1987 nissan pickup rough idle prob - Page 2

mtdss1 · Jan 24th, 2006, 06:04 AM

Quote:

Originally Posted by bkdbest

i have a 1987 nissan pickup with a z24 engine my truck was idling rough so i tuned it up replaced the oil,air.fule filters oil, spark plugs but it still was idling rough then i noticed that some of the vacume hoses had fell off so i tried to replace them but some of the hoses had fallen off and i do not know where they go i also adjusted the distributor right and left but it did not help with the rough idle it idles up high then idles down and dies

1= can anyone tell me how to hook up the vacume hoses or tell me where i can find a diagram of the vacume hoses

2= is there any way to adjust the idle

3= any help would be greatly thankful

i have done the exact same thing with my 83. i did eliminate the tvv (the thing with three vacuum hoses,<because it had broken into> some sort of heat sensor attached to it) ( on the intake) and it does seem to run better but still rough idle. if anyone finds a vacuum diagram ............ that makes sense... please e mail me too.thank you thank you!!!

pioneerscot · Jan 31st, 2006, 05:38 PM

there is usually a vacume diagram on a sticker under the hood some times its hard to see if its covered in grime

rogerd · Feb 19th, 2006, 12:45 PM

Quote:

Originally Posted by nissannut

Plug or replace the AB valve. Those fail and cause a huge vacum leak and prevent idle. I still have a spare one. You should have a Z24i since its fuel injected. Nissan never madea FSM for the 87 only the 86.5 and 88. I have an 88 it you still need it. I remember the vacum layout after owning 720s for 10 years.

I have also been looking for the vacuum diagram for 87 p/u with Z24 engine. Do you have access to one?

bkea · Mar 8th, 2006, 06:55 AM

The 87 field service manual has the vacuum diagram included in with other systems and it isn't very good. There are subtle differences in some of the trucks too. Some have the TVV valve with two hoses and others have a diiferent kind with three hoses. Some also have an EGR solenoid, but mine doesn't. Boy do I wish someone would draw it out and post it for posterity.

BTW, my 1986.5 Z-24i does have a five branched gismo on the air cleaner. There is a sticker right next to it, but the hoses are labeled with colors, and guess what. The hoses have been changed and there's no colors on them now.

lilFlip · Nov 8th, 2006, 06:36 PM

ok, I know that this thread is pretty old...but I just found this forum and am having similar issues did anyone find the vacuum diagram?

nissannut · Nov 8th, 2006, 07:16 PM

Quote:

Originally Posted by lilFlip

ok, I know that this thread is pretty old...but I just found this forum and am having similar issues did anyone find the vacuum diagram?

I have an 88 and a 86diagram. The vacumn is almost identical on the z24s.

Let me try to scan it for You.

You may want to try nissanofforad.net while you wait. or 4x4parts.com. There bigger Nissan forums.

lilFlip · Nov 9th, 2006, 12:50 PM

Thank you nissannut...also, I'm trying to locate the idle switch...any idea on this? I'm getting the code 23 on my ecu...

Do you get different codes flashing when the engine is running and not running?

nissannut · Nov 9th, 2006, 12:56 PM

Quote:

Originally Posted by lilFlip

Thank you nissannut...also, I'm trying to locate the idle switch...any idea on this? I'm getting the code 23 on my ecu...

Do you get different codes flashing when the engine is running and not running?

Having trouble getting my scanner working. Apparently my 20' usb cable went bad. I can scan now.

The idle switch is in the TPS (throttle position switch). If I remember correctly. Thats on the head side of the tbi.

lilFlip · Nov 9th, 2006, 01:26 PM

ok, when you can scan it, can you send it to me anyway? Thanks for the information. I think I need to go get a throttle position switch and see if that corrects the error code and then move from there, but I would like to double check the vacuum hoses as well...as I think that is another issue.

nissannut · Nov 9th, 2006, 01:38 PM

I put a link to a big jpg on the z24i conversion page. Nissan Nut
Some other pix on that page may help you.

Make sure you open in mspaint or something. It will not be blurry. If opened in IE its all blurred. Since its a big page scan.

code 23 is not in the 88 book. I just remembered the tps is on the firewall side near the linkage. It is adjustable. Airflow is on the head side.

here is the direct link. http://nissannut.com/projects/z24i_f...acumn_z24i.JPG

lilFlip · Nov 9th, 2006, 03:57 PM

NissanNut,

I have another question for you. Do you have any other diagrams that might help me map the following correctly? It may be in the diagram you posted, but I'm having a hard time mapping them together...

Also, is there a way to test the Throttle Position Sensor, before I drop $110 on a new one?

nissannut · Nov 9th, 2006, 04:47 PM

That thing is just a T and a pass through. There is 5 connectors. Originally the hoses were all color coded. But that wears off.

There is a two port manifold on the intake right in front of the tbi.

There is a vacum source on the tbi. I just noticed the evap is not mentioned in that pic. I have another page of JUST the evap circuits.

I just marked up that same jpg with colors. Should make more sense now. I fixed ALLOT of friends z series motors. They run bad when hooked up wrong. This chart is the same for z20, z22 and z24 and z24i.

lilFlip · Nov 9th, 2006, 06:11 PM

Thanks a lot for the information and going out of your way to help me out. I will check these out now that I know where they are suppossed to go!

500tim500 · Apr 25th, 2007, 12:30 PM

I am having the same problem, except my will not kill all the time, it just idles up and then way down low, it will kill when placed in drive or reverse (Sometimes). It will drive fine unless you punch it then it runs like crap, missing backfiring, sounds like its only hitting on 2 of the 4. I had it in last week and there was a corroded wire that lead to the injectors which allowed it to not even start. $160 later it now runs but with the above mentioned problem. any help would be good.

nissannut · Apr 25th, 2007, 12:48 PM

Quote:

Originally Posted by 500tim500

I am having the same problem, except my will not kill all the time, it just idles up and then way down low, it will kill when placed in drive or reverse (Sometimes). It will drive fine unless you punch it then it runs like crap, missing backfiring, sounds like its only hitting on 2 of the 4. I had it in last week and there was a corroded wire that lead to the injectors which allowed it to not even start. $160 later it now runs but with the above mentioned problem. any help would be good.

Have you tried the basics?

Check or replace cap/rotor, plugs, plug wires etc???

Yours sounds pretty serious. Do a compression test also.