Digital Tuning 95 Stang Codes Koeo (511) , Cm (157, 212), Keor (159) Bad Mass Air Meter?

Discussion in '1994 - 1995 Specific Tech' started by 393strokervert, Apr 28, 2012.

  1. Hey guys, I'm getting these codes >>> KOEO (511) , CM (157, 212), KEOR (159)
    Iirc, the 511 code is because I have a SCT chip. MY car is a 95 GT, 5spd, 393 stroker, no egr, no smog (both turned off with the chip. Trick Flow 351 upper/lower intake, TF Stage-1 cam, 80mm TB, PRO-M 80 massair meter cal'd for the 30# injectors. The SCT chip is a mail order ship from JMS. The car ran awesome for a week or two after I installed the new chip... then started acting up & has gotten progressively worse over the past 6months (It's a weekend car so I don't drive it much). Cold start up is extremely rich, 10-11 on my wide band, surges really bad for 30 seconds or so, then smooths out, although still running very rich. After it warms up, it idles pretty good, A/F stays in the 14's, but if I try to run the A/C at idle/in town traffic, it will stall when I come to a stop. Low rpms/light throttle/parking lot driving, is really crappy... it surges/bucks at low speeds, ONLY when in gear, but if I'm just coasting, it idles fine.
    The other issue it has is when cruising 65mph+ in 5th under 2,200 rpms or so, for long periods of time, the A/F stays right at 14.7 +/- .02... then totally at random, it will momentarily go really lean (pegs the wife band @16.0 for a sec), cut's out, the comes back & is fine.... weird. I'ts totally random, like maybe once or twice in a 150+ mile round trip.
    Iirc, the "511" code is because of the chip. Idk what the 212 is from, I haven't touched the spout connector since I cleared the codes last, so I could drive it to see what new codes it would hold, that one beats me.
    Does the 157 & 159 sound like a bad mass air meter? I've had these issues for at least 6months now, but having gotten married this last year, life has changed alot from being single & my work schedule has changed as well so I haven't had the time to really mess with it, just drive it occasionally. A few months back, I was having these issues & I pulled the plug on the mass air to see if it changed any, it ran exactly the same, regardless if the mass air was plugged in or not. I cleared the codes after I did that & have been driving it here & there for the past couple months, so I could check the codes again. Any help or ideas would be appreciated. Thanks, Joe.
  2. Anyone have any info on those mass air codes?
  3. Have you gooled the code to see if there is more info on it?
  4. Yeah, I didn't find anything specific though, just generic stuff with no real answers on what those two mass air codes or the 212 code mean exactly. I did find that the 511 is normal because of the chip, which is what I thought I remembered it being, from what I had read on here in the past.
  5. 157 - mass air flow sensor fault, low voltage

    159 - mass air flow sensor fault, above or below normal

    212 - loss of ignition diagnostic monitor signal/spout circuit grounded

    Sent from my ADR6425LVW using Tapatalk 2
  6. Thanks. I know what mass air codes say, I just don't know if it means that my Pro-M is bad for sure, or if something else could be causing the codes... idk, I'm just tight on cash right now & don't want to buy another Pro-M if I don't have to.
  7. Do you have the stock maf or know anyone that could lend you there's to try? At least then you could see if it was still giving off the same codes.

    Also are you running an aftermarket distributor? I couldn't find much on code 212 either but I read on another site that it could be the pickup coil in the distributor. Take a look at this thread.

    from my ADR6425LVW using Tapatalk 2
    393strokervert likes this.
  8. Clear the codes, check the wiring and connection to the MAF very carefully. Make certain that the connector is fully seated and the pins are aligned. If you recently cleaned the MAF you might want to look at it as well. Using alcohol and a q-tip, if that's what you did, can damage the sensor element.
    393strokervert likes this.
  9. @chaos254 , Thanks for the link, that sounds logical. I'm pretty sure my distributor is a stock 351w from the 95 f-250 that my block came from, but it has a msd cap on it so I'll have to dig deeper on it & check it out. If it's the pick-up coil that's causing the 212 code, it is extremely intermittent when it malfunctions, as I only get that 1/2second cut-out that I mentioned, every now & then, & only while cruising... I'll def check out that pick-up coil for sure. I don't have a stock maf & I don't know anyone around here that has one I could test it with. Thanks for the info & input, I appreciate it alot.

    toyman, I did clean the maf a while back & I did do it very very lightly with the q-tip/alcohol method :-/ but that was a few weeks before I put the new chip in & it ran great with the new chip for a couple weeks, then started acting up. A few weeks back, I did check all the connections around the maf & made sure everything was good. I'll check everything & clear the codes again though, just for good measure. I cleared the codes this past Sat, then unplugged the maf & left it unplugged all weekend, while driving it. I drove it 250+ miles this weekend with the maf unplugged, & it didn't drive much different than it has been with the maf plugged in. It actually seemed to idle a little better & had a little more power with the maf unplugged actually & I got a little better fuel mileage with it unplugged as well (19mpg city/hwy combo, more hwy than city though...I've been getting around 16-17mpg). I'll plug it back it in, clear the codes, & check it again soon & see if I get the same codes again. Thanks for your input, it's much appreciated. Thanks.