Car died while driving
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Car died while driving
I have a 93 z28 A4 and The last few days the car has been like almost dying at times while driving. The car feels like it shuts off but then kinda turns itself on and drives. Today on my way to school the car actually died and I had to pull over and turn it back on. It took a few seconds then longer to crank but turned on and drove. On the way home it almost died but it kinda revved itself up a little bit when it happened and the car kept going. I noticed this morning when I first turned the car on it was reviving as if it had a vacuum leak. I also noticed the car has a small crack in the fresh air Pcv hose and I don’t know if this could have something to do with it? The car also sometimes will hesitate once at highway speed.
Last edited by Logan Jones; Aug 20, 2019 at 02:32 PM.
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Re: Car died while driving
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Re: Car died while driving
You hook a fuel pressure test gauge, with a long hose, to the test port (Schrader valve) on the fuel rail assembly. On a 93 (only) the Schrader valve is on the driver side fuel supply hard line near where the flexible lines connect to the hard lines (which attach to the fuel rails).
You can usually borrow (or rent) a test gauge from many auto parts stores.
You can usually borrow (or rent) a test gauge from many auto parts stores.
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Re: Car died while driving
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From: Hell was full so they sent me to NJ
Re: Car died while driving
That looks like the EVAP purge line that connects to the black EVAP purge solenoid. The bracket the solenoid connects to appears to have broken or fallen off. It should be screwed onto the side of the intake manifold, see the screw hole in the manifold right behind the tape.
While that line runs from the back of the car near the fuel tank, and is bundled with the fuel supply and return lines, it is used to pull fuel vapor out of the carbon canister in the driver side rear fender, near the gas tank fill pipe. It does not carry fuel. Engine vacuum pulls air in through the carbon canister, and it pulls out the fuel vapor that has been adsorbed by the carbon bed.
If either line taped to the EVAP solenoid is leaking, it creates a vacuum leak. But it shouldn’t cause the engine to die.
Here's what it is supposed to look like, at least on the 94-97 LT1’s. The 93 may be slightly different. In 94 the purge line runs around the front of the manifold, under the throttle body. 93 may be routed from the back.... or maybe someone hacked it up and ran the line from the back of the engine
http://shbox.com/1/evap_sol.jpg
While that line runs from the back of the car near the fuel tank, and is bundled with the fuel supply and return lines, it is used to pull fuel vapor out of the carbon canister in the driver side rear fender, near the gas tank fill pipe. It does not carry fuel. Engine vacuum pulls air in through the carbon canister, and it pulls out the fuel vapor that has been adsorbed by the carbon bed.
If either line taped to the EVAP solenoid is leaking, it creates a vacuum leak. But it shouldn’t cause the engine to die.
Here's what it is supposed to look like, at least on the 94-97 LT1’s. The 93 may be slightly different. In 94 the purge line runs around the front of the manifold, under the throttle body. 93 may be routed from the back.... or maybe someone hacked it up and ran the line from the back of the engine
http://shbox.com/1/evap_sol.jpg
Last edited by Injuneer; Aug 21, 2019 at 04:23 PM.
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Joined: Feb 2019
Posts: 32
Re: Car died while driving
That looks like the EVAP purge line that connects to the black EVAP purge solenoid. The bracket the solenoid connects to appears to have broken or fallen off. It should be screwed onto the side of the intake manifold, see the screw hole in the manifold right behind the tape.
While that line runs from the back of the car near the fuel tank, and is bundled with the fuel supply and return lines, it is used to pull fuel vapor out of the carbon canister in the driver side rear fender, near the gas tank fill pipe. It does not carry fuel. Engine vacuum pulls air in through the carbon canister, and it pulls out the fuel vapor that has been adsorbed by the carbon bed.
If either line taped to the EVAP solenoid is leaking, it creates a vacuum leak. But it shouldn’t cause the engine to die.
Here's what it is supposed to look like, at least on the 94-97 LT1’s. The 93 may be slightly different. In 94 the purge line runs around the front of the manifold, under the throttle body. 93 may be routed from the back.... or maybe someone hacked it up and ran the line from the back of the engine
http://shbox.com/1/evap_sol.jpg
While that line runs from the back of the car near the fuel tank, and is bundled with the fuel supply and return lines, it is used to pull fuel vapor out of the carbon canister in the driver side rear fender, near the gas tank fill pipe. It does not carry fuel. Engine vacuum pulls air in through the carbon canister, and it pulls out the fuel vapor that has been adsorbed by the carbon bed.
If either line taped to the EVAP solenoid is leaking, it creates a vacuum leak. But it shouldn’t cause the engine to die.
Here's what it is supposed to look like, at least on the 94-97 LT1’s. The 93 may be slightly different. In 94 the purge line runs around the front of the manifold, under the throttle body. 93 may be routed from the back.... or maybe someone hacked it up and ran the line from the back of the engine
http://shbox.com/1/evap_sol.jpg
Last edited by Logan Jones; Aug 21, 2019 at 06:28 PM.
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Re: Car died while driving
The only harm is that dirty, unfiltered air is entering the engine. If it had an MAF sensor like the 94-97 LT1’s it would be a problem with air bypassing the MAF. But your 93, with no MAF sensor, runs speed-density, which calculates mass air flow based on RPM, manifold absolute pressure (MAP), and (absolute) inlet air temperature (IAT).
The torn inlet elbow needs to be replaced, but it isn’t causing the engine to die.
Fuel pressure sounds OK. If it runs, take it out on the highway and see if the pressure stays above 40 PSI at wide open throttle, over 5,000 RPM.
The torn inlet elbow needs to be replaced, but it isn’t causing the engine to die.
Fuel pressure sounds OK. If it runs, take it out on the highway and see if the pressure stays above 40 PSI at wide open throttle, over 5,000 RPM.
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Joined: Feb 2019
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Re: Car died while driving
The only harm is that dirty, unfiltered air is entering the engine. If it had an MAF sensor like the 94-97 LT1’s it would be a problem with air bypassing the MAF. But your 93, with no MAF sensor, runs speed-density, which calculates mass air flow based on RPM, manifold absolute pressure (MAP), and (absolute) inlet air temperature (IAT).
The torn inlet elbow needs to be replaced, but it isn’t causing the engine to die.
Fuel pressure sounds OK. If it runs, take it out on the highway and see if the pressure stays above 40 PSI at wide open throttle, over 5,000 RPM.
The torn inlet elbow needs to be replaced, but it isn’t causing the engine to die.
Fuel pressure sounds OK. If it runs, take it out on the highway and see if the pressure stays above 40 PSI at wide open throttle, over 5,000 RPM.
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