Help with 3RZ Engine

Hey everyone,

I'm trying another avenue of approach here to try and find out what my problem is. Here's a rundown of what all has occurred.

2000 2.7L 3RZ

I had a misfire on cylinder 1 and a random misfire (codes P0300 and P0301). I live in a state and county that requires an emissions check when getting inspected. If your CEL is on for ANYTHING you automatically fail. So, I decided to finally address the issue and began taking my head off after I ran a compression test and I was getting around 70psi on cylinder 1. Once I got the head off I could see that I had a burnt exhaust valve on cylinder 1 and a couple of other valves that looked to be shot. So, I took the head to a local machine shop to have it worked over and replace the shot valves and get a valve adjustment. I got it back and have everything back together (I want to say as it should be, but at this point I could have missed something simple and that's what my problem is) and try to start it up. No ignition. She cranks but doesn't start. A new compression test shows that I have above 160-165psi on all cylinders and I made sure I put the camshafts and timing chain back together at TDC. The plugs and wires are new and the coil packs are fine. I've run out of ideas here and I am praying someone thinks of something I can check. Thanks for reading and for any advice you all may have.

 

don't worry as much as before. your engine is put together properly. and even if you didn't get the timing right, it's a non-interference engine, so nothing else will get damaged unless you run it like that.

when you put the timing back together, did you match all of the timing marks? so long as they're matched, everything should be good.

do you get any codes at this point? see if any of them are showing that you forgot to reconnect something.

 

Thanks undying, for the reminder that it's non-interfering. I'm not as stressed out now. It won't even run at this point so there shouldn't be any damage, unless excessive cranking from testing will do anything. Since I cannot get it to run I also do not have any codes just yet. The timing marks were matched. I have made sure that the crankshaft is at the point where cylinder 1 is on it's compression stroke and lined up the two camshafts with the two dots on the exhaust shaft and the one large dot on the intake shaft. Additionally, on both shafts, the lobes on the front of each are pointed straight up and the three dots are also lining up perfectly.

 

Actually, the 3RZ and 2RZ are INTERFERENCE engines.
The 5VZ, like that of undying, is non-interference.

http://www.yotashop.com/interferance-engine-v-s-non-interferance-engine/

 

Great...So, chances are I've probably bent all of my valves?

 

FUCK!! sorry bout that

but it would only be a problem if you didn't get the timing marks right. besides, the damage would be on the valves, and you wouldn't be getting above 40psi on any cylinder if the valves were damaged. but youre getting nominal ~170-180. you're fine.

 

Well, I'm still not getting those numbers. I've only got up to 165.

 

I wouldn't assume that. Your no-start issue could be electrical or fuel-related.
Have you double-checked all connections, like undying suggested?

 

oh 165 is fine too. i guess you're not used to seeing the tilde "~" used as an approximation sign . so around 170psi is good vs having around 100, 50, or even 20.

 

So you got compression, now you need fuel and spark. Are you sure the fuel lines are on correct, can you small fuel after long crank? also double check all the wiring connectors you touched. Did you remove the engine harness, or what?

 

You need three things to run. Compression (which you say you have), fuel and spark. I would first check whether you have spark. I bet you don't. Figure out why. Crank angle sensor? Cam sensor? Not sure which of these the 2000 uses to tell the computer your are spinning, but one of them does. If you have spark, figure out why no fuel. Doubtful your fuel pump took a crap the moment you removed the head.

 

I do smell fuel when I'm cranking for the compression test. I never touched the crank sensor and as far as I know I never came near it. I did not remove the engine harness but it was definitely shuffled quite a bit while taking things out and putting them back in. The cam shaft sensor was removed, cleaned and put back. Do those tend to go bad if handled too much?

 

The computer only fires the injectors if it senses that the engine is turning. It uses the crank or cam sensor for that information. Therefore, if you truly do smell fuel entering the cylinders, your computer and sensors are functioning. You need to remove a spark plug boot and physically check to see if you have spark. Again, I bet you don't.

CAVEAT: This is how the typical system works. I have not specifically researched exactly how the 2000 Tacoma 2.7 does its thing. For all I know it might use the crank sensor to decide whether to provide fuel and the cam sensor for spark.

 

I just tested, I do have a spark on all cylinders...

 

I would start looking at the timing again and make sure you are not 180 degrees off or something. Cylinder 1 valves must be closed with crank at TDC.

 

I've already confirmed both valves are closed at TDC

 

Spark plugs fuel fouled? Coil harness connectors not mixed up? It sounds like you have fuel (might now be time to check fuel pressure), spark and compression. No obvious reason it shouldn't run. Your thread has now jumped to the "let us know what fixed it" mode!

 

LOL, trust me, as soon as I figure this out I will let you all know. The spark plugs are brand new and are not fouled. I've made sure that the wires from the coils are in the right order (4-1-2-3). I'm going to take the throttle body off and take a look around. At this point it has to be something that I didn't put back on correctly or left undone...

 

check the ground to the motor. you may be getting signal to the coil, but no actual spark at the plug.

the ground for my 2000 3.4 is on the back side of cylinder 5 connected from the block to the firewall and a wire coming from the negative ( i think).

 

I beg to differ. I snapped a timing chain on my 3rz and the valves were perfect still. I think the cams have to be in time or the valves may hit each other but not the top of the pistons. Fortunately since the cams are geared to each other it is a non issue if the marks are lined up.