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Blinking Check Engine Light

mattstansbury

New member
2001 Grand prix gt, runs perfect. floor it and it pulls just fine...till it gets around 80+ then SOMETIMES the check engine light comes on blinking which i know that means the engine is screaming "Oh F*ck Sh*t" but it makes no noises at all...it does stop pulling but if i let off and it up shifts it will pull agin a bit. if i let off and cruise, or even let it up shift and keep it at 80 the light will go off after maybe a minute, sometimes even 10s after i let off the gas.. Any ideas?. I have put it in first and ran slow all the way up through rpm range with no problems if that helps.
 


flashing means misfire


pull the plugs and look for damage to them, or they are just old and need to be changed.

also the wires may be old aswell and need to be changed.
 
Multiple Misfires is correct.

Along with plugs and wires, check your coil packs.

Stop driving with a flashing CEL. You're gonna blow your motor.
 
Check your plugs for this

photo-2.jpg
 


yes, but the light is NEVER on during normal driving, so should i be really worried about it? I just don't get what speed has to do with the light, figured higher rpms would trigger it in all gears? idk, maybe the gt is confused its going over 60mph lol >.>
 
It's already been said about the blinking light. It's telling you something bad is happening.

Throw a decent scan tool on the car and evaluate the info.

Off the top of my head, at that speed, the torque converter locking up comes to mind.:idk: Just trying to consider what's going on at that speed.

What RPM at 80 are you at? Are you accelerating or does it only happen when cruising.
 
it happens when your accelerating, it never happens when cruising at 60, even 70..and 80+ means it has happened at 80mph before, but usually its around 90-100 it starts. I gotta work so ill try and pull the plugs when i get back. How much do plugs,wires, and coilpacks cost on these cars? (never had a 3800 befrore) Any sparkplug/heatrange you'd recommend for better performance?
 
it happens when your accelerating, it never happens when cruising at 60, even 70..and 80+ means it has happened at 80mph before, but usually its around 90-100 it starts. I gotta work so ill try and pull the plugs when i get back. How much do plugs,wires, and coilpacks cost on these cars? (never had a 3800 befrore) Any sparkplug/heatrange you'd recommend for better performance?
I'd suggest slowing down.:D

Also wouldn't just start throwing coil packs or anything expensive on the car.

You should give it a solid tune up. That's a given. I'm not convinced that's your problem though if it's only doing it at high speed and no other ranges. It would be a good idea to get a good scan tool (if problems still exist after tune up) and monitoring what's doing what at the point of failure and at normal operation.
 
it happens when your accelerating, it never happens when cruising at 60, even 70..and 80+ means it has happened at 80mph before, but usually its around 90-100 it starts. I gotta work so ill try and pull the plugs when i get back. How much do plugs,wires, and coilpacks cost on these cars? (never had a 3800 befrore) Any sparkplug/heatrange you'd recommend for better performance?
You are going to end up killing yourself, or worse someone else driving the way you do. Slow down.

Figure out what is wrong with the car before you blow it up.
 


yes, but the light is NEVER on during normal driving, so should i be really worried about it? I just don't get what speed has to do with the light, figured higher rpms would trigger it in all gears? idk, maybe the gt is confused its going over 60mph lol >.>
Mine did the same thing, only upon acceleration above 70 mph. I pulled the plugs and that is what I found.
 
Mine did the same thing, only upon acceleration above 70 mph. I pulled the plugs and that is what I found.

same thing for me! only mine also happened when i accelerated past 90 mph. light blinked and was off by the time i got home. had some mileage on it and i know i needed a tune up. pulled my plugs, and cylinder 2 was f**ked but not as bad as that one up there ^^^ lol plugs are cheap and dont hurt to get knew ones. throw those in and if you want get wires too. then see what happens.
 
should i get plugs and wires anyway? the car has 106,XXX miles. Also, should coil packs be changed?. I've yet to pull the plugs..ah procrastination, but looked at them and they seem like a ***** to get out on the radiator side...didn't look at the back, i was more interested in changing those POS headlight bulbs.
 


Yeah do plugs and wires and go from there. It could really be missing that high up but you're not feeling it because of road conditions or whatever.
 
Flashing check engine light per the FSM's mean that there is a potentially catalyst damaging condition occuring.

Typically it's a misfire of sorts.

What plugs, wires and coils are on the car? Seems like you are getting issues at high rpm. MSD coils are known for this (red and say msd on them)
 
Coil packs are not known for going out. Just like everyone said pull the plugs and don't hotrod it till you do otherwise you might face the dreaded rebuild mod.
 
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