NO spark z28 Please help
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From: Miami,FL
NO spark z28 Please help I have a 1994 z28 camaro. I am getting no spark but i am getting fuel. I saw a website with the diagram for the wiring for the opti and A and D should have 10 to 12v but they both have none and the red wire which is C is getting power and it is supposed to be grounded
http://shbox.com/1/95_ign_system_schematic.jpg
I was thinking if there would be anyway to avoid this and just provide the spark from an outside source or what would cause this power issue in the wires, please help
http://shbox.com/1/95_ign_system_schematic.jpg
I was thinking if there would be anyway to avoid this and just provide the spark from an outside source or what would cause this power issue in the wires, please help
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From: Little Rock, AR
Are you testing the right thing in the right place? You might be confusing the opti harness with the ICM harness.
http://shbox.com/1/4th_gen_tech2.html#opti_test
http://shbox.com/1/4th_gen_tech2.html#opti_test
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Ok...update...got her to turn over....changed thedizzy...now just have to get her to stay on....im not sure if it is the security or not...she doesnt really idle...real choppy for a few secs(maybe 400 rpm) then cuts off...im going to check the spark plug wiring, also i did a partial security bypass...just the yellow and black wire to make the key work...the light still blinks so what else do I have to do?
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Update....put everything back together...runs the same...BUTTT......I figure something out....if i plug and unplug the sensor thats on the top of intake on the passenger side behind the throttle body, it revs up......if i plug is...idles low 700rpm, unplug, same thing....im thinking its starving of air....once again im still beat :/ any suggestions/ideas
Did you or anyone rebuild or swap the engine on this car?
You may have some wiring issues, wires switched around or something but if no one has messed with the car that's probably not an possibility... Just an idea.
Have you checked your TPS/IAC sensors? Make sure your IAC is functioning properly and on Shbox's site there are walk throughs and diagrams for everything... check your TPS voltage. I chased down erratic idle problems for a long time and the TPS voltage and a bad IAC were the culprits.
You may have some wiring issues, wires switched around or something but if no one has messed with the car that's probably not an possibility... Just an idea.
Have you checked your TPS/IAC sensors? Make sure your IAC is functioning properly and on Shbox's site there are walk throughs and diagrams for everything... check your TPS voltage. I chased down erratic idle problems for a long time and the TPS voltage and a bad IAC were the culprits.
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Joined: Dec 2011
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From: Miami,FL
Did you or anyone rebuild or swap the engine on this car?
You may have some wiring issues, wires switched around or something but if no one has messed with the car that's probably not an possibility... Just an idea.
Have you checked your TPS/IAC sensors? Make sure your IAC is functioning properly and on Shbox's site there are walk throughs and diagrams for everything... check your TPS voltage. I chased down erratic idle problems for a long time and the TPS voltage and a bad IAC were the culprits.
You may have some wiring issues, wires switched around or something but if no one has messed with the car that's probably not an possibility... Just an idea.
Have you checked your TPS/IAC sensors? Make sure your IAC is functioning properly and on Shbox's site there are walk throughs and diagrams for everything... check your TPS voltage. I chased down erratic idle problems for a long time and the TPS voltage and a bad IAC were the culprits.
Ok i followed the diagram http://shbox.com/1/iac2.jpg
but im reading 12.19 on both A and B & C and D...i have my meter set to DCV 20.....am i testing the right plug?? its to the sensor to the bottom of the throttle body
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Joined: Dec 2008
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From: Little Rock, AR
Ok i followed the diagram http://shbox.com/1/iac2.jpg
but im reading 12.19 on both A and B & C and D...i have my meter set to DCV 20.....am i testing the right plug?? its to the sensor to the bottom of the throttle body
but im reading 12.19 on both A and B & C and D...i have my meter set to DCV 20.....am i testing the right plug?? its to the sensor to the bottom of the throttle body
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From: Miami,FL
So the IAC has a charge of its own??? well im not getting anything from it, do you think it could be the meter im using? and if not I guess that means I need a new one??? And something interesting to note....I started the car with the throttle body completely off, I was expecting the car to roar out of control or at least max out rpm but it did nothing, rpms stayed under 700 with NO throttle body at ALL which made me think that it wasnt any senors on the throttle body, what do you think?
http://i.walmartimages.com/i/p/00/04...00_500X500.jpg
Thread Starter
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Joined: Dec 2011
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From: Miami,FL
Did you or anyone rebuild or swap the engine on this car?
You may have some wiring issues, wires switched around or something but if no one has messed with the car that's probably not an possibility... Just an idea.
Have you checked your TPS/IAC sensors? Make sure your IAC is functioning properly and on Shbox's site there are walk throughs and diagrams for everything... check your TPS voltage. I chased down erratic idle problems for a long time and the TPS voltage and a bad IAC were the culprits.
You may have some wiring issues, wires switched around or something but if no one has messed with the car that's probably not an possibility... Just an idea.
Have you checked your TPS/IAC sensors? Make sure your IAC is functioning properly and on Shbox's site there are walk throughs and diagrams for everything... check your TPS voltage. I chased down erratic idle problems for a long time and the TPS voltage and a bad IAC were the culprits.
I almost thought i had the solution with the opti vacuum but i see the 94 uses a U shaped pcv valve :\ and while i was checking my plugs a few minutes ago i cam across something else. As far as I know the z28 comes with a 350??? They why da hell does my case say 327!!! On both sides.....so apparently they did do a swap, unless im mistaken and some z's came with 327s....I mean if that info helps then I hope we can find a solution, and the lines to the secondary AIR pump are bent to prevent air to enter. Even though its a 327 they used the z28 intake mani so i wouldnt think it would really make a difference I havent checked the vacuum pressure yet and I dont have access to a diagnostics yet but seeing as though the fuel pressure is right im almost certain its a vacuum issue...Another fix I made upon looking through shbox's page, my MAF was on backwards smh, I noticed in the pic the sensor plugged in on the top and mines was facing down, do you think that will fix the problem? I have to get another starter tomorrow and im curious to see if that was it
You are jumping all over the place in your diagnosis. Did this car ever run right, what happened when the no spark condition occured. You say you fixed the spark by putting on an opti and now it turns over, an opti won't prevent the engine from cranking. Did it crank and not start or not crank at all? Now your chasing vacuum connections. I'm confused!
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From: Miami,FL
You are jumping all over the place in your diagnosis. Did this car ever run right, what happened when the no spark condition occured. You say you fixed the spark by putting on an opti and now it turns over, an opti won't prevent the engine from cranking. Did it crank and not start or not crank at all? Now your chasing vacuum connections. I'm confused!
I'm sorry about the confusion, it was cranking and not starting and I went thru the process to figure out what component it was, and i was right, now the car starts but I get no response from the throttle, I disabled the security by the way
Did it ever run right and if so what happened to put you where your at? What do you mean no response from the throttle? Does it start and idle? What happens when you start to open the throttle? What's been done to the car as far as aftermarket things?
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From: Miami,FL
Well I got the car like this so as far as the history I have no clue, as far as after market, everything looks stock except for MAYBE the exhaust tips, and I start the car, it would idle around 700rpm, press the gas nothing happens. I even started the car without the throttle body just for testing purposes expecting the rpm to surge up and surely enough it stay right at 700rpm
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From: Miami,FL
I have NO reason to lie...I figured with no TB it would just roar up the rpm gauge, it did nothing but stay at 700rpms which led me to believe that it doesnt have anything to do with any of the sensors on the throttle body itself...the exhaust smells rich so I was thinking maybe it was an air issue, but it could definitely be a vacuum issue...I just some ideas to see what to mess with since i dont have a diagnostic and someone also said maybe my pcm might be in limp mode
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From: Miami,FL
Hey guys, so I put everything back together, but this time I did a compression test... I only tested one so far but the result was soo bad I'm clueless...on #1 I got 60psi and it didn't even stay up on the Gauge...so would that be caused by my valves? If not then what could cause this?
Hey guys, so I put everything back together, but this time I did a compression test... I only tested one so far but the result was soo bad I'm clueless...on #1 I got 60psi and it didn't even stay up on the Gauge...so would that be caused by my valves? If not then what could cause this?
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From: Miami,FL
Put the car back togther(not done yet)....heres my results...
http://youtu.be/bfwtilFQtNA
http://youtu.be/VxQBi6gfPJ8
http://youtu.be/bfwtilFQtNA
http://youtu.be/VxQBi6gfPJ8