Whenever I am accelerating up a hill on the highway the service engine light begins to flash and the car begins to bog down and get sluggish as soon as I am over the hill it's fine. The light still flashes tho. Until I turn the car off then it turns off and doesn't show. When the key is turned on just for the battery to come on it shows the light on the dash. I got a MAF code. I did all the plugs and wires a month or so back. Any ideas of what the could be? 2001 Chevy blazer LS 4wd 4.3L SFI 6cylinder

 

A flashing CEL means that the PCM is detecting multiple misfires.

Did the problem change at all (better or worse) after doing the plugs & wires?

Did you also replace the cap & rotor at the same time?

What brand of parts did you use?

 

Used AC Delco wires, and auto lite spark plugs. Didn't change the cap and rotor and yes the problem changed after plugs and wires. It's throwing a mass airflow code at me when engine is off with battery on. Other then that it resets and doesn't show anything.

 

What was the change after replacing the plugs and wires? Did it get better? Or get worse?

I'm not a fan of autolite plugs, especially in GM engines. This engine likes AC-Delco plugs, and no others. Yours should have had AC-Delco 41993 plugs in it from the factory. Those are Iridium plugs, and last 100K miles. If those are too rich for you, you can use AC-Delco R44LTS6 copper plugs. Either way, the gap should be 0.060".

For the wires, did you use the "exact fit," "original equipment" AC-Delco 746KK set? or the "professional" 9746KK set?

 

My bad.. I used duralast wires, the prob did get much better after replacing plugs and wires, car runs strong, just when I am going up steep grades and I need to accelerate it just drags.. Sluggish and slow.

 

Sounds like a PO30x misfire with the flashing SES light, but you say there is a MAF code?? How sure about that are you? Well, MAF codes are very low numbers like PO101, PO102 and you always fix those first.


If you had only a PO30x misfire code, based on what you have said I would suggest you do the following in this order (stop at #1 if that fixes your problem).


1. Replace cap and rotor - and check/set cam retard offset to 0° ± 2°.
2. If still not fixed, look at fuel pressure per sticky at the top of the second gen forum. Report all four values (no, testing pressure running at idle and associated pressure drop is not enough - do all the tests)