98roushgt2

It all started with a rough idle, idle would dip now and again during stops. I troubleshooted and cleaned my IAC, then I tried the EGR Valve, I noticed that by removing the hose to the EGR my cars idle remained steady and the problem was gone..It ran fine for a few days Now I notice that when I floor the car the RPM's jump the engine roars but I dont go any faster they just float at 4k and dont increase. Also, when im accelerating between 40-60 mph the car will sometimes hesitate/sputter once I get to about 80 it becomes smooth again. My fuel consumption has also increase and I have began developing more the usual amounts of carbon on my exhaust tips, sometimes I notice a tad bit of black smoke...however the oil is clean and pressure is perfect, so i think it prob burnning too much gas/rich. What could be the problem ?? Its a 98 GT Roush Stage II automatic(sad I know) 98k mil </P>


Help me please!</P>

CHARGED

Hi. I had a similiar problem with my GT. A rough idle at low RPM , and even on the go at midrange some hesitation and flat spots occur.</P>


But when im gunnin it past 3000rpm its perfectly fine.</P>


Im also running rich because my fuel consumption sucks and I also have plenty of carbon biuld up.</P>


My check engine light came on, so I yanked the code and it read Air flow signal voltage low.</P>


Thats the cause of a faulty mass air meter.</P>


My mechanic suggested that i upgrade my mass air since it seems like its f**ked to a PRO-M 80mm.</P>


So I think you should ckeck your mass air sensor and upgraded if it stock cause they restrict alot of air.</P>


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vfast

the sensor you can tap on with your finger if the idle changes your have found the problem..sensor is cheap on e-bay....reset your tps and put the vac line back on egr..this is why gas comsuption is up..as your 02's are having a problem with mixers...seems like the egr valve could be bad after reconnection it up pull of the battery cable and reset the computer then pull codes

CHARGED

Heres a pic of my DECH Mustang</P>


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2kpony

I have a 2000 GT vert and had similar problems with it.</P>


First do an OBD II code diagnostic check up. I suggest that you buy one of those OBDII scanners, they come handy and they are not expensive. I had a similar problem and the computer gave me two codes- (Idle air control speed malfunct and something else, I dont remember) . Doing some Web research I found some info regarding the IAC motors and EUREKA!.. I went to the dealership and bought a new one for $80 instead of cleaning it since I 've heard that when the IAC motor is damaged there's nothing much you can do about it, so cleaning itwon't help.I did the work myself and tadah!! , the car was new again, no more problems so far. Try this first, and the new IAC is easy to install, do all the work yourself and you'l save some money.Hope these helps.<IMG src=smileys/smiley14.gif border="0"></P>

vfast

man that pic sure helps him<img border="0" src=smileys/smiley17.gif border="0">