Weird thing happened last weekend.

[cadillac531]

Had the car out last weekend, and was running nice and strong.

On the way home, I did a 25-35ft burnout and it sounded like a champ! All of a sudden, the SES light popped on. All the gauges looked good, nothing sounded out of the ordinary, and no unusual smells. Got the car home, shut it down, fired it back up, the light stayed on for about 2 seconds...and went out.

I've had the car out a couple of times since that and the light hasn't come back on. I haven't had a chance to pull any codes (current or historic), but all seems good.

Anyone have any ideas? Glitch in a sensor or in the ECU?

Not too worried about it, since it seems to have fixed itself. Just thought it was strange.

[QB93Z]

I have had that happen in the past. For me it occurs rarely, and follows a short, full throttle excursion.

The source has never been identified. I suspect that it stems from an intermittent lazy O2 sensor, but I don't have any evidence to prove that.

I guess that if the Lotus/GM engineers wanted a record of the transient, they would have made it a hard fault code.

Jim

[GOLDCYLON]

Pull the codes anyway. You had an error condition that did not set a hard code. It Happens. If I was a betting man it was a secondary issue like a seconary vacuum actuator leak based upon hammerng the car. The rest is specualtion. From o2 sensors to cam sensor fault/

[scottfab]

....snip....
I've had the car out a couple of times since that and the light hasn't come back on. I haven't had a chance to pull any codes (current or historic), but all seems good.

Anyone have any ideas? Glitch in a sensor or in the ECU?

Not too worried about it, since it seems to have fixed itself. Just thought it was strange.

See if it is setting a lean code (left or right).
Could be a fuel pump starting to act up. The bad news is that if it is
you could get stranded (happened to me). I put in an emergency switch that turns on and leaves on pump #2. That is just a guess based on my car.
The key would be to get a scanner on it to record data the walk through the data (assuming you can make it happen again) and see what the O2 sensors are doing and how the fuel trim and throttle position are behaving. Very not likely the secondary actuators since you'd have gotten the symptom during WOT not after.

[cadillac531]

Thanks for the replies. I'll put my scanner on it and see what's happening.

Great idea on the switch for the second pump! I'll have to look into doing that as a safety precaution.

This car's never kicked a code before, so needless to say I was a little concerned when it came on, then a little confused when it went out.

[XfireZ51]

My guess is lean O2.

[Paul Workman]

I too had an O2 issue. Mine was on my 95 LT1, and it was easily spotted with my scanner.

Note: I thought I would force a little RTV into the hole where the wires to the O2 element ran to seal it up. Big mistake!:o Not only does the element need contact with the atmosphere to work, they're very sensitive (read: can be easily destroyed) in the presence of silicon which was introduced by the RTV. (I think I was on my 3rd replacement O2 in as many months before suspicion took over and I figured out what the problem was. Left them alone and no problems for the 4 years I had it before trading it for the Z)