Okay my second hand 91'RS 305 automatic T-tops was running great EXCEPT; 1 A mildly fast idle smooth but just about 200rpm fast 2 no heat, DEFROST air but no heat in the air and no ability to select a different air flow ....yes the vehicle is equiped with AC 3 engine cooling fan will not acctivate. 4 no dimmer switch at the turn signal lever 5Tachometer is irratic. ENOUGH FOR NOW so I have found some of these issues and resolve them only to create more different issues I think someone replaced the temp sensor switch and wraped it with teflon sealing tape which insulated the switch from the engine block and effectively from ground so that may be why it does not activate the cooling fan relay and turn on the engine's fan, not sure yet; in the interium I have grounded the lead from the temp sensor and this activates the fan it's a temporary fix very shade tree mechanic (STM fix ) not a repair. OKAY: now this is what I have done so far: replaced the radiator hoses and thermostat hot flushed the radiator and replaced all lubricants throughout vehicle including my personal stash of tequilla. aquired several relays from wrecking yard including a tach and heater/AC control. while looking at the control noticed that the vacuum selector fastener was missing it's clip ends .....THOUGHT this is a vacuum leak and could cause a mild increase in RPM........... put a screw in it and will replace the existing control ASAP. lowered the steering columne and removed the insturment panel replaced all the panel lamps and noticed mild copper oxidation on the printed circuit .. cleaned the oxidation with a pencil eraser and alcohol to a nice bright shine placed a small stripe of foam tape under the connector leads to insure a more direct contact when this is plugged back in. examined the tach discovered a that one of the pins was not inserted into its recepticle and corrected this. upon reassembly of the sterring columne the engine IDLES VERY ROUGH. although the tach is now functioning ?corrdectly? I am going back in today and see if I disconnected something ANY IDEA what to look for? I found a second ignition switch attached to the ORANGE security lead if I take the key out the vehicle will not start with the key in the vehicle starts but runs very rough? I understand some about the resistance of the individual key's chip. and that some people have attempted to disable this feature on their cars. is there a document that discribes this proceedure or is it compleatly STM fixed.

To my knowledge, the factory security system(VATS)will have nothing to with the engine running bad or causing a rough idle. The VATS system is a separet system and only identifies that the correct key is in the ignition and then tells the ecm to turn on the injectors and other things to start the car. There are ways to bypass the key and the whole system. Do a search on VATS bypass and you will find all kinds of info on how to do this. Your 2nd switch you talk about, will need to see a pic of it and the orange wire to see whats going on.

okay so this Vehicle Anti-Theft System (VATS) relays a resistance to the ecm allowing the ecm to pulse a signal to the starter and to the fuelinjectors CORRECT.......and your stating that this will not cause a rough Idle or stop the vehicle from starting all together?........ okay starter now turns and vehicle will not start...... I believe that is what I am stating is the problem.
however before when the vehicle started and idled perfectly before I found the extra KEY before I pulled the key out of it's separate ignition switch.to see what the hell it was and turned on the key on the column and saw for the first time the SECURITY light and was unable to activate the starter. I said OOPS I wonder what that is for????? and put the key back in the extra ignition switch and attempted to start the vehicle which it did but it then ran rough and would barely idle. NOW the starter will engage and turn quite well but the engine will not fire. sooooooo some %*^*^%^%$#*hole SHADE TREE MECHANIC BYPASSED THIS VAT system and now it is crapped out ......I have only owned this vehicle for a few days at this point and I am enjoying the funny puzzles people do to make things work instead of doing it correctly.
I will take your advice and research the VATS BYPASS methods I believe I will pull the entire wire harness out and rework it to suit my specific needs I think I'll blueprint it while I am at it so if I ever decide to re-sell this wonderful machine the next guy won't be so disgusted at what I did to the car.

okay so the other issues I put in a rebuilt heater\AC control head because the first one was causing a vacuum leak at the selector valve due to the fastener clips being broken off ( I put a small screw in between the clips jaws to pull it forward and seal the selector to it's other half worked very nicely) noticed that the ac switch had a burn spot on it's contact so I replaced that while I was at it .
I am going to install an Variable resistor in the tach's PCB to allow for a more accurate RPM reading and make it accessable by a small screw from the insturment panel just below the Tach I'll lable it an secure it in position with techseal next time I am at the B&G automotive in eugene oregon those guy allows like the little tricks I do to my vehicles as long as I tell them what it's for they will get a kick out of it.
I also found thet the brake light vacuum switch was not seated well and attempted a remedy for it by putting 2 small slices of heater hose front and rear of the electrical switch housing ......seems some &*%*&^%hole (STM) dropped the steering column instead of bracing it up when they were in there makeing mud pies out of the VATS so the brake light switching system need some work and since this is a vacuum over hydralic brake system I would not be surprized if there is a massive vacuum leak from that location as well no wonder they could not get this vehicle to run for very long........WELL I WILL
and maybe with a little help from you guys It will be sooner then latter.

Okay JER: your absolutly wrong: the VATS can cause the rough idle and disable the entire system. I have since resolved the issues I had with the VATS and now have moved on the other puzzles ........But thanks for your input you at least were reading and you did coment on my post so thank you for that. Oh for other members with similar issues with the VATS......be sure to follow the GM troublshooting flow chart it is posted by GM and is specific.
there are several ways that shade tree mechanics (STM) can disable the VATS all of them leave loose connections that can cause intermitant issues with idle and start so be aware if you buy a vehicle that has had the VATS tampered with you will be in for some ADVANCED ELECTRONIC TECHNICAL DIFFICULTY. and you may want to associate with a professional electronis technician. the isues with the key's resistor is simple enough but the sequence that the ecm must associate with the key's resistor to enable a correct read is very specific. BYPASS the KEY and you have a new set of issues this is all old news and there are lots of publications on this exact issue not all of them are informed. I FOUND MINE WITHOUT HELP BUT THEN I AM A CERTIFIED TECH CLASS III. I looked for days for an online wire diagram and GM publications and then actually got under the dash and diagramed what the previous owner had done determined why he had done it and then looked at the GM wire diagram and plotted my best method to resolve what his attempts were causeing while effectively enabling the VATS and restoring the system to full function. PICTURES did not help me they only caused distraction. there are so many faulty connection made in this old car that you really need to discover ways of creating absolute connections and wire tie the harnesses to the fire wall leave only enough lash to make the mechanical install be sure to look for burned wire discoloration when you open the harnesses and find out why don't just leave it ...........man this was frustrating, and I understand why it was in the condition I found it. NOW it is REPAIRED not FIXED if you want or need my consultation just ask I have photos and I am a willing associate but not unless you ask and we communicate directly NO FORUM

Okay I Have her running very nicely: everything works the way it's supposed to and tomoprrow I am going in and haveing the windshield replaced. Until I find a matching gary Camaro drivers seat that is about all I will be doing to her ....I installed my favorite am/fm/CD a clarion DXZ750 and the sounds are a nice background while driving around town ....I don't really love this camaro but it will be a good trade in when I am ready this spring by comparison I think I'll ask $3500.00 with a nice wax an shine. I was going to install a PC and monitor an trick her out but the car just does not merit that kind of accessory. too much time invested and I'll end up with a driveway anchor. oh did I mention the engine and tranny only have 27000 original miles on them because the original owner lost his key and had a shade tree mechanic bypass the VATS the car was never dependable enough to drive out of town so it sat in a back yard with a cover over it for almost 5 years by the first owner and then was sold to the second owner another shade tree mechanic that attempted another bypass and it sat in his driveway for another 3 years before his brother helped him get it started and it was still very undependable so it sat on the street most of the time until he posted it on Craigs list as a possible trade SOOOO i traded him a 94 ford explorer for her with the idea that I could get a better return on a muscle car then an SUV and looking at all the camaros posted for sale this is one of the middle better looking ones so far........