[97gtstang]

The cars been running rough, and the check engine light was flashing on and off while driving. Ill run for hours at idle with no problem, will not die while driving but noticable power loss and not smooth through the RPMs. Now I have a solid CEL. Pulled the codes today and only one came back

172: system lean (bank 1).

Didnt try to erase the codes to see if they were pre-existing. Yesterday I ran a can of seafoam through it: in the crankcase, Vaccum, and fuel tank. No big smoke show, but car seemed to run a little smoother. Replaced the fuel filter, air filter today and i think that helped. I cant hear it missing anymore. Wires look like they are in good condition, has 1 ford coilpack and the other is aftermarket. I did pull one plug, it was slightly white, thats a lean sign right? IDK if it was old damage or current. I unhooked the battery a bit ago to give the computer a chance to reset, but now its raining like crazy outside. I will try to pull codes again but does anyone know where to go from here if the code is still there? Also will it throw that code when idleing or do I have to get on it. If it will throw idleing I might go start it up now while its raining and see if it throws.

[akatagyourit]

Wish I had an answer. The 93 coupe i'm driving right now is throwing the same damn code, but the car runs like a champ. Lets see if anyone else answers. Would be something nice to get fixed to get that little extra mpg out of this motor.

[onefallenhero25]

Originally Posted by 97gtstang The cars been running rough, and the check engine light was flashing on and off while driving. Ill run for hours at idle with no problem, will not die while driving but noticable power loss and not smooth through the RPMs. Now I have a solid CEL. Pulled the codes today and only one came back 172: system lean (bank 1). Didnt try to erase the codes to see if they were pre-existing. Yesterday I ran a can of seafoam through it: in the crankcase, Vaccum, and fuel tank. No big smoke show, but car seemed to run a little smoother. Replaced the fuel filter, air filter today and i think that helped. I cant hear it missing anymore. Wires look like they are in good condition, has 1 ford coilpack and the other is aftermarket. I did pull one plug, it was slightly white, thats a lean sign right? IDK if it was old damage or current. I unhooked the battery a bit ago to give the computer a chance to reset, but now its raining like crazy outside. I will try to pull codes again but does anyone know where to go from here if the code is still there? Also will it throw that code when idleing or do I have to get on it. If it will throw idleing I might go start it up now while its raining and see if it throws.

hey there i am no expert but i had an 88 notch that did the same thing amoung other things but if you pulled on of the plugs and it was white then yes it means its to lean which means its getting to much or not enough air somehow or another. with mine it was in the vaccum lines so i would start with them and check to ensure they are good and no leaking. or could be something with the air box/air intake. i would check that also. well i hope my input helps and/or gives you some ideas to try. good luck

[akatagyourit]

White indicates a lean condition which is to much air or not enough gas. Not enough air would mean it would be pig rich and they would be burning a diff color iirc.

[97gtstang]

Should I replace the plugs or is there something else I should check first. The air filter was pretty dirty. Seemed like it was running smoother after I replaced the fuel filter too. I'm going to see if it throws the code tomm now that the battery has been disconected. I would check the air bow but there's a ton of different sensors and I'm not sure what they all do. I do know the speed density(?) sensor that's in the metal housing: the housing had some white powder inside it but I didn't have a tamper resistant Alan wrench to pull it out and check it. I'll Let you know what happens tomm morning

[97gtstang]

OK well this morning I put the battery back on and let it idle for 15 min or so to warm up. No code thrown, so I drove a mile or so to the carwash, letting the car rev up through the rpms. Washed the engine bay a bit and tried to pressure wash the radiator out since I saw some mud on the front bumper and didnt know if the previous owner had let mud get caked into the fins(it never overheated though so I dont think they did). Cranked right back up. Drove back again through the RPM range. No light, smooth power while accelerating. Let the car Idle again for another 20 minutes. Guess it was an old code? I do know that the vacuum line that goes from the intake to the valve cover could have a better connection, the vacuum from the cover is strong, but the fit with the vacuum line is horrible. Thanks for all the help guys, when I pull the plugs, if I see that they look really bad Ill prob ask some more questions.