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HELP! Engine runs awful after mods and EVAP delete
Ok, normally i dont come crying for help but im in trouble with this one. I put billet rails, repaired broken pcv hoses, ran 8an fuel feed, used old feed as return and removed the entire evap system. The car loads up on gas and wont idle and i have range codes for maf, map and tps. I tested the wiring and what i could on the sensors and im lost. I removed the intake again to make sure i didnt punch any wires or forget to plug something up and everything appears fine. Im concerned that maybe removing the fuel tank pressure sensor, the purge valve and the canister may be to blame but i have never seen removal of evap affect the way an engine runs. Months ago i removed the air injection and the converters and never changed how the car runs. Is there anyone else that has had this problem?
Not sure if it helps but my mods are cats removed, hawks airbox lid, aeromotive 340, racetronix hotwire kit, billet fuel rails, 8an fuel feed, factory fuel feed turned into return, all evap removed.
I dont believe so, if i remember correctly it was stuck at 29.6. Correct me if im wrong but that would indicate a possible short to power on the signal wire right?
I dont believe so, if i remember correctly it was stuck at 29.6. Correct me if im wrong but that would indicate a possible short to power on the signal wire right?
If that reading is stuck & not changing I would start there. Not sure what the problem is but prob. with wiring if you already replaced the sensor.
Best thing would be to get a schematic of wiring & start testing. Pretty sure a 3 wire sensor. Guessing one 12v, one ground, one signal. Good luck man.
Im pretty sure it doesnt get a 12v. I think the green/center wire is the signal and the other 2 are 5v and ground. Im having a hard time finding the info i need.
I mean where is everybody? Is this forum dead? Anyways with my scanner the map reads 92kpa with koeo and koer, at idle and at wot. If disconnected it reads 10 kpa, i need to know what it should read in all conditions and i cant find this info anywhere.
My scanner reads in psi so: atmospheric pressure, around sea level, is about 101kpa or 14.7psi. Give or take. When the engine is off, koeo, the map will read the atmospheric pressure where you are. This is your "0", zero. When you start the engine the reading should go down meaning a vacuum in your intake. Thinking of a stockish/mild cam also. The more nasty of a cam the less intake vacuum at idle. Put simply of coarse. When you go WOT, say with a load, driving, the closer to your zero reading the better.
So if the reading is the same koeo, koer, at idle & revving there is a problem there. I think you said you removed the intake again & did a good visual, no hole/leak in intake.
What I would do is get a DVOM, volt meter, & start testing the circuits on that sensor. See if you're getting the 5v reference & make sure you're getting the ground. I'm thinking wires may have gotten pinched in the back but just a guess. Visual inspections go a long way. Maybe try & trace the circuits as much as you can.
Not even knowing if this is your "main" problem, the MAP is not working right.
Im being as patient as i can, my car is dead and its my daily driver. Been having to hitch hike to work, been down for 5 days already. I do appreciate the help ive gotten but on other forums ive been on i would have several people replying by now.
I finally fixed the car! After pulling the intake for the third time i found a broken wire inside the map sensor connector. It was the black low reference pcm ground wire. It was hanging on by a single strand and the rubber insert on the connector was hiding the damage. I might actually get some sleep tonight! Thanks for the help.
05-30-2017, 12:00 AM
HELP! Engine runs awful after mods and EVAP delete 
