1994 z28 Please HELP!
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Teching In
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1994 z28 Please HELP! Hi everyone I am having a problem with my 94 lt1. would stall the check gauges light would come on and would not restart until cooled down. New fuel pump x2 filter. Fuel pressure with the key on stays at 40psi and will not bleed down for awhile. it will fire with starting fluid. but now it won't stay running. This past weekend I pulled the opti it had some oil in it so I cleaned it up replaced the cap and rotor. sealed it up good I hope the sensor is good. Put new plugs and wires on it, deleated the air pump. It don't have a cat on it. here is the list of other new parts i have been throwing at it. PCM, ICM, Coil, TPC, Water temp sensor. I have pulled all injectors and cleaned out them with a 9 volt and carb cleaner. Cleaned the fuel rail. I do not have a obd1 scanner, but when I tried to use a jumper all it will do is turn the fans on. no flashing. Thanks for any help.
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Joined: Dec 2010
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From: Maricopa, AZ
1994 z28 Please HELP! NOT optispark. The optispark will cut fuel AND spark. So it won't start at all no matter what you spray in it. So you can eliminate that for the most part.
If the car starts with starting fluid, it's a fuel issue. I'd verify the injectors are actually firing. Pull both rails and watch them as someone else cranks the car over.
94 and 95 F-bodies are OBD1, but will not flash with the jumper on the port. You need a scanning program. You have the 12 pin ALDL port, so you'll need a USB to OBD1 12 pin ALDL cable ($60 or less, or you can make one your self for less than $10 if your savvy in that kind of stuff). Then get your laptop and download Scan9495.exe (Google it, it's free!). Connect your laptop to your car and enjoy.
That program can do more than pull codes as it's a full data logger and you can access ABS and other PCM and BCM functions and manually switch them too (great for bleeding the ABS module). Once you have all that, you're Tuner Pro RT (free too) and WinFlash ($20) from tuning everything on your car your self (gears, tires, exhaust, cam, heads, tb, everything). Not many cars out there can do that for under $100. Most can barely get a code reader for that price.
If the car starts with starting fluid, it's a fuel issue. I'd verify the injectors are actually firing. Pull both rails and watch them as someone else cranks the car over.
94 and 95 F-bodies are OBD1, but will not flash with the jumper on the port. You need a scanning program. You have the 12 pin ALDL port, so you'll need a USB to OBD1 12 pin ALDL cable ($60 or less, or you can make one your self for less than $10 if your savvy in that kind of stuff). Then get your laptop and download Scan9495.exe (Google it, it's free!). Connect your laptop to your car and enjoy.
That program can do more than pull codes as it's a full data logger and you can access ABS and other PCM and BCM functions and manually switch them too (great for bleeding the ABS module). Once you have all that, you're Tuner Pro RT (free too) and WinFlash ($20) from tuning everything on your car your self (gears, tires, exhaust, cam, heads, tb, everything). Not many cars out there can do that for under $100. Most can barely get a code reader for that price.
Last edited by hrcslam; Aug 14, 2015 at 01:16 PM.
Teching In
Joined: May 2014
Posts: 23
Likes: 0
NOT optispark. The optispark will cut fuel AND spark. So it won't start at all no matter what you spray in it. So you can eliminate that for the most part.
If the car starts with starting fluid, it's a fuel issue. I'd verify the injectors are actually firing. Pull both rails and watch them as someone else cranks the car over.
94 and 95 F-bodies are OBD1, but will not flash with the jumper on the port. You need a scanning program. You have the 12 pin ALDL port, so you'll need a USB to OBD1 12 pin ALDL cable ($60 or less, or you can make one your self for less than $10 if your savvy in that kind of stuff). Then get your laptop and download Scan9495.exe (Google it, it's free!). Connect your laptop to your car and enjoy.
That program can do more than pull codes as it's a full data logger and you can access ABS and other PCM and BCM functions and manually switch them too (great for bleeding the ABS module). Once you have all that, you're Tuner Pro RT (free too) and WinFlash ($20) from tuning everything on your car your self (gears, tires, exhaust, cam, heads, tb, everything). Not many cars out there can do that for under $100. Most can barely get a code reader for that price.
If the car starts with starting fluid, it's a fuel issue. I'd verify the injectors are actually firing. Pull both rails and watch them as someone else cranks the car over.
94 and 95 F-bodies are OBD1, but will not flash with the jumper on the port. You need a scanning program. You have the 12 pin ALDL port, so you'll need a USB to OBD1 12 pin ALDL cable ($60 or less, or you can make one your self for less than $10 if your savvy in that kind of stuff). Then get your laptop and download Scan9495.exe (Google it, it's free!). Connect your laptop to your car and enjoy.
That program can do more than pull codes as it's a full data logger and you can access ABS and other PCM and BCM functions and manually switch them too (great for bleeding the ABS module). Once you have all that, you're Tuner Pro RT (free too) and WinFlash ($20) from tuning everything on your car your self (gears, tires, exhaust, cam, heads, tb, everything). Not many cars out there can do that for under $100. Most can barely get a code reader for that price.
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TECH Addict
Joined: Dec 2010
Posts: 2,610
Likes: 4
From: Maricopa, AZ
1994 z28 Please HELP! What's funny is that it can't be the opti, because of how it works. It could've been the cap and rotor (attached to the opti), but it can't be the opti.
Too many times people toss prefectly good optis (usually Delco or Delphi) when all that is needed is a cap and rotor (much cheaper). They end up replacing the opti with a cheapo unit (anything not Delco or Delphi), then the opti breaks "again" in 6 months or so, and it's the optis fault......
People, if you have fuel OR spark, it's not the Opti. Proper troubleshooting can save you time and money.
Too many times people toss prefectly good optis (usually Delco or Delphi) when all that is needed is a cap and rotor (much cheaper). They end up replacing the opti with a cheapo unit (anything not Delco or Delphi), then the opti breaks "again" in 6 months or so, and it's the optis fault......
People, if you have fuel OR spark, it's not the Opti. Proper troubleshooting can save you time and money.
Last edited by hrcslam; Sep 16, 2015 at 06:21 PM.