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Idle problems with a new mas

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20+ Year Contributor
Jul 20, 2002
Harrisburg, Pennsylvania
Last night my friend put in my 2G mas, new intake, and K&N FIPK. After everything was on and done, we took it for a spin and it was awesome. So on my way home I notice some idle problems as I come to a stop. I keep driving to avoid having to stop because I'm praying my car doesn't die. Once I read the firehall in my town the car dies. Now heres where we're stuck. All the vacuum lines and everything are fine. The ignition components are fine. Once I turn the car on it will idle at like 500 and almost stall and it will do that for about 30 seconds then it stalls out. Anyone have any idea on what the problem is? Thanks
It was always my understanding that you either needed to tune your car if you put a 2G MAS on a 1G or put in 550s

Did you just slap the 2g MAF on there or do you have a safc, you can compensate for the 2g MAF if you put 550's on without fuel managment, if you just put the MAF on and dont have anything to control it or even out the parameters then you are going to run lean.
As they said you probably ran lean. You might have done serious damage this way....lets hope not.

What you need to do first is take the 2g maf off till you can correct the fuel. Then you need to pull your plugs and see how hot they got and if you melted them. Look into your cylinders and see if you can see little bits of melted metal or any signs of melting on the cylinders. Do a compression test...pray you didn't melt a piston.

If everything looks good put the 1g maf back on and replace the plugs. AFTER you do this try and fire it up again.

Moral of the story is....when you have a problem don't keep driving making the problem worse. Also research before you change anything especially if it could mess with the fuel system.
Well I think the problem was fouled plugs and that my friend turned the idle down instead of up with the biss screw. I drove it home yesterday which is 2 miles from where it broke down and it drove okay even though I coasted the whole way. My car was running extremely rich before the 2G mas was installed so we believed it leaned out my A/F enough to make it better than before without being to lean.
If your car was running 20+% too rich before you have a major problem that you have to address.

Improperly installing a 2g mas without fuel addition is asking for it. Lets just say that for now because of the other problem you are running the right fuel mixture (maybe you have a boost leak). Some day you will forget about the 2g mas not matching the fuel and find the boost leak and fix it...but you don't correct for the 2g mas at that point.....

Walla you run really lean and melt the engine and can't figure out why. It is very important to have all things fixed before a mod and to make sure you do all mods correctly.
yea Once i did remove the tubes on my 1g MAF and the car was running lean and idle at 500 rpms I did one spin around and I decided that if i keep it like this I'll #### the engine and i had to put new stock MAF.Do not just swap MAF from 2G. Since im N/A the car felt better on higher rpms where N/A usualy run rich so it kinda compensate the extra air but still once i go below 3000 rpm the car started to hesitate.Im so glad that i run just one mile like that and didnt ####ed up my engine.;)
can I keep the 2G mas and get my S-AFC installed and then correct the problem? I'd like to keep the MAS because I already have the S-AFC waiting to be put in.
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