Can a vacuum leak cause Code 34?
06-01-2007, 07:23 AM
#1
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Can a vacuum leak cause Code 34? Which is MAP/MAF too low. I don't know if it means voltage or pressure *shrug*. The vacuum leak would be of substantial size, like the EGR port being very lose 
I tried to bend the pipe up away from the manifold to put a rubber hose on to plug it, and the bending was actually the pipe moving in the intake. So now it's VERY lose back there :\ I can't hear anything, but I guess I could always spray back there with carb/brake cleaner and see if it revs up. I can get back there with a stubby wrench and socket, but it's a total pain in the ***.
It's also a bit of a coincidence... I had unplugged my MAP yesterday evening while the car was running, for ***** and giggles really. I plugged it back in and made sure it clicked, but I can't see that causing the problem...
Any ideas?
I tried to bend the pipe up away from the manifold to put a rubber hose on to plug it, and the bending was actually the pipe moving in the intake. So now it's VERY lose back there :\ I can't hear anything, but I guess I could always spray back there with carb/brake cleaner and see if it revs up. I can get back there with a stubby wrench and socket, but it's a total pain in the ***.It's also a bit of a coincidence... I had unplugged my MAP yesterday evening while the car was running, for ***** and giggles really. I plugged it back in and made sure it clicked, but I can't see that causing the problem...
Any ideas?
06-01-2007, 06:22 PM
#3
set the same code on my friends 2.2 cl. we were working late and forgot the set a gasket right. bad vacuum leak and the code. also had a surging idle. fixed the leak and the code didnt come back. a leak could def cause the code to be set
06-01-2007, 07:18 PM
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lol I never have weekend plans :\ I live a crap life, and these small things don't help. It doesn't perform any worse, which is kinda odd seeing as, even though it's not MAF, it's unmetered air via TPS/throttle angle
06-01-2007, 08:18 PM
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vacuum leaks can be very bad,could be that the code was set during your removal of the wiring harness. still the vacuum leak can cause a lean misfire also leanburns are much hotter and if let go long enough can melt pistons, lean fisfires will cause the cylinder wall "wash down" or the unburned fuel can wash the oil coating away, causing lower compression, all of these senerios are bad so fix the leak, clear the code, and if it comes on again , check the maf but I'm almost sure the leak set the code.
