SC'd 3.5L up and running (well kind of)
 

Got the car all finished up and we started it up, but is misfiring. It cranks up and runs for a couple of seconds then starts to bog and dies. We are getting a cel for cam position sensor. At first i figured it was the maf since we had to lengthen the maf wires for the cold air setup on the SC, but since there is a cel for cam position sensor i guess that should be the starting point.


Any suggestions on what to look for? My clip that goes on to the sensor is messed up so the clip will go on the sensor but it will not click to look it on. Could that cause a distortion in the signal if it is not 100% on?

Yes. Fix it immediately.

Also the SC plate sometime will pinch the wire. It happened to me the first time I install the SC and then I modified the SC plate so that the wire can wiggle behind the SC plate. Check & try that

Come on you bunch of know it alls:). Throw some possibilities out there. I will be going by the shop this evening hopefully to try and work on it some more, but right now i have a death date w/ my physics final to worry about.

Here we go again with SOOOOooooo many possibilities to go screwy. You sure don't do anything in easy baby steps...LOL.;)

My .02...

1)Fix/replace the sensor to get rid of the CEL.
2)If it at least allows it to idle with a bit of throttle, check for vacuum leaks and take it to a dealer to have them raise the idle and perform an Idle Air Volume Learning procedure. You can attempt to do this without the Consult, however I'm not sure it will work without the target idle being set higher.
3)If the higher idle doesn't completely fix the stalling, try playing with the anti-engine stall feature on the Emanage.

Good luck man...get that thing re-tuned ASAP and a *DYNO*DYNO*DYNO*.:wall:

I was just reading in the all motor forum that you can raise the idle by turning a screw on the tb. I know this has always been the case on the 4th gen, but not the 5th gen. Now that i have the pf throttle body can i use this method?

This time it really wasn't a option since it all had to be done at one time:). I like keeping things interesting:rollsmile

i don't know i am scared of dynos now:wall:

You can raise the idle by opening the TB a bit, however the ECU will override/fight it. Your only choice is the Consult.

Cams, PF TB, CAI, and 3" piping weren't necessary, but the cams were worth the risk since you can't easily change them later.

You *SHOULD* be, since you didn't even bother to figure out what caused your previous motors demise or at least post the fuking dyno.

IMO, you either had a damaged motor from the water/salvage or it was the tuning. I'm worried if you use the same tuner for this setup.

I think your assuming to much. I am concerned w/ figuring out what happened but imo trying to "find" out what the cause is would be pure speculation at this point. I do plan on tearing down the other motor once i get my car up and running. I know it was spun rod bearing becuase after pulling all the spark plugs from the front bank i found one of the spark plugs had the the prong bent to where it was touching the tip of the spark plug( rod bearing spun giving it enough slack for the piston to hit it)

I am going to get the car tuned by SGP probably.

well would you

1) rig up the 3.5L tb when you already have the pf tb just sitting there and you know you are going to put it on anyways?

2) Cut and hack and re-weld the stock charge pipe when you are planning on using a 3" pipe setup anyways? Hell that would have been more work trying to get that peice of $hit to fit than its worth

3) Without the stock charge pipe you can't use the inlet pipe

[edit]Detonation[/edit] will close the ground strap of a spark plug...
"If the engine has detonated visual signs like broken spark plug porcelains or broken ground electrodes are dead giveaways"
http://www.streetrodstuff.com/Articl...ion/Page_5.php



Good...the other place didn't have a clue IMO.

1)I would have used the 2K1 TB with an adapter.
2) and 3)Yes.

Jumping ahead sounds tempting though, but if issues pop-up, you have more to investigate.

PF TB has a small set screw on the that you can use to adjust the opening of the TB plate at rest. This does raise and lower the idle abit. This will also mess up your TB position sensor, it will need to be reset.

:worthless :

Ouch, hope you dont have to replace that sensor. Those things are pricey. Ive already done that once.

WRONG, that is what happens when you experience detonation.

Never said it wasnt detonation

No that is not what I was saying. Detonation causes that to happen to the plugs regardless of the spun bearing.
Before I got the J&S I would pull the plugs and find the plugs that way and thought that I had the wrong plugs and that they were too long and the cylinder hit them.....I was way wrong. Dentonation is the way that happens.

Your piston can't hit the spark plug in our motor. Remember the pic I sent you of my detonation. I suspect that is what you will find when you tear into your motor.

ooo gotcha. Yea i was reading that long detonation article today and they mention that. The funny thing is though is that it only occured in one cylinder. The rest of the plugs were fine

It can't even with the extra slack in the rod?

That's typical...leanest cylinder typically gets it.

Which of these had the bent plug? Six I'd bet.
<--Passenger side
1-3-5
2-4-6
Drivers' side------>

It will hit the head first...unless you had an easter egg for a piston, it wasn't contact with the piston.

BTW, did I say I'd take your 3L block off your hands?;)

I experienced the same thing (misfiring, that is) when I did the VQ35 swap in Dubbya's car. I eventually traced it to ignition coils not being connected to the right connectors. I had cylinders 1 and 3 reversed. Make sure your shop didn't make the same boneheaded mistake.

Regarding the CEL for the cam position sensor, check the wiring to the connector. Sometimes mounting the SC bracket can stress the connector wiring and you get a bad contact.

thanks stephen. I will check that

That's what I said back on post #3. You haven't checked that yet?

no i was talking about the coils. We already cheack the contacts for the cam pos sensor

you got money:)?

No, what I was saying is to wigglr the wire and make sure it is NOT pinched between the SC plate & the timing chain cover.

:sleep: :sleep: :sleep:

Nope....you'll deliver it too, right?:fart:

progress on this???

well i replaced the sensor and now it runs and w/o the code, but now according to my boost guage i am getting 2hg of vaccum:). So obviously there is a little boost leak somewhere.

How much of a difference in vaccum can cams make?

BTW i am running nismo 3.5L R-tune cams.

Increased cam overlap will affect vaccum...how much I don't know.

Try asking on 350Z.com...

Yeah, what Icey said. But only 2" Hg seems too low to just be a cam issue. My ZX11 has something like 80 degrees of overlap and it has considerably more vacuum than that.

Glad you got it running, though.

So whats the status of this???

Would this be the same for the 3.0 engine, does it matter what coils are in what spots? I was under the impression that they were all exactly the same and it didnt matter what coil you put into what bank.

I believe the front coils are longer. If you put rear coils in the front bank no way will it work.

on a vq35 there all the same length

So on a vq30 it would make a difference? Would side effects of this coil misplacement lead to the car running really really rich and engine flooding?