Maxima Man

Well I changed all the visible vacum lines and then fired her up and it idles rough and will sometimes bog down and the cut off!! on me

I did bump a few wires trying to install the new vacum lines but I dont think that would cause this!

BTW: The car had a smooth idle and would never die or cut of !!

I am so ticked Someone please help me figure this one out

Thanks

Greeny

iTrader: (43)

Idle air control valve...Maybe

vg or ve????

Maxima Man

Its a vg 1989 max

Greeny

iTrader: (43)

Try cleaning the throttle body and iacv....Don,t use carb. cleaner...Only Throttle body cleaner..

http://www.motorvate.ca/mvp.php/518

mattcomet82

iTrader: (6)

did you hook up some lines backwards?? forgot one hose?

seanneal

iTrader: (1)

This sounds like the most likely culprit. Here are some diagrams so you can double check everything:

alpicone

You probably mixed up a couple of vaccum hoses. So now s/t is getting vaccum when it should't be, or vica versa. Check the EGR hose. At idle it should not have vaccum. If it does then you have to figure out which one it is mixed up with.

Wiking

Both pics are for VE... still, theyre good pics. I guess u can find the VG pics also?

Your problem is what u did =hoses... maybe now a IACV hose leak?
For small hoses, click: http://www.cardomain.com/ride/748507/3

Maxima Man

I replaced all the hoses i could find but could have missed a few

I would like to get the vg engine vacum hose map if someone will please post it !

When I start the car it runs around 1000 rpms but if I rev it up the let the rpms drop they drop into the 600's Then when it strugles it goes to about 350-550 range then something must kick in and then the idle revs back up to 750-850.

What is kicking in to make the rpms jump?

When the car is running and I lean over and listen to the airbox side of the engine I can hear quite a loud air whistling noise (VACUM LEAK?) But I just changed the hoses and.......... most of them were cracked all over.

How could replacing old leaking hoses do harm to my engine ?

I dont think i could have mixed up the hoses because if memory serves me i took them off one by one!

Could my new vacum hoses be pulling a stronger vacum that now some other hose started to leak?

I really need to fix this thing because i need to drive this car!

Thanks Guys Keeep posting !!

Wiking

Link already posted. Keep reading, pls.

Dont forget to check The favorite Links.

Maxima Man

I read your link

Thanks wiki

BobbyR1972

iTrader: (2)

make sure you tighten up the clamps good.

Maxima Man

The lines i replaced were only the small lines the 5 or 6 mm lines.

There were no lines that had clamps just simple push on vacum lines.

Does any body have the vg vacum line map

I read your page wiking and the page before and after but I still need some information! Thanks wiking

Thanks guys keep posting!!

Wiking

Here is "some". And more. BUT. If u GIVE detailed req, u get detailed answer...

idle oscillation:
- IACV cleanup; detailed tHere
- TPS zero pos sw ok?; detailed tHere
- idle troubleshoot & some & all info; Favorite Links

map: each accessory is detailed separately plus semantics plus gallery pics

mooseboyd

Check the Vacuum Hoses going to the Carbon Canister. The Loud whirring sound is probably one of those lines that came loose. It happened to me and took me quite awhile to find out what it was.

Hope this helps.

Maxima Man

Is this canister under the batery in the vg engine bay?

I would like to see a vacum line map for the vg engine that way I can check all the vacum lines for leaks ! Please post the vg vacum diagram.............. Thanks so much

What is good to clean the trottle plate?
Will cleaning it strip the special oil film on the plate?
I was told it would be bad to lose this special film of oil!
Thanks so much ....Post please!

Greeny

iTrader: (43)

Go to wiking's home page for the vacuum hose diagrams..

Clean the throttle body and iacv with THROTTLE BODY CLEANER....Not carb. cleaner. There is no special oil film on the plate or anything else on the throttle body...Carburator cleaner is harsh on the aluminum....

Did you read this post and go the link???????
http://forums.maxima.org/showpost.ph...40&postcount=4

Wiking

Nope. He can only write

Maxima Man

I read your links and posts guys lot of great info!

I was just trying to clear a few more things up

Thanks Guys !!!!!!!!!!!!!!!!!!

Is there any other vg vacum line diagrams I could get or someone has?

I want to check all my lines and make sure I replaced them all !

Wikings are some what confusion lol !

Wiking

- seems u did not. If u did, take 2nd wind
- Yes, pics with txt from Maxima spaghetti & maximized confuzean FSM
- btw. FSM contains no maps, theyre for geologists. Thats why u cannot find em

Maxima Man

Ok ... This weekend I am going to clean out the ivac and the egr valve and then check for any missed vacum lines and then fire it up and see if that fixes it !

I do read your posts man! Believe me !!!

I like to learn .......

From you smart people before tearing into somthing ! LOL !



wiking= .... ..... Maxima man= .......


LOL Just Kidding....!

Greeny

iTrader: (43)

Pm me if you get stuck......

Maxima Man

10-4 I will do !

What do you recomend using to seal the ivac back up with ?

I don't have time to buy the proper gasket

Would some liquid gasket work or the like?

Thanks ........ Guys

Greeny

iTrader: (43)

I have taken both the my parts cars iacv and my daily drivers off and cleaned them and the gasket was still in good shape,so i reused them with no problems.... But if you feel the need to put something on there then i guess a paper thin layer of some rtv sealant with the old gasket still on there would be ok......

red-line-racer

iTrader: (1)

move around the fuel inject.. connectors cuz it may have a bad connection this happened to me the second inject... was lose and i moved it around and it was idling fine in no time

Maxima Man

Is there a easy way to clean the fuel injector connecter to be sure of a good contact?

Thanks guys !!

Greeny

iTrader: (43)

Get a stiff bristle tooth brush and some electrical contact cleaner....and start brushing..

Maxima Man

When I open open up the iacv is the ECU going to have to be reset or something like that?

The haynes said that the ECU would forget where the stepper motor was posistioned

Is this true ?

Or is it just if I had to disconnect it to replace the iacv with a new one

Thanks MyGreenMax !!!!!!!!!!!!

Greeny

iTrader: (43)

.......Might want to ask wiking.....

Wiking

Anybody readin hayness, willl forget where they were positioned. Get THE better manual as suggested...

No IACV reset. Idle adj as manual suggests.

In a way ECU never 'forgets': it has -and never will- know about the stepper motor, but can it ? forget smtg which it has never known, dunno

'My' stepper motors have never had zero positions so far. (Floppy disks have one zero pos sw for home, but separate from stepper...) And max is no exception, its stepper is able to run into both valve ends. U can also do that if u care to read the IACV page, or the suggested manual...

ECU energizes stepper (runs IACV back &forth) to reach the rpm = sweet idle airflow = valve pos. YOU adjust that value into ECU with ECU potentiometer. ECU pulses stepper motor back &forth until that point is reached. This continous 'search operation' is the idle fluctuation felt always in maxima.

Maxima Man

Thanks Wiking for the awsome info !

I will hack into it as soon as I can get my hands on a can of throttle body cleaner !

I have one (I promise) more question is the TPS extremly sensitive as to where it is located on the throttle body bolts? because I noticed that they have slop in them until you pick a spot and then tighten them down. ( I hope you get what I am saying )

Or is it not neccesary to remove at all?

Is it best to remove the part of the throttle body that houses the two butterfly plates
Or can you clean it just as well on the car ?

Thanks Guys props for Wiking!!!

Wiking

Info Is Good.

I'd say this forum is awesome, thks to ALL and everybody

TPS has zero pos sw, which has to open/close aroun 1000rpm. See page http://www.cardomain.com/ride/748507/6

Take TB out, in my case the last seal was misplaced causing input air choking... Removal does not add much more work there... Clamp /pinch first the TB heater hoses, then there will be no need to bleed the coolant.

When u have the plenum out, grind all extrusions left there.