checked #6 and its 150psi. All other cylindars had significant rpm drops when wire removed. my compression is good "thank goodness". I cant see how just one cylindar could not get air and its definatly getting spark, so it must be fuel. The spark plug was very black. Am I getting no fuel on #6 or too much? Im going to replace #6 injector tomorrow with one I saved when I rebuilt the block this spring. I am concerned with the loud sound from the aircleaner area?? When I sharply rev it from idle, its quite loud. Do I have more thsn one issue?
Thanks!!!

 

[catbird]

Another thought,,,, when I installed the intake, I noticed it didn't sit quite level against the head surfaces. I torqued it down anyway, but I'm thinking it cracked when the motor got hot while driving. Plan to pull the plenum this morning and I bet its cracked on the port for #6.

 

[catbird]

ok pulled the plenum, no cracks in intake. replaced number 6 fuel injector and still not running on number 6. there is spark + 150psi compression. i have tried different plugs and different plug wires as well as plugged in my spare ecu..... no changes. with number 6 wire hooked up there is a random popping noise that goes away when the plug wire is removed. Im headed to the parts store to buy another cap/rotor although mine looks in perfect shape. anyone have an idea? how do I check the signal for the #6 injector from the ecu?

 

[catbird]

well I got a noid light and it looks perfect just like it should, new cap and rotor. I double checked plug and wire again. It must be something small because Ive checked everything big. I've changed fuel injectors and ecu's have compression, fuel, fire, and I'm assuming air. how could it not be getting air? would have to be to get 150psi compression right?? the spark plug is black as can be, so thats a symptom of the problem.

 

[jynx]

What kind of black is it? Sooty with carbon, or burnt? Any actual damage such as worn electrode or Broken ceramic?

I know that the way the exhaust is routed with the crossover pipe, some times the #6 cylinder will burn the exhaust valve, but from the sound of things you have all new parts and I find it hard to believe that you burnt a valve in 3 days.

Have you checked your manifolds to make sure you don't have an exhaust leak or something?

Timing good? Ever had any problems with bad gas? Or pre-detonation?

Did you check the injector harness? The connector might be pulling out and causing a funky spray, or non at all. I broke over half the little clips on the last set harness I pulled and I ended up zip-tying the together. Will re-pin the next ones I do if I can find the connectors to order

Keep us posted.

 

[catbird]

Thanks I will keep posting. The black is dry sooty black with no other damage to the plug. Yes a few of the connectors are cracked/broken fixed similar to yours but this one is completelt intact. tomorrow I'm pulling the valve cover and having a look, Im wondering if the exhaust shim spit out of place and that cylindar cant release to the exhaust manifold and is blowing back thru the intake valve when it opens. Timing is good or was because I have moved it trying to diagnose the thing! My plan is to check the cam position if everything looks good under the valve cover. It is possible one cam jumped out of place but it was running so good and its a new belt with no slop. The exhaust is sealed up good. At this point Im pretty convinced the exhaust valve isnt opening, thats the only thing that fits all the symptoms.

 

[catbird]

Wow! get this! There is none, I mean none of the cam lobe for #6 exhaust there. Worn away? these are new heads! Has anyone ever seen this before? Is there something wrong with that valve/spring bucket? Im going to replace the cam with one of my old ones and check that the valve moves up and down. The cam bucket rotates freely with finger pressure now below the non existant lobe. Also,,,,, that lobe went somewhere so I have a few ounces of steel ground up in my oil. That cant be good!

 

[jynx]

Do the rest of the cams look new? I had that happen on my truck several years ago, but thy were old and a couple of the oil passages were clogged and it had worn down over several years.

I would talk to your supplier, sounds like you got a botched cam. There is no way 3 days would destroy a cam. That would explain your problems and I would make sure you don't have some oiling problems. Could be from the heads being machined. So how did the cams look when you dropped on the heads? This whole deal just sounds bad for the head builder. You did use plenty of assembly lube and oiled things up good before you did the start up, right?

Will be interested in how the old cam does.

 

[catbird]

It runs great again now atleast for now. Smooth as can be with the old cam. There was oil evreywhere under the valve cover, so I dont think it was a oiling problem. Botched hardening on the cam is what I think because there is a definate difference in the appearance of the cam on the end at #6 exhaust lobe. I took some pics and will post them up tonight. I hav'nt posed pics in threads yet. Im definatly going to call the supplier. I think refunding the money on the heads and more would definatly be in order. It seems like the other head is ok for now but, who knows?? It definatly cost me days of diagnosis, money and time. Not to mention the ground up metal loose in my engine will shorten the engine life for sure. I took pics of some of the fragments that I was able to fish out with a magnet. I changed the oil and put a big magnet on the outside of the oil pan. Has anyone had experience with parts suppliers on this level? What should I expect? I can send the cam back but I'm not goin to pull the head to send back if its going to run right.

 

[Bogo]

I changed the oil and put a big magnet on the outside of the oil pan.

My favorite spot for a magnet is the core of the oil plug. Monitorable and cleanable every time the oil is changed, and oil moves slowly past it. Second favorite spot is on the oil can. Theory being the can goes away every oil change so the particles go away too, but you can't monitor them. Also the flow is higher there so particles may just get swept past. If a magnet on the side of the oil pan falls off, the particles go back into the oil. Also it can't be monitored.

 

[catbird]

Cam

The cam on the left is my old one, the right one is the new one with the missing lobe. Both are positioned the same and the #6 lobe is at the bottom, or was there anyway What interests me is the color chage @ the lobe that wore down. It looks like the new cam was never hardened??? I put the magnet as temporary thing on the pan to hold any bits there until I can pull the pan and clean it out.

 

[2ndGenToyotaFan]

Whao..... Fingers crossed man! That sucks!

 

[jynx]

Holy **** that is crazy. The one in my truck was just worn down, not completely rounded.

That is definitely worth a call to the supplier. Not sure what you will get back from the supplier, but I would say you are due at least what the cam was worth and something for your trouble, plus some kind of extended warranty in writing. New 3vz heads are crazy expensive, so I'll be interested to see what they are willing to do for you. If you don't mind me asking, where did you get the heads from?

 

[catbird]

Im going to call the supplier tomorrow and email pics to them. They are Japanese heads and were $320 ea plus a bit of shipping to get them to Alaska. I understand that these things can and do happen so I,m not mad just dissappointed because my decision to get new heads was because I wanted to be certain that I wouldnt have a problem with them!!!! I hope to be able to report that this supplier handled it well and stood behind thier product. The heads certainly looked to be top quality at the time of install. I will post tomorrow evening on how it goes.

 

[catbird]

Quick update..... I notified my supplier and they requested the pics be e-mailed, so I should hear from them tomorrow.