code 91 problems
07-09-2008, 09:24 PM
#1
5th Gear Member
Thread Starter
Join Date: Aug 2006
Location: Haverhill, MA
Posts: 3,664
code 91 problems
i got a CEL this morning
codes 33, 44 and 91 i believe
33 EGR not detected, system lean
44 bank 1 system LEAN
91 bank 1 LEAN circuit not switching
Fuel psi is at 39 idle
02's are new
fuel filter is new
think i found my bucking problem... whats next, the pump?
codes 33, 44 and 91 i believe
33 EGR not detected, system lean
44 bank 1 system LEAN
91 bank 1 LEAN circuit not switching
Fuel psi is at 39 idle
02's are new
fuel filter is new
think i found my bucking problem... whats next, the pump?
07-09-2008, 09:31 PM
#2
D.R. THE PATHETIC DORK
Join Date: Jun 2007
Location: West Virginia
Posts: 30,863
RE: code 91 problems
do you have an exhaust leak at all on bank one???...if it were lean all the way around both banks would be listed most likely as lean and a fuel pump would affect system as a whole not just one bank.......If it were me I'd back probe the signal wires on the o/2 on bank one with a dvom and see if the o/2 on that bank is switching
..also make sure the ground is hooked up to the head
..also make sure the ground is hooked up to the head
07-09-2008, 09:35 PM
#3
5th Gear Member
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Join Date: Aug 2006
Location: Haverhill, MA
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RE: code 91 problems
which side is bank 1?
i got an exhaust leak somewhere but its after the mufflers
everything smog related has been removed
my drivers tail pipe is cracked in half but i think there may be a leak where the h-pipe bridges
i got an exhaust leak somewhere but its after the mufflers
everything smog related has been removed
my drivers tail pipe is cracked in half but i think there may be a leak where the h-pipe bridges
07-09-2008, 09:48 PM
#5
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Join Date: Aug 2006
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RE: code 91 problems
ok.. so would these LEAN codes trigger the EGR to not function?
when i first got the car it had no 02 sensors and there was an EGR code.
i put new 02's in and cleared the EGR code and everythings been great untill today.
kinda weird
when i first got the car it had no 02 sensors and there was an EGR code.
i put new 02's in and cleared the EGR code and everythings been great untill today.
kinda weird
07-09-2008, 09:59 PM
#8
D.R. THE PATHETIC DORK
Join Date: Jun 2007
Location: West Virginia
Posts: 30,863
RE: code 91 problems
I'd make sure that carbon is not holding pintle partially open which will cause a lean condition and make sure the evp sensor is functioning correctly and you can test valve operation by applying vaccum to valve manually and listen for a rough run when applying vaccum....you can also run a koer test with vaccum gauge T'ED in at connection on valve and when egr test is run on the koer test ..you'll see vaccum on the gauge jump briefly....this will indicate evr selonoid is operational..and if valve is fuctioning and not hanging open partially then it may need a evp sensor to fix egr code
07-09-2008, 10:15 PM
#10
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Join Date: Jan 2006
Location: Puerto Rico
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RE: code 91 problems
In your case..... CEL turning on = code 91 (bank 2 lean, HEGO detected not switching). Code 33 (EGR not opening) will not cause the CEL to turn on, and the EEC has deleted the EGR function automatically. Even though the O2's are brand new, you could have a defective LH sensor.... if the O2 failing was bank 1, the code would be 41. The presence of code 44 in a KOER, and not code 94 = the LH or bank 2 HEGO is not switching to a rich condition the system does to test the thermactor system. If the exhaust system has no leaks, that side O2 could be defective, or a problem in the signal wire could be present (open).