Nice work, keep it up. This is exactly why i paid more than I should have for an 06 G35 Sedan that was originally owned by an aerospace engineer that passed inspection at the infinity dealership.

While I have some cosmetic issues, the car is mechanically solid and am really glad I don't have to worry about finding stuff like what you're finding. Each new problem you find and post about, makes me cringe for the car. I'm due for a spark plug change soon due to mileage but I'm not worried that I'll find what you found, just... damn.

 

Well to be honest, the service interval on the platinum plugs is around 100k miles. Mine was a little over..and to be honest you would have THOUGHT that someone modifying the car would have at least looked at the plugs at some point. But I would bet that most out there that are NOT modified would benefit from a plug change.

Now today was gratifying. If you have been following this and my other posts, you know that I have bought a lot of parts lately. One of my recent buys was a set of stock injectors, which I had sent to a rebuilder (THANKS Digital Deviant). My idea is that the injectors in my car were leaking/dribbling fuel and not atomizing correctly. The car would surge in higher gears, and would stall when cruising in higher gears if you pushed in the clutch and coasted. The idle was also very lumpy and the car sputtered often. There was no check engine light associated with this, so it had to be a physical issue.

So this rainy afternoon I set up my 12x12 pop up and got to work. I pulled the plenums and fuel rails and the problem was obvious. I didn't snap any pictures but you can tell the injectors were dribbling. The odor of fuel in the intake manifold was strong, and the spray ends were wet with fuel. So much gas that the valves that I could see were very..very clean. I'm going to change the oil next as a precaution, since that much fuel could wash past the rings. I installed the new injectors and set onto the next project..catch can.

I decided to build a custom oil catch can setup since the plenums were so oily and dirty the last time I took them apart. Now 1000 miles later, going in I could see the oil tracking paths again in the lower plenum. A trip to home depot to grab about 15' of braided polyethylene tubing, my old GReddy catch can from another project and some careful planning, and I was done. The catch can has 3 ports on it. 2 side by side, and one 90* at the opposite end. The 2 side by side are from the PCV and the bank 2 (driver side) valve cover. The 90* goes to the fitting on the intake tube, so there is suction thru the can, the oil vapor drops out and is filtered by the stainless steel wool in the can, and clean air is pulled back thru the throttle body. The former PCV fitting on the plenum is capped.

To finish it all off, I reset the ECU and then started her up. Idles like a champ.. no stutter or stumble. Taking it for a drive, unfortunately in the rain, the car is strong, revs are more crisp, power curve is smoother.. it was obvious how fat the car was running. And most importantly..the car longer stalls when popping it out of gear at any speed. Revs just drop to 750 and stay until I put it back into gear.

I used to be able to watch the fuel gauge drop. Now I'm expecting much better than the consistent 18mpg I have been getting. After all, the cylinder compression #s are on point, injectors and most all sensors are new or perfectly functioning. I should hope to pick up a few mpg at least.

Oh and I checked the plug holes and they were dry. No leakage from my fix in just over 1000 miles since the RTV and new VC gaskets. Still holding out to see if it lasts.

 

Last post was so long I wanted to start a second one. I have deduced a couple things about this car and the way it was modified.

I fully believe now that the longtube headers were an economical decision by the previous owner. The injectors leaking like that would have quickly plugged the catalytic convertors. The longtube headers were the cheapest solution to the problem, while adding a little Go to the mix. I think these headers are of the variety that go for around $400 or less for the set.. They have bling factor in stainless steel, they eliminate the stock manifold and cats in full, and they make a little more power.

This would also jive with my theory about the spark plugs, in that the headers weren't added as a MOD rather as a SOLUTION to a PROBLEM. I think that the previous owner (before the guy I bought the car from) was probably throwing parts and money at a series of problems and never hit on the actual problem. I'm very appreciative of my years as a builder and tuner where I learned all these tips and tricks.. and I'm happy to share.

This car did have a ton of mods on it. I'm just on a path to make sure they are all working together now. Nice to be finally getting some positive results. Can't wait to see what the next 1000 miles are like.

Next up for the mod list is a plenum spacer, and a tune. Then it should be complete and I can just relax, drive it and finally finish one of my other damn projects..LOL

 

This is the catch can install. This may be temporary, or it may last awhile. I used this hose and this catch can on my 450hp 2jzgte drift racecar years ago, so I know it will take the heat of this na 6 cyl.

 

Thank you for the updates. I was a really fun read. Good luck.

 

I can only hope it helps someone in a similar situation.

Stay tuned!

 

Half a tank of gas down, and I'm already much better than before. Car has not stalled once, A/C on or off, and it hasn't surged in gear one time. It just seems to run SO much better.

I still need to try and get that leaking midpipe replaced maybe this weekend. It would have been done a while ago if
1. my welder hadn't broken a few months ago and I've been too busy to get it repaired and
2. I was set to borrow a welder last week but instead ended up having an emergency root canal. Fun fun fun.

Looking at these pics, I think I'm also going to fab a heatshield for the intake this weekend.

I want to sell the D2 coilovers off the car, only less than 3000 miles currently. Looking for a set of Koni or maybe Bilstein shocks and probably 350z ProKit springs to replace them. I don't need to be as low as the D2 can go, and the bouncing over bridge joints on my commute is not something I want to continue..lol I guess I'm getting old.

 

How low do you want to be? The great thing about this platform is all the different heights that were built for it (there's a full 2" difference between the g35x an 350z). A 350z pro kit would still put you pretty damn low. Point being that depending on how low you for realz wanna go, you may not have to go with the super high priced koni or bilsteins. Both are GREAT shocks, but most of the time unnecessary. For instance if you wanted a 350z pro kit you could still use 350z sport shocks by KYB. Or if you wanted g35 sedan sport kit, you could be pretty low and use 350z sport shocks or g35 standard shocks.. There are a lot of combos that could work perfectly and save you a bunch of $$$.

 

I think that if I go with the 350z prokit it would put me right where I want to be. I would actually like to take out a little more wheel gap that I have right now, but I don't feel like going back into tuning the D2s.

The ride is actually pretty decent on them right now, if tight, and honestly if I could swap in a lower spring rate it would probably be just about right. At my stage of use for this car though, commuting, non tracked, I'm more at a "set it and forget it" stage.

I found a smokin deal on a set of lightly used Z33 Bilsteins, if that doesn't pan out I'll definitely consider the KYBs. Thanks for the tip.

if I play my cards right, I can sell off these low mileage D2s and break even on the swap and make us both happy.

 

I just paid for a set of very low mileage used z33 Bilstein shocks, and ordered a set of 350z Eibach ProKit springs.


Anyone that wants a slammed stanced G, there are a mint set of low mileage D2s on my car that will be coming off next week.


Oh, and gas mileage has been great. getting ready to fill up the tank again, and I'm already past the point of needing to fill up on the last tank with leaky injectors..still showing 1/8 tank above E.

 

Please post pics (close up to fenders please!) Asap!

 

You mean pics of the wheel gap now, or after I install the new stuff? I won't have that until next week probably.

I may need some stock suspension pieces to make it happen, spring cushions and strut mounts for the rear and strut mounts for the front...

Anyone have stock suspension laying around from installing a true coilover setup that you would like to part out?

 

I got the Bilsteins and Eibachs today, but stupid DST has it getting dark so early that all I had time to do was assemble them.

Tomorrow they should be on the car. I'll measure the wheel gap and height on the D2 before removing them, then the drop on the Bilstein/Eibachs and then again in a few days when they settle. I also borrowed an Eastwood fender roller to roll the lips just in case. Pretty sure I'm going up to 25mm spacers up front.

Stay tuned...speaking of which, I need to get a tune pretty soon.

Just an hks box, the bilstein are in there








Lol...engrish

 

Got the suspension installed today AND fixed the leaking exhaust pipe. Full update coming in another thread. Car feels GREAT now.. actually like the well tuned GT car that it should be.

 

Bravo, bravo OP. I just gave you a 10 second standing ovation for your work. I wish I had your talent, I can barely disconnect a battery cable without screwing something up. I want to work on my car so badly but I just know I'll screw it up.