DontknowZ's

Hey guys. Just replaced my headgAskets and all the other seals and gaskets and now the car turns over but won't start. So I took off the chain cover to check the timing and it all lines up and seems to be on the compression stoke. I need some help on what else to check, or how to make sure my timing is right on. I could really use any suggestions. Thanks!

hulkout

Timing was my first thought too. Triple check that, my friend. Do you have a factory service manual?

DontknowZ's

I did get the factory service manual and everything is set right. Just not sure if I'm on the right stroke? I have a guage hooked up at cylinder 1. I don't know how to check my timing to make sure it's right

hulkout

You can tell by looking at your cams. With the crank pulley timing mark aligned, The intake and exhaust cam lobes on cylinder 1 should be as shown on page em-50 of the fsm. (That's where it is in my 03 manual for a vq35de anyway. I guess I don't know what year your z is). The exhaust side is at about 2 o'clock and the intake side is at about 10 o'clock. If so that is the compression stroke for #1. If not, then you need to turn the crankshaft 1 full 360* revolution and check again.

It sounds like you still have your pkenum and valve covers and everything on. That sucks. But that's the name of the game. With my luck, it's not done until it's done twice. Or three times.

I'm not sure how to decide what stroke you are on using a compression tester...

DontknowZ's

This is my first z so when I took everything apart I cleaned the Pistons so I brought each one up to Tdc to clean them then when I finished cleaning them I just set piston #1 to tdc not knowing which stroke it was on. So with the heads back on I just had to turn the cams to face each other with the dowels facing up then I allined the chain on the gears and slid the sprockets on. After all that the marks on the primary chain all line up (the 2 gold links at the top and the red line on the crankshaft pulley) and figured it was good- but no start. Could I possibly need to take the chain off the bottom, spin the crankshaft 180* then line it all up again?

hulkout

I think that sounds correct to me.

So if you're sure of timing, let's look at basics. Did you drop any sensors? Damaged Cam or crank position sensors might cause this.
Are you getting spark?
Fuel?
Are all of your throttle body plugs in tight?
Backwards MAF sensor? I'm not sure if you can install it into the housing backwards or not.
I'm not sure if the z has a oil pressure/level safety shut off but that could be something to look into.

I'm just throwing out ideas. In my mind, if it was running before the tear down, then you had to have made a goof with something going back together. I doubt it's just a coincidently bad sensor or something. Has to be something you touched. Be it timing or missing a plug. There's lots of plugs....

dkmura

iTrader: (64)

Don't forget something as simple as your battery. Make sure it's fully charged and then measure voltage without the charger. You should see 12.6-12.9 at the least, otherwise the engine may crank, but not start.

Be sure to update this post with what the solution is once you find it....

DontknowZ's

Alright so I'm just trying to narrow down the possible faults here. Can anyone tell me if my timing is right? I have some pictures to go with this, to check my timing I hooked up a vacuum/pressure guage to cylinder one and cranked over the engine with a ratchet. The guage showed compression building up as the 3 marks on the sprockets lined up, and the guage stopped reading pressure right where I left everything in the pictures, meaning it's at TDC. Does that seem correct to you guys? Just so I don't put it back together and find out the timing was the case...

DontknowZ's

Timing chain

DontknowZ's

Timing mark-crankshaft

DontknowZ's

Left cam gear

DontknowZ's

Right cam gear ( sorry about the multiple posts, would only allow me 1 pic at a time)

hulkout

I have never checked for tdc with a gauge that way. But it's gotta be on the right stroke of it makes pressure there because the compression stroke is the only upstroke with all valves closed. So you must have the correct stroke. I am not at home to check the manual From memory and what I can see in the pics the main chain looks dead on. Are the marks on the secondary chains lined up?

Edit**. Got home to my manual. To my eye the main chain is correct. So as long as the two secondary chains are aligned I believe you have it right.

Just double check it all again with your own eyes before sticking it together. It's tough for me to see the little marks in the pics.

DontknowZ's

Yes the secondary chain lines up with the marks on the back of the sprockets and on the dowel pins at the end of the camshaft.

Here are some things that I did that might be the problem

- I didnt check for tdc compression when I took it all apart and had to set it when I installed the cams, but judging by the pictures and what I've read. I guess I set it right.

- I took the covers off the VVT sprockets but did not remove anything and put them back in the same spot. Could that have changed anything

-cleaned the cam position sensors with a small tool to clean the sludge out of them.

During the entire process of removal and installation of the engine components I had the battery connected still. Is it possible to need to reset the ecu to start it?

hulkout

And te two gold links are matched to the 2 dots on the exhaust gear? Just being thorough. .

That's no problem. That's why there is a guide on setting it

The book is stern on not taking them apart. But I have cuz I wanted to see how they work. I don't see why it wouldn't at least start. Even if taking them apart did cause a problem.

Maybe? Stranger things have happened.

Again it should at least start. But you could try an ecu reset and throttle body relearn. What's it gonna hurt?

DontknowZ's

Cool. Thank you so much for the quick responses. I'm going to put the car back together, check all the plugs and try to start it with the battery charged. I'll keep you posted with how it goes or especially if I find the problem.

hulkout

No problem. Sometimes another set of eyes can really help. Let me know how it goes. Good luck.

JERZ350

iTrader: (2)

Did you happen to change those timing chain tensioners? May as well since you had the cover off and they can wear out causing startup chatter.

DontknowZ's

I did not. Here's an update... The car won't start but it runs when I give it throttle, and it's rough. Any suggestions???

hulkout

what kinda rough? Is it missing or is it a fuelling issue?

Did you mix up an injector or coil plug when plugging them back in?

Did you check the plugs? plugs don't like burning coolant.

Why did you change the head gaskets? When a head gasket goes it's usually due to an underlying issue. Are you boosted?

At this point it may be helpful if you outline what sort of mods you have.