Subaru Legacy, Running rich, idle problems

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I have a 91 Subaru Legacy Sedan L 5-Speed EJ22 Engine 140k.. Full synthetic oil every 3k, always!

When I start my Legacy, It idles fine.. 1,300 rmp's. then drops down to 700 rpm's when it reaches operating temp. Which is normal. The check engine light blinks a few times when I first accelerate but never seems to blink after first acceleration. When I push in my clutch, coming to a stop, the engine idles at 300 rpm's and jumps right back up to 700 after a few seconds of engine shaking. Its never died on me the few hundred miles I've driven it like this.. When stopped, sometimes it will drop back to 300 but jump right back to 700. Sometimes.. for a few minutes, the engine runs perfect, doesn't drop rmp's while stopping or stopped.. but will sure enough start right up again.
I cleaned the mass air flow, and sprayed carb cleaner multiple times down the iac valve intake tube.. not much of a difference.
Also been getting bad gas mileage, and fuel smells very rich

The CEL codes I got were:
16- Faulty #3 Injector
35- Faulty Purge valve
42- Abnormal idle switch voltage
49- Incorrect Mass air flow sensor

-These are all weird since I just replaced, the purge valve with a new part over 300 miles ago..
-All my injectors are in the right resistance range 11-12k ohms
-The idle switch did test faulty, but my car has been runnin fine for thousands of miles since I first tested it faulty. It could be the problem, but I'm doubting it. Its slightly low on resistance.
-And the MAF is deff the correct hitachi MAF sensor for the manual transmission. Its not throwing a faulty MAF code

I once put an automatic MAF on, only for a minute.. and the purge valve is new and shows the correct resistance, it seems as if they are old codes still in the ecu... but I've unpluged the battery many times for nights at a time.

Here's a list of the parts I have replaced, trying to fix this prob.

Ignition Wires
Ignition coil
Spark plugs
Fuel pump/strainer (because last time it was failing, sorta did the same thing but way worse.
Fuel Filter
oil change
 
What about your IACV? Bad VSS also causes some weird issues with these cars
 
Some codes will persist. A while back, I was swapping engines in the wife's 1995 Grand Am, so naturally I had the battery unhooked. After getting it running I was still able to retrieve all the ABS codes stored from a persistent problem.

11-12k ohms? As in 1000's??? That seems high to me. All the injectors I've ever checked have read in the high 7 to low 13 ohm range. Get a mechanic's stethoscope and listen to each of the injectors as the problem is happening. This may take a few attempts. Mentally log the sound of each, listening for "the odd man out" which by the sounds of it, is number 3. Good, properly functioning injectors will sound crisp and metallic through the mech stethoscope. Bad ones will usually either have no sound or a muted, muffled sound.

Also, if you have a scan tool that will give you live data, please post it up as this will aid in the diagnosis.
 
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Mass air meter codes can also be triggered by a vacuum leak somewhere in the manifold or intake system. Listen for loud whistling or sucking noises. The car is leaning out due to the extra air getting in past the MAF and trying to correct.
 
Originally Posted By: Audios
Mass air meter codes can also be triggered by a vacuum leak somewhere in the manifold or intake system. Listen for loud whistling or sucking noises. The car is leaning out due to the extra air getting in past the MAF and trying to correct.


A MAF code can also be triggered by an engine running near stall speed.

This is one reason why I suggested the o/p posting up some freeze frame data... Otherwise we could be chasing our tails.
 
Blinking CEL is never good; it indicates severe misfire. Usually it would be because of ignition system problems.

91 Legacy is too old for OBD-II and freeze frame data :-(
 
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