I bought an 01 blazer 4wd recently and have been slowly fixing it up. Already has cap, rotor, performance coil, performance wires, and new plugs. Ran great but i was only getting 13 mpg and could feel a miss at idle. So I decided to put a new fuel spider in it, and cleaned the maf sensor while i was at it.

Got everything together and had a bad vacuum leak, loosened the plenum and re tightened and it went away. It was running rough but I figured it had air in the lines and took it for a short drive to see if it would fix itself.

Now it runs even rougher and the ses light is on and flashing intermittently. I've looked everything over repeatedly and can't see anything wrong.

Any ideas, I really do not want to find out what the dealer is gonna charge for this.

 

any codes ?

 

everywhere was closed by the time i got it back together, I will go in the morning and check the codes

been looking around online. a lot of places are saying that a flashing ses is a severe misfire. Wondering if dousing the intake manifold with carb cleaner fouled the plugs. Used to do it to old 350's with out any issues, but the then they didn't have a hundred and one sensors hooked up to them.

 

it must be off timing you should have a code p0300

https://blazerforum.com/forum/diagno...4-5-6-a-35153/

any ways check for the codes and get back to us

 

how would the timing be off i didn't touch the distributor and it was fine before I took it apart

 

oh to remove the intake on an older model you need to remove it im sorry had a long day at work

 

no worries

 

I went and ran the codes got a cylinder one misfire and mas sensor codes. Went back 5 min later to get the code numbers and it had a p200 code but nothing else.

 

What did you clean the MAF with?? Also these intakes are critical to proper torque,, any grounds removed and replaced I have not done a spider yet,, Matty man

 

P0200 sets when the voltage for the fuel injectors is incorrect. This might be as simple as the connector for the injectors not being fully seated

also Check the 15AMP ECM1 fuse and the 175A BATTERY fuse

also ses light flashign means posiable cat damage if u keep driving it like that
could also be a bad computer shorting out the injector...

Possible causes for P0200 code are

Open or shorted injector
Injector low internal resistance (basically an injector that works, but is out of specs)
Grounded driver circuit
Open driver circuit
Driver circuit shorted to voltage
Wiring harness intermittently shorting against underhood components