random hard starting

[38SHO]

ok so I got one for all you gurus out there

first off 1993 MTX...... every few times it is very hard to start.... I get it to start by giving it some gas, then it fires up but idles very rough, surging rythmically.... if u rev it up a little bit the surging goes away.... IAC? maybe


now just to keep the goons from throwing out the easy answers..... let me inform you of a few things

I've always had this problem since I've bought the car a year ago

since then, for whatever reason, these things are different or have been changed for new parts.......

Computer
Engine
Cam sensor
crank sensor
coil
dis
grounds
plugs
wires
engine wiring harness
fuel pump
fuel filter
FPR
Injectors


pretty much the only thing the same is the:

chassis wiring harnesses
IAC
TPS
MAF
Intake Manifold
o2 sensors
chassis fuel lines
CCRM


one time I scanned it and got a funny code, something to the tune of bad TPS voltage at idle..... I notice something funny, the stop screw on the TB is not there...... so I'm thinking that could be doing something... or I'm also thinking the IAC could be going out intermittently...... hence the surging, or the TPS is going out.... or a combination of all 3....... what really points me to the IAC is the surging and the fact that cracking open the throttle(engine recieving more air) helps it start.....

thoughts... opinions... laughter and snickering...... please chime in

I have a spare intake manifold I'm painting right now that had a functional TPS/IAC/TB with stop screw before Kelvin's accident..... so when I finish that I'm gonna slap it on the car.. this might cure it, might not.....

anyone run into something like this before?

I cannot recieve any datastream from my snapon scanner

 

[SHOtime2511]

make sure you have the ground good tight and in the proper place(s).
then id go ahead and pull the IAC and give it a good cleaning,remember that the valve is plastic so standard parts cleaner may damage it.some kind of electronic cleaner would be best.

 

[Vnuk1]

X2 on the IAC.

 

[38SHO]

I got another one here but I was just gonna put it on when the intake is finished... I guess I been slacking in that department......

changing the TB, IAC, TPS, and that stop screw at the right spot might fix it... then again it might not........

knowing my luck...........