Baffeling L98 Engine Start Issue
Thread Starter
Racer
Joined: Oct 2000
Posts: 476
Likes: 0
From: Socorro New Mexico
Baffeling L98 Engine Start Issue
I have been having this problem off and on. The Vette never fails to start up when it has been setting for awhile, hot or cold engine symtoms are the same. The fuel pressure holds for a long time.
Anway the Vette will start and idle fine, runs great. But once in awhile (getting more frequent) at idle the thing just dies. It will crank over but not fire.
It is not flooded, no fuel smell. It just won't fire. I got suspuciuos, so, I poured a shot of gas into the throttle body during one of its spells and it fired right up immeaditely and kept running. I then let it idle down for a minute and shut it off. Again no start, another shot of gas and voila, it starts right up and runs fine. P.S. I had my fuel pressure gauge hooked up and had 45 lbs of pressure.
Any ideas, on why it is acting like this.
Obviously it is not getting fuel past the injectors during these re-start times.
Has anyone else experienced this? Help
Anway the Vette will start and idle fine, runs great. But once in awhile (getting more frequent) at idle the thing just dies. It will crank over but not fire.
It is not flooded, no fuel smell. It just won't fire. I got suspuciuos, so, I poured a shot of gas into the throttle body during one of its spells and it fired right up immeaditely and kept running. I then let it idle down for a minute and shut it off. Again no start, another shot of gas and voila, it starts right up and runs fine. P.S. I had my fuel pressure gauge hooked up and had 45 lbs of pressure.
Any ideas, on why it is acting like this.
Obviously it is not getting fuel past the injectors during these re-start times.
Has anyone else experienced this? Help
Team Owner
Joined: Mar 2000
Posts: 83,383
Likes: 87
From: Boston, MA
Re: Baffeling L98 Engine Start Issue (Rynda)
For the sake of trying something check your injector fuses. Also monitor your TPS readings during restart. If the ECM sees a high TPS voltage level during cranking it kills the fuel injectors. It is a flooded engine start mode which provides no fuel to the engine.
Melting Slicks
Joined: Jun 2002
Posts: 2,168
Likes: 16
From: Phoenix AZ
Re: Baffeling L98 Engine Start Issue (Rynda)
Most intermittent problems turn out to be electrical. It still may not be the fuel system, I had similar problems on my '86 and several troubleshooting attempts led me in the wrong direction because I thought that I had done something to affect the way the car's motor reacted when it was really only the intermittent problem going away. My problem turned out to be corroded wiring at the MAF relays behind the battery (pretty common) It wasn't until it threw a code 34 that I even started looking at the MAF circuit. I keep bringing this one up when I see one of these threads because I just know SOMEDAY someone is going to have the same problem... :D
[Modified by vetracer, 9:11 PM 10/13/2003]
[Modified by vetracer, 9:11 PM 10/13/2003]
Pro
Joined: Jul 2002
Posts: 729
Likes: 4
From: Yukon OK
Re: Baffeling L98 Engine Start Issue (Rynda)
Trying to remember the fuel pump circuit. When you first turn it on it gets power from the fuel pump relay controled by the ECM. But it has a back up connection thru an oil pressure switch behind the distributor. So.... if you once get it going the oil pressure will come up and then it will continue to run. Might be a relay going bad??
Team Owner
Joined: Mar 2001
Posts: 54,124
Likes: 30
From: Cincinnati, Oh USA
Re: Baffeling L98 Engine Start Issue (Rynda)
When it won't restart, put a low power 12v lamp across an injector socket and see if it is being pulsed when you crank the engine. If not, check your inj fuses and the condition of the fuse clips for cleanliness. Otherwise you might check VATS (but if VATS is preventing inj pulses, it won't allow a crank either). Check the ECM fuse and finally, swap a known good ECM.
