Clean your MAF. Should fix your idle problem. While you're at it, clean the TB and change the pcv valve and you'll be in good shape.

 

Wow. I never knew that. I just assumed it was the sensor, since the owner's manual says 20. Whenever I fill up, the needle never goes all the way to the F line. It's just below. Makes sense, I guess. That or Scraggle gets a laugh by running people out of gas. :-P

 

Good call. Just be careful not to mess with the butterfly valve when cleaning the TB.

 

Haha, I wish that were the case. That would be funny. But, no, I took it to the limit one day.

 

Okay so I topped the tank off today so I can chart the mileage since I did the tuneup. On the "as far as I can tell, nearly useless" fuel gauge I was at about 1/3 of a tank. I topped up with 10.70 gallons. It never went all the way to the top either. Didn't notice that the other day. Go figure.


Before I disconnected the battery yesterday I had about 165 miles on the trip odo, then did about 12 more before the fill up....so I'm looking about 18mpg roughly before the tuneup.


I know the engine is pretty healthy, while the plugs were out I did a compression test. From 205-211psi across all 6 after sitting cold for a full day. Valve cover tube seals leaking in 4, 5, 6 so that is the next job.


The MAF is mounted in the K&N Typhoon cold air intake. Can I use regular CRC Mass Air Flow cleaner on it? Is there an external idle adjustment? or will MAF cleaning bring the idle up?


I have an OBD2 scanner and read the SES/MIL that popped up again. O2 sensor, bank 1 sensor 2 (downstream) heater circuit low input. There are all new sensors in there. Wondering if I have a wiring issue. Being that it is a downstream sensor, in Ebay headers, with no cat convertor.. will this affect the ecu..limp..reduced performance..etc? or is it just annoying looking at the light?


Sorry I'm just full of questions. Thanks in advance to the gurus

 

check out these plugs





one more question, what do I order, and any suggestions where, to do the valve cover/tube seal gaskets. Do I need a plenum gasket set as well?

 

CRC is what I used. Also, make sure all couplers from the filter to the TB have to leaks and are tightened. Any unmetered air can eff up the idle.

As far as plenum gasket, its metal and reusable.

I don't know much about catless systems; someone else will have to chime in there.

 

this "system" is ebay headers, then it goes to ebay exhaust that for some reason after the turns and right by the flex joints is cut and re-welded, with some leaks. then from there when it converges, a straight piece of pipe is welded in. no emission inspection in SC.. I'm debating on picking up another exhaust and a hi flow cat just to tone it down and put some low end torque back in the system. and to keep it green.

 

That's actually exactly why I don't know about the catless systems; I think it's irresponsible, but I'm not gonna try to push my opinion on anyone. You can find low mileage OEM cats for ~$150 all day and then get a superior catback system and I think you'll be golden. Unless you plan on getting a high end catback anyway tho, you don't want HFCs. They sound like crap unless you have a quality build behind it. Look up HFCs with stock exhaust..disgusting. Haha.

 

I'm finding a lot to re-do on this car to meet my standards. I cannot believe that someone would go so far to mod a car, and never touch the spark plugs!
Not sure what I'll do for a catback, definitely some changes in store. I like a smooth rip sound, with little to no drone or rasp..so I'll be checking around.

 

Welcome to the 'previously owned by a ********' G35 world. Haha

 

That accounts for like 90% of the used Gs on the market.

 

greeeat.... well, misery loves company. I appreciate the advice

 

So I have been busy buying up parts lately. Going to reinstall the stock cats (thanks Venom), picked up some other headers to replace the catless long tubes on the car now. Got the cleaners for the MAF and TB, and new VC gaskets and some RTV for the tube seals. Grabbed a pair of Cam pos sensors to do while I'm in the area. And I didn't do any of it today..lol


Today I reinstalled the front lip spoiler that got ripped off in a puddle the day after I got the car in our torrential rains. That was it.


Yesterday I installed the spacers (15/25) that I got off here. Had to swap out the front studs for longer ones.. piece of cake. Seriously never did an easier one. Unfortunately I need more spacer up front, the 18/9 +43 Volk is still sunk more than I'd like. But that's not the end of the world.


I'll try and get some pics tomorrow

 

Continuing a part buying spree, i have a fresh set of motor and transmission mounts on the way. All should be hitting my door about the same time, Thursday this coming week I hope. I decided to do the mounts after researching the header install and finding that I will most likely be lifting the motor anyway. No biggie, I have a hoist.

This might solve a few issues too.. shifter shakes a bit more than i would like driving down the highway. i think the longtubes are vibrating off the floorboard sometimes when i get on the gas, especially in a turn. Mounts should clear that up if so, not to mention losing the longtubes anyway

Long list for that day so far, but manageable if i plan it right.
-remove upper plenum, TB
-remove coils
-loosen/remove mounts, lift motor and suspend. loosen old longtube headers
-loosen steering column knuckle
-remove old headers
-reinstall new (used) headers and cats
-install new mounts and drop motor back down
-remove valve covers, clean, install new gaskets and RTV
-reinstall coils
-clean all grounds that I can see and reach (learned this from the Porsche)
-clean TB, MAF and plenum, reinstall

-attempt to complete the reset procedure for the ECU/TB/Idle..etc probably til I'm blue in the face.

hopefully this all goes according to plan. i do know that i need to pick up some gaskets for the headers and cats yet. and some bolts that I think are missing from the headers onto the head now.

*fingers crossed