So long story short i pulled some codes and I would like some real knowledge to say something, or guide me in the right direction.

The codes that were pulled were:

P0100 - MAF or VAF circuit Malfunction
P0103 - Circuit High Input
P0300 - Random/Multiple Cylinder misfire detected.
P0412 - Secondary air injection system valve malfunction
P0420 - Cat. efficiency below threshold Bank 1
P1641 - FC Relay 1 Control Circuit
P1642 - FC Relay 2 Control Circuit

Alright, as far as the last 2 go (P1641, P1642) my fans were not turning on when the temp. reached an appropriate level, so i looked for some blown fuses and found some. I replaced that and that has solved the problem, at least it appears that it has.

I'm not really worried about the Air code (P0412); 1. it does not affect me driving the car and 2. i was planning on getting a mail order tune so i think that could be taken care of.

P0420 - Are my cats going bad again, they were replaced for the last inspection (2006) and it was a pretty penny. I would like to avoid replacing them again if possible. Is there a way to fool the computer into thinking it that everything is peachy? o2 sims? or mail order tune? maybe this way it will ignore it?

Now this brings me to the questions i really would like to get and answer for:

P0103, iresearched it on cz28 and it does not make sense to me. To quote a really smart man on here (Injuneer)

I have a CAI and i seriously doubt it that somehow it turned into 383ci engine and just sucked in so much air.. so ...

And the last but not least, P0100, seems to be like a common code, at least when i searched it it was. I do not have a multi meter or anything like that that i could trouble shoot with. Can the two above codes simply mean that my MAF is going bad?

In addition, after i deleted all the codes ( i was hoping they would go away) my car refused to run. It would fire up, and start but approximately 1 second after it would die. It did so for about 3 or 4 times. On the next try i tried giving it a little gas and it started just fine, however the P0100 came back right away. I tried to delete it again, and it still came back, but this time the car started normal and runs just like it always has in the past. I tried for the third time and i achieved the same result as i did in the previous try.

SO... If any of the smart folk on here have any possible solutions or hints do not hesitate to help me Too bad mail order tune can't fix everything

 

The P0412 AIR code is affecting your engine. It causes the fans to run all the time. And its not for the valve. It sets when the AIR pump is disconnected or the fuse it blown.

P0103 = MAF Sensor Circuit High Frequency. The code sets when the frequency of the flow signal out of the MAF sensor exceeds 10,700 Hz.

That could be the result of the P0100. That will set if you lose power to the MAF sensor. Key on, check for 12V volts between the pink wire and the black/white wires in the MAF harness connector.

Sims would eliminate the P0420 code for the cat efficiency. Harder to find them these days, since the Fed's shut down Casper's production and hit them with a big fine. You might just try switching the after-cat O2 sensors side to side. If the problem follows the sensor to the other side, its a sensor problem, not a cat problem.

 

Now that you mention it, I'm almost 100% sure that i have replaced that fuse in the past, and that's probably the reason it is not coming up anymore.

I haven't driven the car since August of 2007 so i have somewhat vague recollection.

Is there any other way to check if everything is ok, regarding the P0100. I do not have a volt meter hand here, i'm away at school and basically have nothing besides a few wrenches. But i will buy another one it if necessary, i guess.

Assuming i do not get 12V like I'm suppose to, what would the course of action be?

Thanks!

 

Anyone else have any idea what to do after i check for voltage? or if there's another way to do it?

 

Ok new question, HOW DO I USE A MULTI METER?

i know im stupid.... It has a lot of options and i dunno what to select and how to exactly perform this test...

I have this device

Is the *** suppose to be pointing to the "DCV"?




god i feel retarded...

 

Yes, you are testing DC voltage so you want the DCV setting. Did that meter come with an instruction manual, if so, do you still have it? I googled "how to use a multimeter" and came up with a ton of results, maybe read through some of the sites to get a better understanding of the different meter functions, electronic theory, ect. The multimeter is one of those tools that you will surely use again down the road.

 

yea, i googled and currently educating myself. i measured voltage of a AA battery kinda fun, i've never done it before even though i have one at home... ok back to reading.

Thanks for the help though.

 

Ok i finally did what you told me and i got a measurement of 11.22 volts between pink and black wire.

I also ran the car without a MAF and it ran the same, and no new codes popped up.


What should i do now?

Help, anyone?