Hello folks, I'm at a bit of a loss right now. I have an 88 240 dl, automatic non-turbo. I was trying to get it ready for smog check(Ca. of course). Changed plugs, cap and rotor, cleaned the flame trap, replaced some hoses, and cleaned out the throttle body. I did notice that when I put the throttle body back on, it was idling higher, but I didn't think anything of it. Then I tried to set the timing, if I put it anywhere near 12btdc, it would develope a miss, and it would get some serious detonation coming up the hill to my home. It runs best around 6* after top dead center.. weird? The timing was weird when I got it a month ago, I was hoping the tune-up would help. So I got it all ready for smog check and realized it was idling prety fast. No tach so I didn't know how fast so I just took it in anyways. IT passed the emissions part of the test (barely) but the idle speed was too high (1250) and the timing is supposed to be at 12*BTDC, I had it around 6 ATDC.

At this point, I figured maybe the timing belt jumped a tooth. So I tore it apart and replaced the timing belt. Made sure all was lined up, put it all back together and it ran exactly the same. So now I'm at a loss. Any suggestions. I was scanning the forum and I found a post from back in 2008 about the IAC not working. I'm not sure where exactly that's located. Does anyone have a pic of it so I know what to look for. I think I might pull the throttle body off (now I think I might be calling this part by the wrong name) and just go through it again, that same thread said it might not be closing all the way. But that still doesn't explain the timing being so far off. When I adjusted the idle down by turning that screw under the throttle body thing, I could get ti to idle down, but when I advanced the timing, it would start to shake and miss then die.
Any suggestions folks? MY tags expired last month so I need to get this right quick before I get pulled over. I can't even register this car in my name till I get it smogged. I really don't need to get pulled over right now

 

the IAC is under the intake manifold and has two short bent rubber hoses about 1" outer diameter that connect to either side of the throttle body. it is a solenoid actuated air valve, that the ECU uses to control how much air the engine gets when the idle switch on the side of the throttle says the throttle is fully closed ...

if thats in California, pay the registration, and carry the receipt in case you get stopped, and they shouldn't ticket you. once its smogged, DMV will send you the sticker.

 

Ok, thanks. Sounds like that might be part of the problem. Good idea about paying first.