Just replaced the tired old '83 305 with GM 350 HO with Vortec heads, bought the custom GMPP vortec manifold with EGR and kept the old CC Q-Jet that was working fine (car ran 15.33 few months ago). due to the local emmissions requirements I have also retained all stock equipment except EFE (which is not required or checked for). the swap went relatively painless and the car runs good once it warms up, 1st problem... If the car is left at a idle for 30 seconds or more the check engine light will come on and I get the code: 21 (tps volts high) and 2nd, my choke light stays on all the time. I can unplug the choke and it will go almost off (really dim). I think it has something to do with the AIR pump diverter valve the solenoids will have power iniatially then they shut off, closing both valves which diverts the air to dump out the front and not go to the exhaust. Does Anyone have any ideas or past experiences that may help, I am all out and would appreciate any suggestions or mods that I may have missed during the swap.

SS
SSRacerhu@hotmail.com

 

Wow, a CC HO 350!

1st dumb question: Did you check the TPS voltage? Should be about 0.54 VDC warmed & idling.

The choke light is either a bad choke relay or fuse. Haven't had it happen to me personally, but it's been discussed on the carb and tech forums. It doesn't have anything to do with the A.I.R. diverter valve, though.

I assume your 15.33 was with the 305, correct? Any times with the 330 HP?

Just curious, did you plumb exhaust up to the EGR valve?

 

Thanks for the reply, I read some of your other responses to others and kind of had the feeling (or hope) that you may have some ideas. Yes, the 15.33 was with the 305, sure suprised few people, even after having a 1.02 R/T (I'll blame that on the clutch)it still had enough to pull out a win over a 72 Nova, the car has alway been very quick but with 140,000 miles on the old 305 "H" (HO) engine it was getting tough to keep the oil in the engine. what little oil didn't leak out was being sucked through the valve guides. adding a quart every two weeks was getting old.

I did check the TPS Voltage and it was around .72, book says that less than .7 is zero by the computer, does this just mean my idle adjustment is holding the throttle open a hair too much? or does the TPS need adjusting, I didn't want to pull the plug and start tweeking that unless that is really what needs adjustment.
I have not plumbed the exhaust to the EGR yet, I did use the V6 EGR valve suggested by GM but I'm not sure where the best place to tap into the exhaust is. I have gutted the EFE valve and had plans to tap in at that point, what do you think?

The reason I think the smog pump and the choke light are related is because when I broke a belt the choke light came on, and from the wiring diagram it looks like they (and several other sensors, like the Knock sensor) are all tied together.

Thanks again,