Hi, I have an 87 Golf with a 1.8 SOHC, that had been built about 6 years ago. Im not sure exactly what all they did to it, as I was not the owner then, but I think they did some head work, camshaft, bored, header, etc. The car is really strong, probably pulls 3 times harder than my buddies Jetta 1.8, and that's with it not running correctly. Before I purchased the car, it ran really strong and good, but the last time the guy drove it, he said it was nearly impossible to start, and then he parked it for about 7 or 8 months. I got the car at a deal, because I was kin to him (300 bucks!) and took it home. The car, once you got it started would run ok at low rpm, but if you tried to floor it, it would bog, spit and sputter. First I tuned it up, cap, wires, button, plugs, fuel filter, mahle (I think) oil filter, and fresh oil. I replaced the oil switches also. Well, after all that, it was still impossible to start sometimes, hot or cold, and still had the bog and miss under full throttle, so I switched out the fuel distributor, and again, and again...LOL. OK, the 3rd one seems to be working, as it does make a difference to the idle when you turn the 3 mil allen screw on the flap that contacts the fuel distributor plunger, but no matter how I adjust it, it still has that full throttle bog/miss. I pulled some injectors from 2 different cars at Pull-A-Part, and cleaned them up, inspected the o-rings, and blew air through them, and replaced mine with the best of the ones I had, and it didnt make much difference. Heres what i'm dealing with....The car has no O2 sensor, which I have heard causes it to fuel the car more, and when I plug up the fuel differential pressure regulator on the air box, right beside the fuel distributor, it buzzes VERY loudly, and has done so on all 3 fuel distributors, as I have been changing out the entire air box top, instead of removing the fuel distributors, and for the life of me, I can NOT get the car to run worth a S#*T with that differential pressure regulator plugged up. Even though the bog and miss is still there under full throttle, it is not NEARLY as bad as when the regulator is plugged up. When its plugged up, it will barely run over 1/3rd throttle, with it unplugged, I can get it about 3/4 throttle before it starts missing. My buddies Jetta regulator DOES NOT make this buzzing sound, and his runs fine, but is stock. has anyone got any ideas on this thing? Ive heard that the 02 sensor isnt a problem being unplugged, as the car ran fine and hard for 5 years, but everyone says the differentil pressure regulator should be plugged up, but it was also unplugged when I got the car, and again, it had been running fine. Is that true, or is this another thing that has been done (unplugging it) to give it more power? Also, the air/fuel screw on the intake, below the throttle linkage, facing the front of the car (NOT THE stop screw that is set to keep the throttle flap valve from closing too much), is there a "beginning" or standard setting on this? In other words, I run it all the way in, and then back it out ??? many turns, and then adjust the fuel distributor from there?