Hi I did a engine swap in my 04 350z and swaped with same kind of engine but with just less miles. I had to tak everything off from the old engine like the pully'sand everything else . bBasically the new engine was just a small block with heads on it. It TOOK ME OVER 4 WEEKS to do because i could only work on it on the weekends because i had to work. Now when i try and start the car it wont start or will start up and idle real low and ruff and then dies after about 20-30 seconds. I have gone over each wire and rechecked all connections and can't find anything wrong. I even had a new timing chain and tensioner installed and it was put in at top dead center and timed correctly. Do i need to do any relearning procedures for the engine/ecm? Please help you can?

 

Relearn the electronic TB. I have no clue how to do it.

 

Do you think it could be any of the camshaft sensors or the crankshaft sensors? Even though all the sensors worked just fine on the old engine and i pulled them all off it and put them on to the new engine?

 

I have drop the transmission thinking maybe i installed the flywheel wrong and installed it correctly this time, it is in the right dowel pin hole. And I put everything back together and my Z still will not start. It's cranking but does not turn over. I also even bought a new crank sensor from oreily auto parts. I even did a compression test just to make sure all the valves were good and everything was good with that. Please anybody i need some help??????

 

I'd ask if your MAF was plugged in, but I assume you checked that. I've started my car once without the MAF sensor plugged in, and it did as you describe "starts, idles badly, then dies in 20-30 seconds." Maybe clean it?

Are all the sensors the same as the old engine (ie you know they work fine), or did you replace any with autozone sensors or non OEM parts. Ahh saw you bought an aftermarket sensor... if your original sensors were known to be working fine before this engine swap, re install all original sensors. Store bought sensors/ignition coils/thermostats are often finicky. I do have autozone camshaft position sensors and crankshaft position sensor, but things are hit or miss with those stores parts.

 

I did just replace the crankshaft sensor with one from Oreily auto parts. But I did try and put the original OEM crankshaft sensor back in and see if it would start and it would not start with either crankshaft sensors. And yes the MAF sensor is plugged in. I just don't understand?

 

Wait, it wont start? I thought you said it starts, and just idles badly before dying?

Try these:

http://www.technosquareinc.com/350reset.htm

 

It use to start and idle rough for about 30 seconds and then would die or if i just kept pumping the gas pedal it would still run rough for about a total of 60 seconds and then would die. So i took it up to nissan and they told me that both camshaft s were off about 35-45 degrees. So i took it to a shop and had them put a new timing chain and tensioner and set the timing. And when I came to pick up the car it would idle rough for about 30-40 seconds and die. But if you pushed on the gas pedal it would die immediately. So i trailered it back home because the shop did not know what else was wrong with it. And I have been doing so researching online of other things that could cause timing issues and saw that if the flywheel was installed incorrectly would cause the car to not start either. So i dropped the transmission and made sure the dowel pin was in the correct hole. The flywheel alignment and correct dowel pin installation information i pulled from online, where it showed how to look for the alignment hole on the flywheel and then showed which hole was the correct dowel pin hole. But now it cranks and wont turn over at all.

 

Please help?????

 

it is 100% absolutely impossible to diagnose over the internet we have no idea what you have done and havnt done, we have no way to verify the cams where done correctly the second time or if they where screwed up again. it could be a sensor was damaged on swapping the engine(short block btw, small block refers to domestic v8's), we dont know if the TB was damaged, there might be a vacuum leak, something might have gotten in fuel system and clogged the fuel system(doubt it), there could be signal interference if you messed with the wiring during the install and the pedal sensor is telling the ecu the TB is opening but the TB isnt actually opened. WAY too many things that could be wrong in order for us to help we would need EXTENSIVE video of whats going on as well as every test you have done so far. pretty much you need to take it to a shop that actually knows what they are doing. sounds like the shop you already had the car at really didnt have any idea what they where doing which tells me the cams are likely still fubar.

 

If this rough idle sounds anything like misfiring check your injectors.
I bought a used z engine and for some reason it came with different injectors
And when I first started it , it would barely run and misfire.

I was able to tell by shining a flashlight thru the port in the front of the engine just under the lower intake, you should be able to see the injector for cylinder 1+2, check the color make sure it's the same as your old engine. My old engine had purple injectors, the used one I bought had greenish ones.

Just a shot in the dark here, hope it helps.

GL

 

he only swapped either a short block or long block hard to tell from what he has said so he is reusing his injectors.

 

It would at least help to know the previous engines health/symptoms or problems for whatnot was replaced, and what parts were reused or replaced (especially sensors/ injectors/ignition coils/spark plugs/gaskets).

 

It was a short block that went up into the V with heads on it. And that was all that was on it. I literally had to take everything off the old engine and put on to the new engine. All pulleys and everything under the front timing cover , I did have a new timing chain replace and new timing tensioner. The coil packs were from the original engine and I am using my original engine bay harness. Now the reason I did the engine swap was because my original engine had 107,010 miles on it and I know that's not much but it was leaking coolant into my right header because of a bad head gasket. So I decided if I was going to pull a majority of the engine out to just fix a head gasket, then I might as well just pull the hole engine and swap it with a engine that only has less then 5000 miles on it that I have been saving for just in case. Now since I had the engine out I did install aftermarket headers on to the new engine also. I did reuse my original injectors and plenium and I reused all wiring and sensors from the original engine. Now everything was working and running fine on the old engine just fine. Again the only thing that was wrong with the old engine was tge bad head gasket other then that tge car ran great. That's what I don't understand why it this engine won't fire up perfectly. Because everything I pulled and swapped from the old engine and put on to the new engine was working great before. I probably should have just left the old engine in there and just replaced the bad head gasket but I thought I was making a better decision in just installing a new engine with less then 5000 miles on it. And I also made sure before I purchased the new engine I took it to a shop and they even said the new was in great working order. I just don't know what else to do other then take it to a nissan dealership again in indianapolis.

 

Oh and both engine's are a VQ35DE 6 speed manual.

 

Also tell me if this is the correct dowel pin hole on the back of the flywheel. Because this how I installed it, by using the information found online. This is the link to the web page showing how to find the correct dowel pin hole that i used. please let me know if this a correct way of locating and for install?

http://www.brakeandfrontend.com/Arti...tallation.aspx

 

cant say on dowel i have only done the JWT flywheel which mine only had one locating hole.

are you sure the cams where installed in correct location? not only are the intake and exhaust cams specific they are also left and right hand specific according to a couple things ive seen in the fsm when using stock ones.

thats where my money is that there is still something wrong with the cam timing or placement.

 

Thank you I really appreciate all the help....

 

Can you tell me is there any way for the cams to be off if all the markers are lined up with the cams shaft chains and all markers line up on the timing chain?