Bags

iTrader: (3)

I STILL have the DAMN vaccum leak. I hear it around the roear PASSENGER side of the motor. I am thinking it is from the valve cover gasket. Any thoughts would help there.


Now on driving with a vaccum leak.

I am at about 10HG or so. Is this harmful? Not boosting and staying under 50 MPH will I hurt anything driving for a few days like this? Short trips under 15 miles.

the biggest thing is I loose power brakes at 10 mph or slower sometimes. I was working that out last night.

I want to find and fix the leak, but I NEED to have my car.

Thoughts?


Thanks

DA-MAX

iTrader: (10)

not sure how relevant this is, but based on the brake situation does the Maxima use a one way valve on the brake booster line?? (it'll look lke a clear disk, maybe .25-.5" thick, inline on the booster hose)

Jeff92se

iTrader: (82)

Good call. I'd also triple check all the vacuum lines leading to the brake booster. Even with low vaccuum, you shouldn't loose the brakes. I'd try to take a look a the brake boost too. Maybe it's bleeding off vacuum. Especially if it can't store enough vacuum to assist the brakes.

Bags

iTrader: (3)

it comes and goes.

But I will check that out

Tahnks jeff and da-max

RS Motorsports

iTrader: (3)

Hey baggs i was having the same issue as you are having and am trying to work everything out right now. I have had a bad vacuum leak for a while know and just recently if it dropped bellow 10 hg and at slow speeds the brakes would just not work. Pfi is trying to fin my leak right now so we'll see if it solves the problem.
Ryan

Bags

iTrader: (3)

Do you have a MEVI?

If so check ALL of it. I'll post pics later of what I am talking about

ejj

iTrader: (5)

I drove with a leak for quite a while. I was missing my EGR gasket, because I forgot to put it on the USIM after I blew my engine with the MEVI.

The car stalled all the time when slowing from speed (25mph+). I would normally just pop the clutch and "push start" it.

I _never_ had probelms with my brakes though.

|Bijan|

iTrader: (12)

I really hope once the stock manifold is back on....it can run fine.

stephenlc

iTrader: (1)

Ahh, I am having so much trouble with my vacuum leak. My car starts for like a second then it dies. I hear the air gush out and there is a slight smell of gas. I get to take my manifolds off clean and sand all the places were gaskets are and see if the old gaskets work. If not I get to go spend 100 dollars on gaskets, ya!

DA-MAX

iTrader: (10)

have you recently messed with the FPR??

RS Motorsports

iTrader: (3)

ya i have a mevi but i took it off and put the usim back on and i still have a bad leak so im gonna have to go through everything to find out where it is coming from.
Ryan

stephenlc

iTrader: (1)

Ya I fixed mine! Now I have a cut coolant line somewhere behind the intake manifold. Also need to get throttlebody gasket, it sounds like I have a turbo. It only took me two hours to clean all gaskets, flanges, take top and bottom manifolds off and put them back on.

bobjohnson

iTrader: (2)

I FINALLY FIXED MY Vacume Leak as well

Same Spot. Passenger SIDE.

What you are looking for is the METAL HOSE which connects to the BACK of the Engine. You CANNOT see it, you have to feal under the manifold, against the Firewall of the car.
This Metal Will have a Nut on it & a Plate which Connects to the Back OF THE Engine.

It Took 3 Dealer Analysis,& 1 Specialist. Then I was Broke and Disassembled the Entire top of the Engine one Night and found this Loose Pipe.

THIS NEEDS TO BE A STICKY*
May of us spend countless & extensive money to TRY and find this Vacume Leak. Im glad we've found the problem.

Bags

iTrader: (3)

Metal hose?

passenger side?

Mine was the valve cover gasket. I could feel it leaking. I fixed that and still have a vaccum leak.

Where abouts on the engine?

From what your saying it sounds like the power steering lines

bobjohnson

iTrader: (2)

No This Metal Line I was referring to Was Actually the Fix of All My Vacue Leaks AND EVAP Canister Purge Valve Control Valve Seloniod.

I Had Every Evap Code and a Vacume Leak.
THis Metal Vacume Part actually connects from the back of the engine to the egr Metal pipes and those controls. I was Cleaning all of my EVAP parts again and again, then i found where the EVAP and EGR all Flow together to make Everything work.

Sometimes its not what the ECU tells you. Its why it's telling you that and backtracking the problem i guess. It took me 1yr/20,000 to finally find this problem. It runs like new IMO...

stephenlc

iTrader: (1)

Have you tried that orange thing that connects to the back of the manifold on the right side of the manifold. You can have a bad leak if you lose the gasket for that.

iansw

iTrader: (7)

The EGR has nothing to do with the Driver's side of the car, nor does the EVAP.

The only EGR hose connecting to the back of the engiine is the EGR coming up from the Headers, and is on the driver's side.

So I'm dying to know what you're tlaking aobut, because I'm getting the EVAP Solenoid code, even though my vacuum is reading within spec.

So what are you talking about!? There are no heses/pipes of any kind on the passenger rear side of my engine....except the A/C Piping going back.

bobjohnson

iTrader: (2)

It is for my 95-96 Maxima.
97-99 have EVAP controls near the Rear tires. Your 97 should have EGR under the Hood on the Driver side insaw.
______

It's Not On the Passenger SIde. Look at the IAC or TB.

Now under this on MY 95 is the Evap Canister, then rubber to metal hose to seloniod valve & another that goes under the TB.

Near the Firewall right here is the EGR and all the Associated Parts. As you will see the metal pipes here are all closely either going into the Back of the Engine Block (Part that was lose on mine) or they will go to the Other EGR Control units.

I was getting MANY EGR & EVAP Code. Left and Right... a new each day for 2 weeks..

Look for this metal tube near the firewall , its kinda brass but check the plate which connects IT to the back of the engine Block..<- Hense = Losing power / stalling under fast stops OR RPM's Falling Off and Stallin...

These ALL were the most common. I Replace Nothing when I got all 10 or so EGR and EVAP codes. I cleaned $hit and Found this Loose Pipe eventually.. Just feal back near the fire wall, see if its loose ,Its near the Top.

Any more questions,

iansw

iTrader: (7)

So are you tlaking about the pipe and gasket in the following pic (highlighted red & green)



Or do you mean the brass vacuum lines that go to the EGR, FPR, etc, etc?

bobjohnson

iTrader: (2)

Yes Yes! Thats the Piece (red and green). see that Brass pipe . Mine was Loose from the start so it was a small siiiiiiiiii blowing off.
But by 6 months it just got worse and worse. Or loose and loose from the back of the engine..

i did fup my first post by saying passenger side. But the pipe is in the Middle of the Block and just took for ever to figure out.

go tighten it up. i used the nissan oem gasket sealer to make sure it was a tight fit. good enough i think.

Bags

iTrader: (3)

Ok that is the EGR, Exhaust Gas Regualtor valve, is it directly related to vaccum.

If it is clogged or is the gasket is not on correctly vaccum will be low.

Did you tighten it up at the back of the intake manifold or the exhaust manifold?

THANKS IAN for the pic

Also item 1471 and I think 14710 are the diapharms that help create vaccum. i am leaning towards those

iansw

iTrader: (7)

That is the EGR Return Tube and Tube Gasket.

That's exactly what I was telling you to replace baggs over AIM.

Unfortunately, that's not my problem, since there is a brand new gasket on there for me and I've re-checked the torque on it a couple of times.

No biggie however - I'll be replacing my manifold again with another new bored out MEVI in a few weeks.



IanS

Bags

iTrader: (3)

I am looking at the tube it self. I knwo for a fact the gasket is new and good. I have insatlled it and removed it several times and I can't feel any leaks back there with it on. I did it once with it off and I did feel a leak.

I put a LARGE crack in my manifold, becareful in removal and installtion.

How hard is the tube to remove? With the engine installed

Thanks ian

And please feel free to email or aim me the info about the bored one. Curious as to the sizes of the new holes. Also did you desktop dyno it?

iansw

iTrader: (7)

I don't desktop Dyno - I'm all about the track.

Anyway - that tube is a total bish to remove/replace. If it's got the gasket, then that's probably OK.

If you put a crack in your manifold, then that is your problem if air is escaping from that crack.

Also, did you replace your Throttle Body Gasket?

Bags

iTrader: (3)

Well I put the US manifold back on and fixed a leak I had on the valve cover.

I did not replace the TB gasket. But I am seeing 4-8 HG of vaccum when it should be ~18 HG.

That is why I am leaning towards the diaphram's.

I have been chasing this and a MAF problem for ~4 weeks now. I can't drive the car due to the lack of power brakes

I am unhooking the brake vaccum line tomorrow and pluging that to see if that fixes anything.

If I knew of a place to take it and do that "smoke" test you did I would.

I am also doing a compression test tomorrow finally as well

And yeah I thought that tube would suck..lol.. I have shot a good amount of carb cleaner down it when it was sitting on the motor stand, so I don't think it is clogged.

iansw

iTrader: (7)

It's the TB gasket.

Bags

iTrader: (3)

I can't feel ANY leaks there.

If I change it and it does not help can I you ?

iansw

iTrader: (7)

I couldn't feel any leaks there either when the exact same hting happened on mrb23's car.

It's this easy:
The manifold has 4 points that air must be 100% sealed on.

1) The EGR Tube
2) The IACV Valve
3) Throttle Body Gasket
4) Connection from manifold to engine

Since this all started when you took your manifold off and put it back on, I'm sure it's one of those things. #4 should be obvious, #1 you already checked, #2 is unlikely. So i'm sure it's #3.

Could also be a loose hose, but you don't usually lose that much vacuum with just 1 vacuum hose disattached. So I'm betting it's the manifold.

iansw

iTrader: (7)

As a matter of fact - before you do anything else, mix a spray bottle with 1/4 soap and 3/4 water and spray your engine bay down, then rev the engine while doing it.

You'll see the soap being sucked in when at idle, and then bubble like crazy (it should be very obvious) when revving.

That's how I found my compressor leak. The smoke machine actually didn't find that because it was so far down the intake piping.

IanS

bobjohnson

iTrader: (2)

Woah woah soap & water mix????

The only way i ever found my EGR leak was by spraying a Carb Cleaner around back there in little amounts. That way you can focus on each section of it off while u spray in the cracks on the line and around it. -i imagine you heard how the engine will revv when u find the spot.
This Should work to Locate 'Around' where the problem is.
The Soap will leave a resude. Carb Cleaner will Dry up Quickly.
Now Gaskets... eh Ive removed the Entire top intake Manifold / TB/ IACV all those. I never Once replaced 1 gasket. Not 1. I did tighten everything in sequence though... u know what i mean.

bags533> Right, thats why i was getting EGR codes. I tightened it on the top part. The 'red' pic is the exact part i was never seeing. The 'green' pic of the gasket is right where i tightened it up at.

iansw

iTrader: (7)

Soap and Water works far better.

And if you use Dove dishwashing soap - It leaves no residue.

And any residue it may leave gets burned off when the engine heats up. It's a old and proven trick. Just as old if not older than carb cleaner.

When I had my leak I tried 3 bottles of carb cleaner before trying the soap trick. The Carb cleaner helped me find 1 leak, but not exactly where it was.

It only let me know there was a leak SOMEWHERE near the back of the manifold. The soap would have located it perfectly. (I did find it using the Smoke-It thing, but baggs apparently has no access to one).

Although Carb Cleaner should help in this case at least find the general area.

So edit my previous post baggs - try some carb cleaner THEN Soap & Water to nail it down.

IanS

Prodeje79

Wow this seems to be a really useful thread. I am going to try looking into the advised issues.

Since my original install, we have been seeing -10 to -11 psi at idle on the PROfec E-01.

What is ideal boost/vaccuum reading at idle?

I had my tranny repaired this past week. I immediatley noticed when I pcked up my car that the boost/vaccuum was reading 0. Upon further inspection, the boost sensor metal nipple did not have a rubber hose attached.

We followed every rubber hose, from FPR, BOV, wastegate, FMU, etc. We cannot find a stray hose.

As a temporary workaround, I bought another T and we split it onto the boost sensor so we could see something at least.

We really here a hissing sound coming from near/under the TB.
I really want to check all the things metioned in this thread and will.

I am also open to more ideas if there are any.

Does anyone have a general listing of all what and where the vac lines should be connected ideally? I do have a MEVI if this changes things.

slimer

iTrader: (13)

there is a vacuum hose underneath the tb. it is vertical. Vacuum should be 15-19 in/hg

cardana24

iTrader: (81)

an easy way to find a leak is to use a small bottle of propane (camping size) and spray it on suspect areas....if any propane is taken into the intake trac, it will make the engine speed bump up real quick.

Prodeje79

My profec only reads around -5 or -6 at idle now.

My brakes are working OK though.

I am afraid to boost though. I am afraid the FMU would not be bumping up enough fuel due to the low psi.