'90 300ZX N/A "quirks"

[Nore]

Hey everyone, First I would like to thank all the posters that make so much of the 300Z info easily available. I am currently waiting to get my 1 piece driveshaft in to replace parts that use to be called a stock driveshaft.

After going all over the engine trying to find where the gas smell is coming from I have found that most of the vacuum lines are old and degraded, not hooked up, or in poor condition. Im probably going to just redo all the vacuum lines while waiting for the driveshaft.

Even better are two lines coming up from the passenger side near the battery, I have no idea where these go.

Two hoses to where? From where? Hmmm....Here is where they go in, possible they arent vacuum hoses

So, after repairing the driveshaft, I need to take care of what looks to be a leak in the oil pan This I may just take somewhere and let them pull the crossmember and all the hard work involved at getting this fixed.

Oil on pan just behind Crankshaft Pully

I went through the ModeII diagnostics (not the full O2 Sensor, just code readout) and came up with 13 and 53. Since the engine light isnt on during normal ModeI Im pretty sure they where fixed, I have two Exhaust sensors in the back and the clip for the Temp Sensor isnt very strong.

After these majors are done and the car is in good mechanical driving condition, I will turn my sights to fixing the interior. Z32's are just so damn pretty combined with RWD awsomeness, how could a person not fall in love?

So, main questions, Anyone have suggested mechanics in Southern California (Bellflower/Long Beach area) to do the leaking oil pan? Anyone know what those two hoses near the battery are for? Should I clear the ECU of errors now?

Thank you =)

[Zwicked]

With this engine, you need to ensure everything is initially right so you have a solid base line to start from.Unhook your battery over night and then check for codes again. If they are still there, they need to be attended to. Also do a diagnostic on the o2 sensors to ensure they are up to par.Aside from failed components, the most common cause of issues on the Z32 is intake piping leaks and corroded connectors.Changing all the hoses is a good idea if they are cracked or hardened from time. If you have a POP intake, you'd be best pressurizing the system (no more than 5 psi) to help you find all the leaks. Any air getting in from other than the air filter is unmetered air and the ECU just can't account for that so the engine won't run right.Also, remove every connector with that wire clip (CAS, PTU, MAS, injectors, Coolant Temp and Fuel Temp sensors, AAC, IACV, Aux. Air Valve) and make sure they are 100% clean. While you have the injector connectors off, test with an ohm meter to see if they are in spec (10 ~ 14 ohms).Investing some time on the fundamentals is time well spent to eliminate any possible gremlins

[Nore]

The car runs decent, seems to have plenty of power. Ill follow up on clearing the codes and checking again this weekend, which Ill probably run the O2 sensor test as well.

Ill follow the suggestion with the intake pipes, I know so far both Exhaust sensors and one injector have been replaced. Belts look like they where recently replaced, Ill have to take the covers off and check the timing belt though.

Is there an easy way to replace the temp. sensor connector? It may cause problems later on being as lose as it is, so it may be worth just replacing it now.

[freakonaleash1187]

1) That vacuum hose next to your battery, I have never seen that before.

2) The sludge on your oil pan is most likely due to a leaky front main seal.

[Zwicked]

Cut and splice is about the only way to replace the connector that I know of. The coolant one is critical and needs to make a good connection.

[mike_latorrelovesnissan]

Zwicked, what do you mean by pressurizing the system? I know I have a few leaks in the hoses on my Z so im in the process of changing the hoses as well. I just bought my Z like two weeks ago and im a bit of a newb lol so far Ive been trying to find the leaks by just taking each line out one at a time and checking it for leaks. iS there an easier way to find the leaks?

[Nore]

Two hoses to where? From where? Hmmm....Here is where they go in, possible they arent vacuum hoses

After looking at all the vacuum lines and where everything runs it appears that the AIV control valves are hidden in the body looking at The Service Manual Page I know where the T-splitter is, and the side running to the drivers side is still attached, it runs across the engine bay and goes into the body as well.

So, is there a way to tell which of these two hoses is for the Right AIV Control Valve, or am I going to be removing bodywork to find out where the rogue line runs too?Also, is this the Front Seal you mentioned checking? as it says to drop the oil pan still.

PS - Got my 1 Piece Driveshaft
Modified by Nore at 5:53 AM 7/13/2007

[Zwicked]

Do you have an aftermarket air intake filter, or still the stock airbox? If it's already converted to an aftermarket cone filter, the job is simple.

The easiest way to find an intake leak is buy a 3" PVC plumbing plug, grind the threads off it so it's smooth, drill a hole in the outer end and thread an air line fitting and gauge into it.Install that into the intake plastic pipe where it joins the air filter. Connect air to it BUT BE CAREFUL not to pressurize it more than 5 pounds or you can damage seals, more like 3 psi or so.In a quiet area you can hear if it is leaking. If you shut the air source off, it should bleed down real slowly if the system is leak-free.

The AIV system (and others) can easily and safely be deleted from the system (in my opinion a preferable idea). Read this if you are going to delete it, or so you know how it should be to start with:http://www.twinturbo.net/net/v...31202

*Aside from a failed component, vac/boost leaks and corroded connections are the foremost reason for the VG engine running poorly
Modified by Zwicked at 3:16 PM 7/13/2007

[Nore]

So, Ive got the driveshaft installed, am going to disconnect the battery and let it clear it tonight.

I have noticed that Im running rich, could this have anything to do with the vacuum lines not being hooked up correctly? I have the vacuum line coming off the top of the AIV Control Solenoid going to the Balance Tube like it shows in the diagram on EF & EC-11 of the FSM. Though looking at the page to Remove the AIV System it shows the top vacuum line going to the ERG Control.

I have to do smog check to transfer the title this week and if its running rich its likely to fail and cost even more to retest, so just trying to iron this out.

NOTE: I still havent done O2 Sensor test and I dont see any gas leaks in the gas lines.

[mike_latorrelovesnissan]

Thanks for that link Zwicked, its really helpful. I am deffinitely going to remove the Air induction either tomorrow or the next day. You said that there are other things that can be removed. Could you tell me what, and do you have links to those as well? Thanks alot.

[Nore]

Looking at the Emissions chart, the AIV just dumps fresh air in front of the Cat, isnt it kind of important to have that function to reduce emissions?