Engine Car Isnt Making Power Please Help

[asphaultcowboy82]

My motor is built but isn't making power and when I floor it the check engine light comes on but if I stop the car it goes back off and its running rich u can smell gas this motor should be pushing close to 400hp and its running like stock anyone have an idea what's wrong with it

 

[94blackcobra]

We are going to need more information to help you out. You say the motor was "built," but what has actually been done to it? We need specific details here. Your car will store the code for the CEL, so pull the code and see what it says. I am guessing it is an O2 sensor but pull the code to be sure. Finally, was your car properly tuned after it was "built?"

 

[asphaultcowboy82]

I bought it already built it has rpm alum heads ported,76mm maf,70mm tb,gt-40 tubed intake,30lb injectors,190lph feul pump,3:73 gear,fp regulator,comp cam 544 lift ,trw forged pistons,fluidyne radiator and 150 shot nos I can't even do a burnout its losing power bad ive heard it could be the o2 sensors or maf or temp sensor it won't beat a stock car it used to jump sideways in 3rd now its just weak idk I forgot the car has MAC shorty headers a off road h-pipe with prochamber and MAC flowpath mufflers has msd distributor and streetfire coil and Taylor 10mm wires,tko 500 trans, king cobra clutch,I'm probably leaving something out but its mildly built but it isn't running right at all it sounds like a beast I've spent a lot of money making it saleen clone

 

[DanG]

* Try cleaning your MAF filament wires with a Q-tip and either isopropyl rubbing alcohol or electronics parts cleaner. Be careful as to not damage the thin wires or get any cotton stuck on them.
* Have you tried pulling any codes? Obviously with a CEL, you're going to pull codes in the car.
* How's the timing look w/ a timing light on it?
* How do your spark plugs look? Change them recently? If so, gap?
* How many miles on the motor? If all of this started after a period of spirited driving with the nitrous system, you may want to try compression testing each cylinder and/or leakdown testing to see the health of the motor. I would however do the above mentioned first. JMO

 

[ProKiller]

have you verified the timing? was the car ever tuned or have a chip for the mods?

 

[asphaultcowboy82]

Thanks for the info I'm gonna pull codes Monday morning I just haven't had time to mess with it lately I'm fixing to put a dss racing 347 stroker kit and a hellion turbo kit with 10lbs of boost on the car I just wanna fix this problem before I start this project I think its my maf and a bad o2sensor that's but I'm gonna try cleaning the maf like someone above mentioned but I appreciate your help this site is awesome for gear heads like us.oh yeah does anyone know where a good used dart block is for sale maybe someone who started a build and lost interest if so let me know

 

[asphaultcowboy82]

Hey guys just wanted to let u know I pulled codes on my car today and the results were a faulty tps and a bad o2 sensor just wanted to let u know thanks for the help

 

[VibrantRedGT]

Replace both 02 sensors and get the TPS either adjusted or buy a new one. Set it at .98v key on. Clear the codes after this then see how it runs.

 

[from6to8]

Hey guys just wanted to let u know I pulled codes on my car today and the results were a faulty tps and a bad o2 sensor just wanted to let u know thanks for the help

let me know if u changed the tps, checked yours to see what volts it was set at or if it would even set within a good range or what? Did you get your codes via the koeo and koer tests and what codes did you get?

 

[Chad Hensley]

My motor is built but isn't making power and when I floor it the check engine light comes on but if I stop the car it goes back off and its running rich u can smell gas this motor should be pushing close to 400hp and its running like stock anyone have an idea what's wrong with it

My car did the exact same thing when I first bought it. It ran decent till about 3k rpms then if you floored it it would literally struggle to make it to 5k and the light would come on and off. Come to find out the MAF had never been cleaned in 120k miles. One side of it was built up with crusty carbon. I hit up advance auto for a can of MAF cleaner and 15 minutes later it was like a new motor. Made a amazing difference.