LT1 Dies While Driving
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Joined: Dec 2008
Posts: 5
just bought a 93 Z28, doing the same thing. I can drive it for about 20-30 mins. and it just dies, and will restart and run anywhere from 5 seconds to 5 mins. before it does it again. Just noticed yesterday when it dies I turn the switch off then on and the tack jumps BAD over to about 6000 RPM not running just with switch in on position. The fuel pump runs for about 30 seconds turns off for about 5 then back on, the fans do the same thing and also the check engine light, off then on. It will do that for about 1 min and then I can restart it again. I was thinking ECM but now I'm thinking opti-spark spiking the ECM maybe? When i first bought the car it sputtered on take off but after 2000 RPM was fine. This thing is driving me crazy any help would be greatly appreciated.
Registered User
Joined: Aug 2000
Posts: 3,523
From: TX
I had a problem with mine running and dying. If I let it sit for a while it would start right back up and run fine... then it would start to chug and act stupid. I had a VERY leaky intake gasket. Pulled the intake and cleaned all the sensors on the intake, resealed, and it ran fine after that.
Administrator
Joined: Nov 1998
Posts: 71,110
From: Hell was full so they sent me to NJ
just bought a 93 Z28, doing the same thing. I can drive it for about 20-30 mins. and it just dies, and will restart and run anywhere from 5 seconds to 5 mins. before it does it again. Just noticed yesterday when it dies I turn the switch off then on and the tack jumps BAD over to about 6000 RPM not running just with switch in on position. The fuel pump runs for about 30 seconds turns off for about 5 then back on, the fans do the same thing and also the check engine light, off then on. It will do that for about 1 min and then I can restart it again. I was thinking ECM but now I'm thinking opti-spark spiking the ECM maybe? When i first bought the car it sputtered on take off but after 2000 RPM was fine. This thing is driving me crazy any help would be greatly appreciated.
Registered User
Joined: Sep 2001
Posts: 432
From: Cincinnati,ohio, usa
for mine car dying it never turns on the SES light. One time i noticed it was on i can to get the lap top but it turned off. It only comes on for a quick second and as soon as i notice it, its gone
Registered User
Joined: Dec 2008
Posts: 5
The only code I get is a 26 (EVAP purge control solenoid circuit). In the post above when mine comes on it's kinda like iv'e jumped the pins but I didnt. It will come on for 5-10 seconds and off for about 5-10 seconds then back on, and the fan comes on and off at the same time. And when it dies sometimes it sputters and backfires and sometimes not. My front crank seal is leaking so maybe oil getting in the opti?
Last edited by don10m; Dec 23, 2008 at 08:56 AM.
Administrator
Joined: Nov 1998
Posts: 71,110
From: Hell was full so they sent me to NJ
The only code I get is a 26 (EVAP purge control solenoid circuit). In the post above when mine comes on it's kinda like iv'e jumped the pins but I didnt. It will come on for 5-10 seconds and off for about 5-10 seconds then back on, and the fan comes on and off at the same time. And when it dies sometimes it sputters and backfires and sometimes not. My front crank seal is leaking so maybe oil getting in the opti?
http://shbox.com/1/Dtcs.htm
Note that the 93 is unique, and has its own code definition column on the right side of the page. 93 still used the "quad driver modules".... so its different than all the newer LT1's.
DTC 26 = Quad-Driver Module (QDM) #1 circuit applies to:
- AIR pump relay circuit
- EGR solenoid
- EVAP solenoid
Registered User
Joined: Dec 2008
Posts: 5
Well took the ECM and put it in a friends 1993 Z28 ran fine so im in the process of taking the OPTI off, will let everyone know if this was it(Fingers crossed). Oh and one more thing, every opti-spark I see online for sale says without module, what module are they talking about, everyone i call has no idea.Thanks for everyones help.
Administrator
Joined: Nov 1998
Posts: 71,110
From: Hell was full so they sent me to NJ
Don't go looking for a cheap Opti online, without assurance its the 'real thing'. Get a genuine Delphi unit, the complete unit, not just the cap & rotor. I genuine Delphi part will include everything - shouldn't have a "module not included" qualifier. I believe "thepartsladi" sells them fairly cheap on eBay, and people have had good luck with them. Many others advertise "OEM" parts, but they are not, and fail quickly.
Registered User
Joined: Feb 1999
Posts: 360
From: Rio Rancho, NM
Don't go looking for a cheap Opti online, without assurance its the 'real thing'. Get a genuine Delphi unit, the complete unit, not just the cap & rotor. I genuine Delphi part will include everything - shouldn't have a "module not included" qualifier. I believe "thepartsladi" sells them fairly cheap on eBay, and people have had good luck with them. Many others advertise "OEM" parts, but they are not, and fail quickly.
My "partsladi" opti was shipped quick and was around $265.
Everything was on the up with this unit and came in a nice sealed Delphi box.
I'd recommend as well,
Ivan
Registered User
Joined: May 2021
Posts: 3
From: West valley city, Utah
Re: LT1 Dies While Driving
I searched a few times, but seems no one has had the exact issue I've had with this. Just recently my car has gotten to where it would crank fine when cold, drive fine for maybe 10 minutes, then it would start to cut out and die. In the past it would fire right back up and drive just fine, but last night it did it and would not fire back over at all. After turning it over until the battery was nearly dead hooked it up to my aunts truck to charge the battery, charged about 10 minutes and fired right up. Got it running, and after about 5 minutes it died again and would not start back for the rest of the night. Went this morning, fired right up and drove home no issues. In fact when I got home I let it run for 45 minutes with no problems. When I turn the switch on after it dies I can hear the fuel pump cycle on. Also about once every 4-5 times it does this it pops my gauge cluster fuse. It has only died on me so far at night, when the headlights were on. In fact the other day it was raining, died on me, I turned my lights off and made it to my destination with no more trouble. The car has a new opti with less than 5k, a new ICM with less than 2k, new plugs/wires/fuel filter. I keep it above 1/2 a tank at all times, right now its at 3/4 of a tank when it was doing it. Any help is GREATLY appreciated!!
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