Flash! Then it's GONE?
Thread Starter
Racer
Joined: Aug 2002
Posts: 369
Likes: 11
From: NV
Flash! Then it's GONE?
Car is running fine, BUT whenever I decide to REALLY bury my foot in the gas, as I get going I get a strange sensation in the pedal, the check engine light flashes on and off and when I back off the light stops after a few more flashes. Car then runs normally. No codes thrown....keeps happening. At its peak it feels as if it is losing power, maybe missing slightly but I get no codes. Any ideas?
Drifting
Joined: Feb 2005
Posts: 1,770
Likes: 0
From: in ur mirror, 'bout to pass.. CA
No answer, but I can relate! Had it happen to me this weekend while on the track! Only once though. I'm listening too....
Last edited by Armycop; Oct 15, 2007 at 10:49 PM. Reason: imadumass
Le Mans Master
Joined: Nov 2005
Posts: 6,993
Likes: 25
Safety Car
Joined: Sep 2003
Posts: 3,558
Likes: 2
From: Cape Coral FL
Flashing MIL is a cat warning. It could be brought on by misfire though as that would be dumping raw fuel into them, causing them to overheat. When you go WOT PE richens the fuel mixture from 14.7:1 to ~13:1. If you run rich in the first place you could be dumping unburned fuel into the cats causing them to overheat.
Drifting
Joined: Feb 2005
Posts: 1,770
Likes: 0
From: in ur mirror, 'bout to pass.. CA
AArgh, Ye be Hijacked!!
Ah Ha! that would make sense in my case, since we were WOT twice a circuit, on the straights and through the kink at 5&6!
So, I've got nothing to worry about?
Ah Ha! that would make sense in my case, since we were WOT twice a circuit, on the straights and through the kink at 5&6!
So, I've got nothing to worry about?
Le Mans Master
Joined: Dec 2000
Posts: 9,915
Likes: 1,870
From: Hot Springs AR
I've never heard of a flashing MIL being a "cat" warning. The only sensor associated with the cat is the downstream O2 sensor. If that sensor shows poor performance for some period of time, then a code is set identifying "Poor Converter Performance" or similar wording. It's a steady MIL.
The flashing MIL is, as said above, indicating a current misfire situation. If you have access to a scanning tool (not just codes), the PCM will tell you the number of misfires for each cylinder. I use Autotap, but there are many others on the market. Or you can go to your friendly auto shop and pay them $$ to have the same thing done.
HTH, and have a good one,
Mike
The flashing MIL is, as said above, indicating a current misfire situation. If you have access to a scanning tool (not just codes), the PCM will tell you the number of misfires for each cylinder. I use Autotap, but there are many others on the market. Or you can go to your friendly auto shop and pay them $$ to have the same thing done.
HTH, and have a good one,
Mike
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Verdad Gallardo
Safety Car
Joined: Sep 2003
Posts: 3,558
Likes: 2
From: Cape Coral FL
I stand corrected as per Mike's post. If you're mixture is not right at the sensors due to a misfire. It also could be one or both rear O2 sensors. I had the problem with flashing MIL with bad rear O2's. I would start at the Rear O2 sensors. They aren't cheap so it would be a waste of about $250-$300 to swap them out to find it's something else. A good scanner could let you monitor the O2's output. It should be like a series of shark fin's, or sinewave like in nature. If they are flatlined or just moving minimally they could be going out. If you can't get a scanner and you can get them out you could test them with a propane torch and a voltmeter.
See this link, go to the bottom: Testing an O2 sensor.
When I had the flashing MIL I had no misfire codes and my scanner wasn't reporting any misfires above the normal amount.
Also, try ohming your wires then check your spark plugs for cracks in the porcelin if they ohm good.
See this link, go to the bottom: Testing an O2 sensor.
When I had the flashing MIL I had no misfire codes and my scanner wasn't reporting any misfires above the normal amount.
Also, try ohming your wires then check your spark plugs for cracks in the porcelin if they ohm good.
Last edited by ArKay99; Oct 16, 2007 at 01:17 PM.