I have a 99 Isuzu rodeo V6 with about 90000 on it. My problems started with an EGR code P0401 Insufficient flow. My check engine light came on and I cleaned the EGR as listed in the forum. After that the car idled very low and would cut off on me occasionally when on idle. I ran diagnostics again and got P0102 MAF code, P0171 & P0174 System too lean, and a P0303 Cylinder 3 misfire. My EGR code was gone. I was wondering if anyone had a any opinions to this problem. I will check the MAF tomorrow. Some people said it may be Gaskets, some say MAF is faulty, some say wires connecting to the PCM some say EGR is open.. Let me know if you have any experience with this.. Thanks.

Did you take a look at the #3 plug?

Not yet, I was hoping I just got the Cylinder 3 misfire detected code because my car idled out. I do need to change the plugs and wires. I'm thinking EGR , MAF, and Cylinder codes are all related.

Thanks for the reply..

did you clean the egr pipe too?

a misfire code can be caused by a bad intake manifold gasket (the first time mine was replaced it was tossing a misfire code).

I wasn't really sure about cleaning the EGR pipe. The instructions I saw in the FAQ's didn't go into detail about what to remove other than the EGR itself. I am a newbie so I didn't want to start taking off big parts until I was sure I had what was needed to reinstall them. Could the EGR problem cause the MAF code to appear?

OK.. Thanks for the help guys.. I just got my car back from the shop.. The problem was the intake manifold gasket. Both sides were cracked and splitting.. Changed out the plugs, replaced the gaskets, cleaned out the egr.. She's good to go with no CEL.. Now I have to work out a few electrical issues.. :banghead: