2001 Tahoe Blinking Check Engine Light?

[Justin509]

2001 Tahoe
205k
5.3
4wd

I just had a trip to Oregon about 1k miles round trip. Just as I got back in town I had my cruise control on and was doing about 65mph and started to go up a hill and I noticed when it went from 1500rpm to 3000pm it was pulsing like it wanted to go faster but it wouldn't like a miss fire. Then I noticed the check engine light blinking. So I turned cruise control off and brought it down to 65mph and about 1800rpm and the blinking check engine light went off.. Then I wot to see if it went away and it did the same thing. Check engine light started blinking... I found a little info saying that when the check engine light blinks that means its a miss fire. So I took it to auto zone and had no codes.. So I then pulled the maf and cleaned it. Still no change..So then I pulled the plugs which look original and changed them along with new wires. Still no change! So whats my next step? Coil packs?? Is their a way to test them? Anyone have this problem?

 

[Thumper8302]

as far as the coil pack testing goes u can take them up to autozone and they will check them for free.... kinda funny how no codes were stored in memory. kinda makes me wonder if ur tranny is starting to have issues.. hope u find the problem man

 

[fire730]

Usually a flashing CEL means that catalytic converter damage is likely to occur. Usually a misfire causing raw fuel to be dumped into the converter. As far as pinpointing which one it is hard to find out which one until the computer tells you which cylinder is causing it.

 

[sumo]

Usually a flashing CEL means that catalytic converter damage is likely to occur. Usually a misfire causing raw fuel to be dumped into the converter. As far as pinpointing which one it is hard to find out which one until the computer tells you which cylinder is causing it.

exactly. But its not Likely, its Means it is.

 

[SunlitComet]

A flashing CEL is a active misfire and a scanner with enhanced gm diagnostics can tell you the misfire history of each cylinder to pinpoint which cylinder(s) is given you the problems. Look for stored codes as well not just active one. It should be address ASAP as it could not be just a malfunctioning injector that is putting out no fuel but also could be a no spark issue where raw fuel gets dumped into the converter causing it to overheat and melt the substrate but also washing down the cylinder wall.

---------- Post added at 09:55 PM ---------- Previous post was at 09:54 PM ----------

BTW Justin,

 

[Justin509]

So for the last day I have been trying to figure out what the problem is. I pulled the tb off and cleaned it. It looks like it has never been touched! But still no help. Also is their a way to test the maf sensor? I'm also thinking that it could be and injector but I am not sure which one since I have no codes. I'm picking up a scanner today and will see if any have been stored. I'm hoping that one is in their and will tell me whats going on.
Before



After





---------- Post added at 10:20 AM ---------- Previous post was at 10:15 AM ----------

Also here is a shot of the old plugs.

 

[fire730]

Usually the MAF will set a code.

You can eat off your TB now. But a dirty TB wouldn't cause a stumble anywhere over idle speed.

Those plugs were definitely wiped out.

What did you replace them with?

 

[SunlitComet]

1. yeah that is 205k miles on that tb.
2. Those plugs are beyond gone. Are they not supposed to be platinum type?
3. the scanner will either read back the output voltage or Air poundage that the Maf sees.

 

[fire730]

I thought that all the 5.3s used platinum plugs. He definitely wore off the platinum on those babies.

 

[SunlitComet]

those do not look like platinum's at all. The look to straight solid core to me.