rpm drop while driving
 

I'm having some issues after reinstalling my headers are being recoated, the 1st week went by with no problems. and then i get in to go somewhere and i get a SES light.

my car is listed in the sig below.

anyways, i didnt fell anything wrong with it until i went a little more than a few miles. I'll be crusing at around 2k rpm and it will suddenly drop 300 or so rpm and if i push the pedle down it does nothing until i let the gas off and then press it again. almost like its cutting the gas off, but the car is still running.

i thought it was the MAF but i swapped it out and still no difference. so i went back with my old one. i had autozone try to scan for codes but kept getting an error. might have to do with the fact that my car is a 97 and i have the OBD1 conversion, but i remember having it checked before with this pcm without the error.

i went and got new spark plugs but im going to check to see if the coil is putting out what it should before i put the plugs in.

if im driving down the road and i throw it in neutral i can hear the motor dropping and speeding up a little, like it doesnt know what rpm to run itself at.

what should i do or check? i've reset the pcm and unhooked the battery and the light keeps comming back. does it sound like im getting knock? i have the computer tuned to to make it less sensitive.

or does anyone1 in the youngstown area want to have a look at it in person? i dont want to take it to a shop cause i really cant afford to pay them to work on it, and i like to do everything myself.

thanks

Re: rpm drop while driving
 

have you scanned the computer to see what the code is? That is where to start. Do you have a stock knock sensor or an LT4 unit?

Re: rpm drop while driving
 

i had autozone do a scan but their tool wont pick it up, it gives an error. said its not a code that stays in the system, it comes on and off, i need to take it to a shop and have them do a real scan.

its startin to run really rough on me and im affraid to take it anywhere to get it looked at. although i wouldnt mind taking the motor out and apart and overhauling it with performance parts. as long as it would fix my problem.

ill have to wait til monday to have it checked, or i'll buy a lt1 scanmaster if it will do me any good.

also, i still have the stock sensor, my computer was tuned i believe to make the sensor less sensitive to read knock with my headers.

Re: rpm drop while driving
 

Check to make sure the O2 sensors are plugged in. It sounds like something was knocked loose or a plug forgotten about.

Re: rpm drop while driving
 

once the car cools down im going to lift it up and replace all the spark plugs, i got ac delcos from pep boys. their close to what came in the car, if not the origional ones. and im going to pick up some new 02 sensors, and but the extenders for them. i had my origonal 02 made longer by somebody my dad knew.

im going to lift it up and go over every inch to make sure everything is hooked up.

Re: rpm drop while driving
 

just work backwards. Thats the best thing to do in this case.

Re: rpm drop while driving
 

swapped out both O2 sensors and wires and still have the same problem. does it sound like the motor is picking up knock? my header may be hitting on my k-member. would that cause a problem?


when i start my can and let it idle, its really fast, almost 2k rpm at idle. something is wrong here. i'm going to take it to get checked. just dont know where