More problems with Mystic Cobra

[scothew_gt]

Alot of you remember me haveing alot of problems with my '96 Mystic. You can see my origional post HERE. short recap, I was having an intermitent missing problem at low RPM, usually under 2k RPM under a load. It would also miss severly over 5500 RPM. Well today i changed spark plugs again and the low rpm miss seems to be gone. I previously had NGK tr-55's and I put in some autolite platmiums (only plug I could find available this morning)

I have replaced the wires, plugs, and coil packs. Also removed my C&L 80mm MAF. I run nothing but 93 octane. Today I ran it on the Dyno just to see what it would do and to see if i have any more problems. It seems that after 4k rpm, the car seriously starts missing and after 5900, the computer totaly leans it out and cuts timing. I only made 1 run so i will post the actual graph from it and also one i smoothed out a lil bit to make easier to read. If anyone needs the a/f I can do one of that as well.

I am guessing maybe I have an injector or my fuel pump going out. Anyone else got any ideas???

Thanks!
Scott

edit: here's the video of the run. Right click and save as

Power and TRQ curves
http://www.vibezaudio.com/scothew/cars/mustang/mystic/dyno1.jpg

Power and A/F
http://www.vibezaudio.com/scothew/cars/mustang/mystic/dyno3.jpg

 

[1 BA SVT]

i didn't see where you said you changed the fuel filter, when was the last time you did that?

 

[scothew_gt]

oops... my bad.. yeah i have changed the fuel filter in december when it first started missing. I have also ran a couple of different fuel treatment stuff through it. Lucas, Marvelous Mystery oil, and the GumOut stuff..

 

[1 BA SVT]

have you taken it anywhere to have codes pulled from it. when it was on the dyno did it spark knock any or just start missing?

 

[scothew_gt]

It has been missing for awhile now.. Today was just the day i was able to get it dyno'd.. We think its more of a computer pulling timing more than anything ignition wise. Most people are telling me its more to do with the fuel pump or an injector going bad.

its not throwing any codes that I am aware of. The only time it did put the check engine light on, Was when I had my C&L on and it gave code p0174 - system bank 2 lean. I took the C&L off and it hasnt done it since.