Another Supercharger Idle problem thread | Starting to get desperate

[NissanTracker]

Originally Posted by TheFLiP

Have you checked your cats? I ended up replacing the engine because my tune was too rich for the cats and it melted it and sealed it up...

I went and got headers and test pipes to go with the new engine. Worth a shot?

Sent from my SM-G975U using Tapatalk

Interesting, I would think that going too lean (increase in heat) would cause the cats to go. I have a lift at home, so i'll put it up this weekend and check the cats. I used to have HFCs and I blew through those. I put stock cats on and has only been 1K miles tops on them with the S.C. Cats have 50K miles on them. I have been planning on using some testpipes and welding on some Cats from a v8 or something.

[TheFLiP]

Originally Posted by NissanTracker

Interesting, I would think that going too lean (increase in heat) would cause the cats to go. I have a lift at home, so i'll put it up this weekend and check the cats. I used to have HFCs and I blew through those. I put stock cats on and has only been 1K miles tops on them with the S.C. Cats have 50K miles on them. I have been planning on using some testpipes and welding on some Cats from a v8 or something.

I just learned that after I'd melted my HFCs. Basically running rich has excess fuel that exits the engine and into the cats causing another detonation/combustion. In this case, it's a lot hotter than the exhaust since the cats are having to deal with direct flame which exceeds it's heat tolerance and causes it to fail.

When HFCs failed, it sealed up and blew back debris into the engine. Hopefully, this isn't the case with you.

Sent from my SM-G975U using Tapatalk

[NissanTracker]

Originally Posted by TheFLiP

When HFCs failed, it sealed up and blew back debris into the engine. Hopefully, this isn't the case with you.

hmm... there was a light bulb for a second there. But, i had the hot idle issue with the HFC's before one of them blew up. I probably should have done a second leak down before going to the A-A kit. I did one before the supercharger set up somewhere between 40-50 miles just to be sure.

[NissanTracker]

Check list for the weekend:

1) Pull the front bumper off again. Drive around and do a boost leak test while still hot.

2) use a vacuum smoke tester and pressurize the exhaust system, check for leaks. If anything, would be at the manifolds at this point.

3) Put the Z on the lift and pull the stock cats out and examine.

4) inspect the Fuel pump assembly. Have a new basket + pump and will re-install.

[NissanTracker]

Still have yet to do this, clutch burnt out and it's been super hot here. Work got busy as well.

[NissanTracker]

So... Have most of the Z apart to take the transmission out for the clutch replacement. Just waiting for a transmission lift to arrive in the mail. While I had it on the lift, I took a look at the cats. I did not remove them yet, but I noticed on the passenger side, the cell is loose. As in, I can pull it in and out with my fingers.

I'm assuming this is bad?

I'll take them off once the transmission is off and see what they look from the upstream side.

[TheGreyZ]

Is your Z a 2007 by chance?

[redondoaveb]

Originally Posted by TheGreyZ

Is your Z a 2007 by chance?

It appears so

[TheGreyZ]

You probalbly need an 08 ecu. I had idle issues with my 07 after my turbo and my tuner said that the newer 08 ecu was able to correct throttle body and idle issues more than the 07 could.

[NissanTracker]

Originally Posted by TheGreyZ

You probalbly need an 08 ecu. I had idle issues with my 07 after my turbo and my tuner said that the newer 08 ecu was able to correct throttle body and idle issues more than the 07 could.

Interesting. I think it is more of the ECU ROM type. Each ECU type has different features. My 07 Nismo ECU is EVC12

https://uprev.com/romlist.php

[NissanTracker]

Originally Posted by TheGreyZ

You probalbly need an 08 ecu. I had idle issues with my 07 after my turbo and my tuner said that the newer 08 ecu was able to correct throttle body and idle issues more than the 07 could.

Well, you were right. Seb set me up with a 2008 ROM and fixed the issue.

[NissanTracker]

UPDATE:

So clutch has been switched out. Just have to put the tranny in when a set of OEM cats come in tomorrow.

I examined the cats. Besides the passenger side down stream cell that was loose, all seems in order. No clogging/melting at all.

Seb did give me a possible "Eureka" tune that addresses idle. Can't do much with it still car is back together.

Next year, I will possibly modify the exhaust. Put some resonated test pipes and put a couple of Mil-spec cells on my motordyne TDX2, possibly on the Y section of post muffler. Spent too much $$ this year.

[DOOMMONKEY777]

Sounds like a vacuum leak, umm disconnect all the vacuum hoses from the intake manifold and pug every thing up, start the car and see if its still doing the same thing, if its nice and calm ~700 rpm, turn it off and connect a hose back with a new metal non OEM tie thats proven to work, start it up and check for problems, continue until you find the one that is leaking.

[NissanTracker]

Originally Posted by DOOMMONKEY777

Sounds like a vacuum leak

Boost leak checked and all is good.

[NissanTracker]

Update:

Finished the clutch install... Finally. I'm only able to put in hour or 2 there and there. Married with 2 younglings takes my time away. Went with the Zspeed stage 2 quiet setup with steel flywheel. Upgraded to a Wilwood master. Can't wait for the throttle response change with the lighter flywheel.

Also got a tune from Seb for the idle. Guy has been pretty solid this summer. Have to fill up the tranny and bleed the clutch tomorrow, but I'll flash it some time this weekend.