and my 300zx is running alright, but on a idle, it can be a little rough, not bad at all, but at times it can be...i dont know, i just dont like having a rough idle'ing car....im changing out the plugs tomarrow evening. i just wanted to see what u guys would recommend me do to...what else should i replace to have a smoother idle'ing z? i did a oil change, and replacing plugs soon too...what else? oh yeah also, just take in consideration, sometimes when i start moving, it feels like the car tends to lag....not like stalling out or anything, but almost like a fuel shortage cutting in and out..i dont knowif my description is well detailed, but thats pretty much all that bothering me...so please helpme out guys....thanks again, oh yeah its a N/A too, if that helps any

cj

 

http://65.75.130.178/showthread.php?t=59296

Writeup to clean the Throttle Bodies and IACV, this seems to be the biggest cause of the problems you describe

edit: Oh and CC this is your writeup so I thought I"d ask before I just jacked it, would u mind if I formatted this writup as a webpage then put it on my webserver?

 

damn, i wanna do this, but kinda worried if ill be doing it right...i dont wanna mess up the car

 

Be my guest..... I'm honored. Sorry about the dirty engine bay.

Following the write-up above is pretty straight forward. The worst that can happen is you'll have to buy another piece of hose if you cut one too short.

I posted the following in another thread. I'm not a fan of double-posting, but I believe these are some fundamental guidelines to keeping your car in top running condition. I hope this helps some ------>>>>>
__________________________________________________ ___________

Here are some of the general tune-up items for the Z. Some you have done. Some you might not have. If you don't have any ecu codes, all of your sensors are in proper working order. If you read the ignition timing from the ecu, with a ConZult or equiv., that is only the programmed timing. You still need to check your base ignition timing with a timing light at the crank pulley and adjust it, if required, by rotating the CAS.

This is basic Z maintenance. If you don't know when any of the following items were last done, they should be done now.

Replace Spark Plugs
Check base ignition timing
Clean air filter
Replace fuel filter
Replace PCV valves
Vacuum test the EGR valve, fuel pressure regulator & damper
Clean the throttle bodies and IACV (IAV) valve

Closely check all fuel lines and clamps for leaks, tightness and cracks. If they're 10+ years old just replace them now. Leaks can cause fires, and insufficient pressure at the injectors in high rpm conditions

Closely check all vacuum lines for cracks, hardness, or being disconnected. If they're 10+ years old just replace them now. Bad vacuum lines are the cause of vacuum leaks which cause all kinds of running problems

Inspect all of the electrical connections for frayed, cracking, loose wires and make sure all connectors are tight. If there are any signs of corrosion, remove the corrosion and apply dielectric grease on the pins. Z'zzzz are famous for having problems due to corroded electrical connections.

Check the throttle cable where it connects to the linkage. 90% of the cars I've looked at, the cable is not properly adjusted. If the cable is too loose the t/b butterflys will not open all of the way. Also check for fraying of the cable.

When you change your oil, look closely at the oil as you're draining it from the drain pain. Look for water or small metal flakes in the oil. What you see, or don't see, will give you a good idea on the internal condition of your motor.

I'm sure there are some things I forgot......

Also, keep in mind, most of the above items will not cause an ecu codes if they become defective. They will cause your motor to run badly nonetheless.

 

yeah it aint that bad, no codes or anything...i probably just need to clean the Throttle Bodies and IACV

 

k now just a few questions about the process of the cleaning for what u have posted

1) when u put the "T" connector of the IACV tube...once its there, u just leave it there, and leave it capped? i dont have to have another tube? itll be alright as long as it stys capped?

2) when u start spraying the carb cleaner into the IACV tube with the straw tube connected, the car should be running? any tips on when spray it in while pressing the throttle? like a continuous spray? or only when im pressing the throttle?

3) back to the "Y" connectors, do i leave the clear plastic tube in, and just leave the cap on after im thru with this process and zip tie them, on both sides? and when spraying into the "Y" connectors, any tips again with the revving?

sorry for all the questions, i just wanna make sure i get this done right...i dont wanna jack my sh*t up, hehe

 

1) Correct

2) Correct, running. On the IACV, I try to keep the rpms low, since that's where the IACV functions mostly. Ill start spraying while it's idling and as it starts to die I rev it up. I'll stop spraying till it'll idle again. Then do it over and over. An 1/8 of a can or so is quite a bit.

3) On the drivers side, the tube coming up from the Y stays and you cap it when finished. I left that tube on because the Y connector is buried under the TPS and wiring harness. On the passenger side, I just capped the Y connector. It's easily accessible. You can leave a tube on the passenger side and zip tie it somewhere if you choose.

When spraying the t/b's, you need to spray alot. I actually watch the clear plastic tube fill up with liquid. You also need to get the rpms up a bit. The intake tubes are relatively big and it takes quite a bit of spray to have an effect.

An added note.... I'm trying to get enough cleaner thru the motor to where it's actually cleaning residue off the o2's and cats.

You can also apply SeaFoam this way.

 

k thanks once again....carb cleaner is ok on a fuel injected vehicle? and what is seafoam?

 

k never mind, i did a search on the net about seafoam...now do i use the carb cleaner or the deep creep version?

 

http://www.aphrodite-z.us/techs/throttleandiacv.htm

I'll make it prettier later when I get around to putting up the rest of my site, but this way it doesnt require password to see

 

k just got all the parts...but, i got the seafoam spray instead...the guy at the advance auto store i went to owned a z too, and did this exact thing at one point...and he said the seafoam would be better. and witjh the
5/8 x 5/8 x 3/8 "t" connector, i, along with everyone else couldnt find one...so the same guy at the store told me just to get the 5/8 x 5/8 x 5/8 "T' and it will work just fine, and just get a 5/8 cap instead...

ill be doing this friday night after i get my spark plugs(since i had to order them, cause they didnt have them in stock as well) and ill definitly know how it goes and how it runs...thanks again guys