dyno problem

[sohc99gt]

so a couple of you may have read my post a lil while back where i was having issues with my car turning off after longtubes, turns out i just needed a dyno tune but when i was at the dyno shop i got something that even the guys said had never seen before. i have changed fuel filter, put accel coils and new spark plugs. they said maybe the alternator any one was going bad . at aroudn 3500 hundred rpm the power drops way down. and you can also feel it on the road it feels like if i hit a rev limiter and cuts fuel or spark. it did it with and before the tune. i just dont want to pay them 100 dollars an hour in labor for them to find out wuts wrong with it . any ideas
http://s39.photobucket.com/albums/e177/gt1990mustang50/?action=view&current=IMG00349-20090731-1516-1.jpg

[Nino]

Does your car have an auto tranny?

-Nino

[sohc99gt]

no its a 5 speed

[Nino]

I noticed it actually dips twice. Could it be a slipping clutch? Notice any odor?

[TorchRed04GT]

Thats weird man, I would check the plugs, injectors, and fuel pump. It could be clutch related also, maybe a galzed flywheel or something. If the clutch is slipping you will smell it burning.

[sohc99gt]

well i dont think its the clutch the guys at the shop would have noticed, plus it has a resurfaced flywheel and stage 2 ram clutch and no odor.. im gonna go get my injectors checked and i guess replace the fuel pump its seems to be happening more often now at wot :crying:.. o quick idea could it be a bad knock sensor?

[Nino]

Have you checked the PCM with an OBDII reader to see if it's throwing any codes?

-Nino

[sohc99gt]

yea i pulled it with my sct and no codes at all , changed plugs new coils, 93 octane gas and same stuff.. im frustrated of changing parts and spending money i could be using on something else so im just gonna go take it to the shop.. ill let ya know wut it turns out .. thanx for all the tips though

[Nino]

Yeah it does suck. Good luck man. I hope it's a loose wire or something easy to fix.

[92lxcoupe]

Check your Fuel Pressure before you have them go any further.