replacing IAC question

[Chriskaw440]

I wish I had just replaced it when I did my knock sensor.....since I had the plenum removed.

 

Now its acting up worse so I just want to replace the Idle air control valve but I am hoping I dont have to completely remove the plenum...again.

Mostly because of the two coolant lines at the very back of the plenum that are such a pain in the a** to reconnect.

 

can the plenum just be unbolted / lifted for enough space to work with to replace the IAC? since it is located on the underside of the plenum.

 

(1990 SE)

 

Since its the original IAC (far as I have ever known) I don't want to bother trying to clean it....just replace it with a new one and be good to go.

 

My idle keeps getting stuck at almost 2,000 rpm most all the time now instead of only on occasion.....everything else checks out ok and its fully tuned.

 

thanks, Chris

[Indigent]

I spent more time trying to figure out a way to get to that valve without removing the plenum than I would have if I had just taken that stupid thing off. I actually made more work for myself, because I attempted to just lift it up an not disconnect the coolant lines. Turns out that all of the wiggling I did cut one of the coolant lines pretty bad, and I had no idea. I was driving home from work and my engine started to overheat. I had lost all of my coolant through that line.

 

Once you have taken that plenum off, it gets easier, I promise. Its only a couple bolts and those two little coolant lines. I have never had to use a new gasket either. I have been lucky that it stays intact, but YMMV.

 

hope this helps.

 

indigent.

[Alkorahil]

Getting it off is the hardest part. Putting it back on took me about half the time.

[Chriskaw440]

Thanks guys.

 

Yeah since I replaced those two stupid lines when I did my knock sensor, you cant find factory-pre-molded hoses anymore (of course) so I had to use regular hoses and try to get them to bend just right without kinking and use band-clamps instead of the useless original equipment clamps (that you remove or install with pliers) cause they couldnt clamp strong enough without leaking.....and we all know that unless you have itsy bitsy sized hands, there is very little room to work with back there......but, I did learn to go buy two kinds of needle nose pliers to make the job a bit easier.....LONG handled and LONG nose style pliers, one with the 90 deg angle on the nose, and one with a 45 deg angle.....GREAT for reaching into those hard to get to areas for things like clamps or hoses.

 

guess I will have to suck it up, have a few drinks to calm my nerves, and just take the whole plenum off again and then get my buddy back over to help reinstall it and connect those friggin stupid coolant lines...

 

I still curse Nissan engineers for putting the IAC valve in such a dumbass place.

 

I still love my pathy

[Indigent]

One more bit of advice:

Replace those two little hoses with much longer ones (like 4-5"). Loop them around in a circle so they don't kink. Then the next time you have to get the plenum off, you will be able to lift it up and get to the hoses from an easier place, and maybe not have to remove them at all. Even if you only have to get it off one more time, it will make your life easier.

 

Hope this helps.

 

indigent.

[Alkorahil]

Thanks guys.

 

Yeah since I replaced those two stupid lines when I did my knock sensor, you cant find factory-pre-molded hoses anymore (of course) so I had to use regular hoses and try to get them to bend just right without kinking and use band-clamps instead of the useless original equipment clamps (that you remove or install with pliers) cause they couldnt clamp strong enough without leaking.....and we all know that unless you have itsy bitsy sized hands, there is very little room to work with back there......but, I did learn to go buy two kinds of needle nose pliers to make the job a bit easier.....LONG handled and LONG nose style pliers, one with the 90 deg angle on the nose, and one with a 45 deg angle.....GREAT for reaching into those hard to get to areas for things like clamps or hoses.

 

guess I will have to suck it up, have a few drinks to calm my nerves, and just take the whole plenum off again and then get my buddy back over to help reinstall it and connect those friggin stupid coolant lines...

 

I still curse Nissan engineers for putting the IAC valve in such a dumbass place.

 

I still love my pathy

 

 

 

1) exactly which hoses were you wanting?

 

2) agreed on the engineers!

 

3) agreed, stil love my truck.

 

4) try replacing the rear spark plugs on a Murano!! (step 1: drop engine)

[Chriskaw440]

1) exactly which hoses were you wanting?

 

2) agreed on the engineers!

 

3) agreed, stil love my truck.

 

4) try replacing the rear spark plugs on a Murano!! (step 1: drop engine)

 

The two small diameter (about the same as fuel line hose) coolant hoses that attach at the rear underside of the plenum (there are coolant lines on the bottom of the plenum....) Originally they are pre-molded at about 90 deg angles....so replacing them with standard straight hose that you have to bend so much usually results in a kink...and I couldnt find any of those anti-kink 'springs' or whatever they are called for hose that small....but I did manage to make them fit eventually without a bad kink.

 

Yeah engineers need to pay more attention to ENGINE COMPARTMENT ACCESS ROOM to the commonly replaced parts instead of how fancy the stupid cup holders are on the interior or an extra two inches of leg room. Todays new cars have vast amounts of space on the inside (oh whoopie do unless you weigh 400 lbs or have a Brady Bunch sized family) and removed ANY access space under the hood so even the Nissan mechanics probably say to themselves "Oh sh*t, here comes another Murano for a friggin tune up....damn."

 

thats just plain incredibly STUPID to have to lower or raise the entire engine just to get to ONE or a couple of the spark plugs. I know this is the case on other vehicles too but you would think that for it to be that much work just to change a spark plug....engineers would realize that "hey...this is stupid....there must be a better way around this"....I mean come on, they are ENGINEERS afterall....supposedly about the smartest people on the planet!

 

If I was buying a new car and asked "can I change the spark plugs and oil filter myself? and they said "no, that requires our specialist/technicians...you'll have to make an appointment and plan to leave the vehicle with us for a few days because we have to actually partially remove the engine for the most part" I'd say fine, show me a car/truck/whatever that is NOT like that please.

 

This is why I like older vehicles better! Besides, by the time they perfect an alternative energy vehicles and make the gas powered reciprocating engine obsolete....I'll be dead of old age anyway.

[Alkorahil]

The two small diameter (about the same as fuel line hose) coolant hoses that attach at the rear underside of the plenum (there are coolant lines on the bottom of the plenum....) Originally they are pre-molded at about 90 deg angles....so replacing them with standard straight hose that you have to bend so much usually results in a kink...and I couldnt find any of those anti-kink 'springs' or whatever they are called for hose that small....but I did manage to make them fit eventually without a bad kink.

 

 

Sounds like on of the three highlighted here, let me know. I have one of them in stock, cant check availability till Monday on the rest.

[Chriskaw440]

Yeah those two highlighted in green look about right....they connect to the inlet and outlet heater hose lines for the most part I do believe.

 

Hey I see the EGR hose on there shown at the bottom right ....(thought it goes to the PCV also....I could be wrong) and I couldnt replace mine at the time and I could use that one also if you have it.

 

I think I will take a digital cam shot of my plenum and point out the premolded hoses I have trouble finding.

 

thanks for the help!

 

-Chris