'96 Z28 Throwing codes
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'96 Z28 Throwing codes
Alright my '96 Z28 is throwing these 5 codes,
1. P0100. MAF or VAF Circuit Failure.
2. P0300. Random Misfire.
3. P0441 EVAP Control Bad Purge Flow.
4. P0443 EVAP Purge Control Valve
5. P1642 Fc Relay (2) and Relay (3) Control Circuit
This is as the mechanic wrote it. Does Number 1 mean the MAF is bad or just the wiring? Any way to test it other than just switching it out?
Number 2 is due to fouled plugs I'm guessing due to running extremely rich which would be due to the bad MAF I'm guessing? If I'm sitting at a stop sign with the windows down you can really smell the fumes.
3 and 4 are vacuum related correct? I have one vacuum tube disconnected on the passenger side of the intake and one over by the ABS/Intake area. Would those be the correct causes? Either way I'll be figuring out where they go and hooking them back up.
Number 5 is the Fan relays correct? It did over heat a tad after messing around alittle but other than that it runs good. You can hear them turn on when I turn the ignition to the "On" position after I've been driving it.
Just want to verify what I was told so I know I'm heading in the right direction and so I'm not throwing parts at it or if there are other things that could cause it to throw these codes.
For what it's worth the car has a BBK Throttle Body, Edelbrock Shorty Headers, MSD Ignition and Moroso CAI. Could have a aftermarket MAF but I'm pretty sure it's the stock one as it came with a Granatelli MAF uninstalled. From what I've read the stock MAF's are the best though.
1. P0100. MAF or VAF Circuit Failure.
2. P0300. Random Misfire.
3. P0441 EVAP Control Bad Purge Flow.
4. P0443 EVAP Purge Control Valve
5. P1642 Fc Relay (2) and Relay (3) Control Circuit
This is as the mechanic wrote it. Does Number 1 mean the MAF is bad or just the wiring? Any way to test it other than just switching it out?
Number 2 is due to fouled plugs I'm guessing due to running extremely rich which would be due to the bad MAF I'm guessing? If I'm sitting at a stop sign with the windows down you can really smell the fumes.
3 and 4 are vacuum related correct? I have one vacuum tube disconnected on the passenger side of the intake and one over by the ABS/Intake area. Would those be the correct causes? Either way I'll be figuring out where they go and hooking them back up.
Number 5 is the Fan relays correct? It did over heat a tad after messing around alittle but other than that it runs good. You can hear them turn on when I turn the ignition to the "On" position after I've been driving it.
Just want to verify what I was told so I know I'm heading in the right direction and so I'm not throwing parts at it or if there are other things that could cause it to throw these codes.
For what it's worth the car has a BBK Throttle Body, Edelbrock Shorty Headers, MSD Ignition and Moroso CAI. Could have a aftermarket MAF but I'm pretty sure it's the stock one as it came with a Granatelli MAF uninstalled. From what I've read the stock MAF's are the best though.
Last edited by oChristiano; 06-29-2010 at 10:58 PM.
#2
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3 & 4: evap purge valve on the pass. side. One attaches to manifold vacuum on the throttle body and the other goes to the cannister. For reference:
http://www.shbox.com/1/1996_evap.jpg
take a pic of the loose line on the driver's side...
5: Check your fan relays/ wiring
1: a) Check engine sensor fuse (20A), b) check for 12V on pink wire with key on/engine off, c) if you have headers check the heat tape-wrapped part of the engine harness by the pass. side primaries to make sure they're not cooked. If they are, splice in some extra length so you can keep it out of the way and re-wrap with heat tape.
See how far you get...
http://www.shbox.com/1/1996_evap.jpg
take a pic of the loose line on the driver's side...
5: Check your fan relays/ wiring
1: a) Check engine sensor fuse (20A), b) check for 12V on pink wire with key on/engine off, c) if you have headers check the heat tape-wrapped part of the engine harness by the pass. side primaries to make sure they're not cooked. If they are, splice in some extra length so you can keep it out of the way and re-wrap with heat tape.
See how far you get...
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^That diagram is a life saver. Makes life alot easier. Thanks for the info. I hate non car people who try to work on their cars and mickey mouse ****. Having to fix all the previous owners mistakes.
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Okay so Number 11 in that diagram was completely missing. Replaced it and got it all sorted out. On too the next one.
I have this piece below, no idea what it is or what it does. I found the connection for it over by the ABS/Airbox. Any one know what it is? Just spent the last 2 hours at the local Chevy dealer to no avail. Need to figure out the hoses that attach to it.
Not the best pictures so bear with me.
I have this piece below, no idea what it is or what it does. I found the connection for it over by the ABS/Airbox. Any one know what it is? Just spent the last 2 hours at the local Chevy dealer to no avail. Need to figure out the hoses that attach to it.
Not the best pictures so bear with me.
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Rubber elbow goes to the intake (vacuum), the one next to it goes to a hose on the AIR pump. The solenoid should sit with the cap facing straight up, connector and fittings facing front of car...
Edit: location is just behind the water pump, left side- not on the intake itself. You're possibly missing a piece of vacuum line. Didn't want to give the impression that you were to attach it directly to the intake nipple.
Edit: location is just behind the water pump, left side- not on the intake itself. You're possibly missing a piece of vacuum line. Didn't want to give the impression that you were to attach it directly to the intake nipple.
Last edited by Gojira94; 07-01-2010 at 04:50 PM.
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Rubber elbow goes to the intake (vacuum), the one next to it goes to a hose on the AIR pump. The solenoid should sit with the cap facing straight up, connector and fittings facing front of car...
Edit: location is just behind the water pump, left side- not on the intake itself. You're possibly missing a piece of vacuum line. Didn't want to give the impression that you were to attach it directly to the intake nipple.
Edit: location is just behind the water pump, left side- not on the intake itself. You're possibly missing a piece of vacuum line. Didn't want to give the impression that you were to attach it directly to the intake nipple.