how to find a vacmn leak?
Thread Starter
Joined: Apr 2004
Posts: 1,378
Likes: 14
From: Atlanta, GA Ft. Walton Beach, FL
how to find a vacmn leak? I think I have a vacumn leak will a vacunm leak tester I've sean at auto stores show exact leak maybe w/ die like they check AC sys.?
or will it just say yes or no there's a leak?
Thanks
or will it just say yes or no there's a leak?
Thanks
is your idle rough? i use the old method of using some MAF sensor spray since it wont bother the electronics like carb cleaner and just give a little spray til the idle smooths out. when it smooths you found your leak. not high tech but its always worked for me
Thread Starter
Joined: Apr 2004
Posts: 1,378
Likes: 14
From: Atlanta, GA Ft. Walton Beach, FL
finding leak the idle is smooth car runs great. so I'm assumming this is a slite leak and this metod maynot detect leak.
execpt that peskie check engine light comes on and off ever sence that FAST intake swap.
maybe I should move this other thread I have
have I maxed out my 26LB fuel injectors?
to this section.
Thanks
execpt that peskie check engine light comes on and off ever sence that FAST intake swap.
maybe I should move this other thread I have
have I maxed out my 26LB fuel injectors?
to this section.
Thanks
check the map sensor in the back of the manifold...they tend to sit loosely on the FASTs...if its a boosted engine use a small ring of silicone around the base of the sensor to seal it...make sure not to not get any silicone in the pressure port of the sensor.
are you throwing a p0106?
are you throwing a p0106?
Thread Starter
Joined: Apr 2004
Posts: 1,378
Likes: 14
From: Atlanta, GA Ft. Walton Beach, FL
Fast yes I used 8 brand new FAST gaskets & the FAST TB gasket.
when I installed the FAST I did observe the MAP sesor to be loose so I used a thin layer of red silicon gasket maker.
when I installed the FAST I broke the vacumn tube that connects to rear of both cylinder heads and Ys off to the PCV.
I broke it at the pass. side head tryed to fix w/ a larger piece of heat tubing & barbed fitting used 2 hose clamps if was diffuacult to tighten because there's not much room in there.
here's the other thread I have
https://ls1tech.com/forums/fueling-i...injectors.html
since I've added a little high quailty telecom tape and retightened the repair, I cruised around today and hammered it more than a few times about 50 miles and the check engine light has not come back on.
think I'll drive it a few hundred more miles hopefully the light will not come back on then have it rescanned w/ the tech 2 tester hopefully it won't be lean on banks 1 &2 and have no high idle errors.
The high idle blows my mine because it's set low at 590RPM
Thanks guy's for helpfull advice
when I installed the FAST I did observe the MAP sesor to be loose so I used a thin layer of red silicon gasket maker.
when I installed the FAST I broke the vacumn tube that connects to rear of both cylinder heads and Ys off to the PCV.
I broke it at the pass. side head tryed to fix w/ a larger piece of heat tubing & barbed fitting used 2 hose clamps if was diffuacult to tighten because there's not much room in there.
here's the other thread I have
https://ls1tech.com/forums/fueling-i...injectors.html
since I've added a little high quailty telecom tape and retightened the repair, I cruised around today and hammered it more than a few times about 50 miles and the check engine light has not come back on.
think I'll drive it a few hundred more miles hopefully the light will not come back on then have it rescanned w/ the tech 2 tester hopefully it won't be lean on banks 1 &2 and have no high idle errors.
The high idle blows my mine because it's set low at 590RPM
Thanks guy's for helpfull advice
Thread Starter
Joined: Apr 2004
Posts: 1,378
Likes: 14
From: Atlanta, GA Ft. Walton Beach, FL
vacumn guage I have a vacumn guage off of my turbo car.
any recommendations on where to splice into to monitor vacumn preasure.
I was thinking of going though the pass. side firewall under computer.
if I have sealed up the leak w/ second repair job then the guage will have steadie reading at idle right?
or if there is still a slite leak the reading would be not constant it would fluctuate right?
Thanks
any recommendations on where to splice into to monitor vacumn preasure.
I was thinking of going though the pass. side firewall under computer.
if I have sealed up the leak w/ second repair job then the guage will have steadie reading at idle right?
or if there is still a slite leak the reading would be not constant it would fluctuate right?
Thanks
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Might sound like overkill but if you know the suspected leak area, I'd take the intake off, tape it all up, apply a very low pressure to it and us a bubble type soap leak detector and fix that leak you were talking about a little more permanent so you don't have to worry about again.
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Verdad Gallardo Thread Starter
Joined: Apr 2004
Posts: 1,378
Likes: 14
From: Atlanta, GA Ft. Walton Beach, FL
leak check the map sensor in the back of the manifold...they tend to sit loosely on the FASTs...if its a boosted engine use a small ring of silicone around the base of the sensor to seal it...make sure not to not get any silicone in the pressure port of the sensor.
are you throwing a p0106?
are you throwing a p0106?
?1. will a vacmn leak cause intermitant check engine light? or if it's still leaking should'nt the check engine light just stay on?
?2. will the manifold have to be removed to reglue the MAP sensor & that red silicone gasket maker I used may have gotten hard should I reglue with some other type glue? if so what type?
the code is P0300
Thanks
depends on the leak really...sometimes the leak wont be constant...may only appear when the engine is reved or vibrating, which is common with the fast MAP ports...
if it does have an intermittent leak, it can also have an intermittent ses light when the leak is detected by the pcm and it will set itself off when it has gone through enough cycles without an error...
the manifold doesnt necessarily have to be removed to get to it, but it makes it easier, since the fbody cowl protrudes so far out...black or grey silicone has always worked well for me...just makes sure after you put sealant on the sensor, to let it dry before you put it back on the car...also make sure you dont break the seal when you are clicking the map sensor plug back in...
p0300 is a misfire code, nthing to do directly with a manifold leak...
do you have access to a daignostic scan tool or a tech2?
if it does have an intermittent leak, it can also have an intermittent ses light when the leak is detected by the pcm and it will set itself off when it has gone through enough cycles without an error...
the manifold doesnt necessarily have to be removed to get to it, but it makes it easier, since the fbody cowl protrudes so far out...black or grey silicone has always worked well for me...just makes sure after you put sealant on the sensor, to let it dry before you put it back on the car...also make sure you dont break the seal when you are clicking the map sensor plug back in...
p0300 is a misfire code, nthing to do directly with a manifold leak...
do you have access to a daignostic scan tool or a tech2?
Thread Starter
Joined: Apr 2004
Posts: 1,378
Likes: 14
From: Atlanta, GA Ft. Walton Beach, FL
tech2 depends on the leak really...sometimes the leak wont be constant...may only appear when the engine is reved or vibrating, which is common with the fast MAP ports...
if it does have an intermittent leak, it can also have an intermittent ses light when the leak is detected by the pcm and it will set itself off when it has gone through enough cycles without an error...
the manifold doesnt necessarily have to be removed to get to it, but it makes it easier, since the fbody cowl protrudes so far out...black or grey silicone has always worked well for me...just makes sure after you put sealant on the sensor, to let it dry before you put it back on the car...also make sure you dont break the seal when you are clicking the map sensor plug back in...
p0300 is a misfire code, nthing to do directly with a manifold leak...
do you have access to a daignostic scan tool or a tech2?
if it does have an intermittent leak, it can also have an intermittent ses light when the leak is detected by the pcm and it will set itself off when it has gone through enough cycles without an error...
the manifold doesnt necessarily have to be removed to get to it, but it makes it easier, since the fbody cowl protrudes so far out...black or grey silicone has always worked well for me...just makes sure after you put sealant on the sensor, to let it dry before you put it back on the car...also make sure you dont break the seal when you are clicking the map sensor plug back in...
p0300 is a misfire code, nthing to do directly with a manifold leak...
do you have access to a daignostic scan tool or a tech2?
I thought the tech2 would tell exactly what's causeing the problem?
after I repaired the tubing and ses light came back I scanned it w/ the el cheapo scanner at autozone it read P0300 multiable misfires, low or high fuel preasure, bad injector, bad spark plug or coil plus vacumn leak.
I did a good job w/ the repairing of tubing if it where still leaking it must be at the MAP sensor or are there other vacumn tubes besides the brake booster?
I've had this manifold on for over 2 years and have allways had this intermitant ses light I'm thinking it's dirty injectors because when I treat the fuel w/ either Lucas or seafoam the light go'es off.
? how often should the injectors be either changed or professionally cleaned
I'm considering the GM top end cleaning where they connect directly to the fuel line I have never had this done just seafoam ever third oil change going though the boost tube I've never seam any black smoke just some grey smoke so I'm guessing the engine is usally clean.
sorry to so long trying to provide as much details as I can this ses is making me mad.
preformance has not lessened car still runs great and still gets 18-19 MPG city and about 26-29 expressway.
Thanks
Hi. First of all, did you use the original bolts on the valley pan, or did you change them with the bolts from Fast? I have also experienced that the fast valley bolts are to high, and prevents the intake to fit properly. I have also seen Fast intake that have cracks after it was forced on with wrong bolts.
Take a paper sheet and put between the intake and the valley pan when you mount it back. When your finished you should be able to take out the paper. if its stock you must find out why, and where.
To check the intake for cracks is easy. Take of the intake. Use two peaces of wood and bolt them on where the cyl heads should be. make sure that all holes are sealed. Use some strong tape to seal the intake where th TB should be. Spray the intake with soap water and fill the intake with air from a air compressor. Spray sopewater an all parts of the intake and check for cracks. if there is, you will find it. Clean well when Finnish. Chec the pics.
Reg Chris.
Take a paper sheet and put between the intake and the valley pan when you mount it back. When your finished you should be able to take out the paper. if its stock you must find out why, and where.
To check the intake for cracks is easy. Take of the intake. Use two peaces of wood and bolt them on where the cyl heads should be. make sure that all holes are sealed. Use some strong tape to seal the intake where th TB should be. Spray the intake with soap water and fill the intake with air from a air compressor. Spray sopewater an all parts of the intake and check for cracks. if there is, you will find it. Clean well when Finnish. Chec the pics.
Reg Chris.
Thread Starter
Joined: Apr 2004
Posts: 1,378
Likes: 14
From: Atlanta, GA Ft. Walton Beach, FL
leak I purchased a used FAST it did'nt include the button head screw caps bolts for the valley cover I purchased these bolts from Ace hardware.
I'm thinking I could do the paper test without removing the manifold BTW good idea.
plan on trying to reglue MAP sensor without removing manifold.
I also think this SES light is from an dirty fuel injector any thoughts?
Thanks Guys for advice
I'm thinking I could do the paper test without removing the manifold BTW good idea.
plan on trying to reglue MAP sensor without removing manifold.
I also think this SES light is from an dirty fuel injector any thoughts?
Thanks Guys for advice
