Checking for vacuum leaks... Propane didn't work!
10-11-2012, 12:58 AM
#1
Checking for vacuum leaks... Propane didn't work! I tried the propane method today and it didn't work. I pulled out the PCV line from the intake and opened the propane torch valve all the way, put it right up against the PCV port on the intake where it was sucking in quite a bit of air, and nothing. Engine didn't change speed, sounded exactly the same. Am I doing this wrong? Yes propane was coming out, lots of it.
What else will work?
What else will work?
10-29-2012, 08:58 PM
#6
X2 with starting fluid, or u can use carb cleaner/ electrical contact cleaner/ flammable brake parts cleaner. My personal favorite is brake parts cleaner that's flammable. Also drops bees in a hot second. The little red nozzle straw comes in handy for isolating the spray. One other perk is it will clean ur heads nicely too.
10-29-2012, 09:23 PM
#7
X2 with starting fluid, or u can use carb cleaner/ electrical contact cleaner/ flammable brake parts cleaner. My personal favorite is brake parts cleaner that's flammable. Also drops bees in a hot second. The little red nozzle straw comes in handy for isolating the spray. One other perk is it will clean ur heads nicely too.
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10-30-2012, 10:51 AM
#10
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You need to defeat the IAC, if you're chasing a lean problem
but the idle speed is right. Otherwise IAC will act faster than
you can hear the motor drop RPM.
If the motor is overfueled with an air leak then more fuel
may not make much difference. Stoich or lean, big diff.
but the idle speed is right. Otherwise IAC will act faster than
you can hear the motor drop RPM.
If the motor is overfueled with an air leak then more fuel
may not make much difference. Stoich or lean, big diff.
10-30-2012, 12:25 PM
#11
I have no idea if it's lean, rich, or stoich. Idle speed is right on, but the idle hangs if start moving. Could it be the throttle cracker? And there is some ticking noise. It could be my tune, but I want to rule out what I can.
10-30-2012, 02:40 PM
#12
I'm not going to comment on the possible vacuum leak as there appears to be some backstory that I'm unaware of.
I WILL HOWEVER comment on the use of brake cleaner of any type for locating vacuum leaks. DO NOT COMBUST BRAKE CLEANER!!!!!!!!!!
Chlorine is found in ALL brake cleaners (even the ones that are "chlorine free"). Combine that with carbon monoxide (a combustion byproduct) and then put both through a catalyst and you get PHOSGENE gas.
USE CARB CLEANER
I WILL HOWEVER comment on the use of brake cleaner of any type for locating vacuum leaks. DO NOT COMBUST BRAKE CLEANER!!!!!!!!!!
Chlorine is found in ALL brake cleaners (even the ones that are "chlorine free"). Combine that with carbon monoxide (a combustion byproduct) and then put both through a catalyst and you get PHOSGENE gas.
USE CARB CLEANER
10-30-2012, 08:56 PM
#15
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I think that's actually a pretty safe option. Way back in the days of distributors, I actually caught a 3.0L For Taurus engine on fire because the brakeleen trick caught on fire. Nothing happened and I had an extinguisher close by, but still. Never trusted that diagnosis idea since.
11-07-2012, 11:48 AM
#16
You need to defeat the IAC, if you're chasing a lean problem
but the idle speed is right. Otherwise IAC will act faster than
you can hear the motor drop RPM.
If the motor is overfueled with an air leak then more fuel
may not make much difference. Stoich or lean, big diff.
but the idle speed is right. Otherwise IAC will act faster than
you can hear the motor drop RPM.
If the motor is overfueled with an air leak then more fuel
may not make much difference. Stoich or lean, big diff.
02-27-2013, 10:22 PM
#17
you're supposed to use the propane the same way you would use a spray. you move it around gasket areas or anywhere else air could sneak in. if you unplug the IAC, the computer wont be able to adjust idle speed, so you'll get a truer reading. just move the probe around different things until the RPM increases. do you have like a bank 1/bank 2 lean code or something?
