street demon2k3

ive been having a lot of problems with my car lately, for one it has a bad miss when it goes into closed loop. thought it might be the 02's so i replaced them 3 times and rewired everything again to ECM, has new opti, plugs, wires, coil, and coolant temp sensor. the car runs without problems with the 02's disconnected, but plugs foul out in like 5-10 minutes. i thought it might related to the tuning, but yesterday i connected the 02's and the car died SES light came on. got a DTC33 high MAP, dont know what that is but could that be related to the miss. BTW my car is a 93 speeddensity, and has a new 355 with an LE2 cam and stock heads with minor work. any help is appreciated.

playa7970

how big is your cam? also describe what your experiencing because im sure im in the same boat as you i get the surge/miss around the 1000 to 2000 rpm range really annoying iv replaced everything known to man and its still there i know the issue is due to not enough vacuum at idle im getting about 7-8hg, have you check how much your getting as far as kpa?? i know anything over 67 and the pcm will freak out and come back with 33 MAP too high id like to solve this problem also... so hopefully someone will chime in so we can get rid of this problem im starting to wonder if it is the cam but many people are running bigger cams with no problems im stumped

street demon2k3

im running an LE2 cam 23x/23x and under 112 LSA. im having problems between 1k and 2500 rpm. if im just acceleration real slow it'll start to miss and pop through the exhaust. the car was running real good with the 02's unplugged, and then it started to miss again when i plugged them back in yesterday. the car is running a tune for an xe 230/236 and its driving me crazy already and at this point the car has just been a waste of money. been trying to track this down since may, and im thinking of selling it cuz its been parked at home for almost a year already. i love the damn car but im going to start school again in sept and i need a car to get there. please i need some help.

BTW: im looking for a way to datalog the car, im sure there is a cable that i need to buy as well as a program to make it work. anyone have more info on this, and how much did you spend to get everything together?

playa7970

tell me about it i got all this money in this car only to be disappointed.... i do really think its involved with the tune i should be gettin my tune from PCMFORLESS tommaro ill let you know how it goes as for the issue it is veryyyyyyy annoying to the point where i also want to sell it and give up but im in to deep now ill give it another 6 months if its not fixed then peace out Fbody...lol any funny thing is noone can figure it out, you can buy the cable for 90 bucks here http://www.akmcables.com and download datamaster for free and get 20 runs out of it here http://www.ttspowersystems.com/

Injuneer

You need to determine why you got DTC 33. Hook a vacuum gauge up to the manifold. If the vacuum is less than 10"Hg, you may be getting the code as a result of the code. If the vacuum is more than 10"Hg at idle, its more likely that you have a faulty MAP sensor.

MAP is critical to your speed-density 93, because the ECM can not calculate the mass air flow without knowing the density of the air, and MAP is one of the two things it uses to make that calculation.