i really hate to post another code 33 question but i am stumped .i have a 88 iroc with a new scoggin dickey 350.the mass air is brand new from gm,both mass air/burn off relays are new.the tps is set at.59v,all ground wires are clean& tight,i have followed the flow chart exactly as required & all reading are as they should be.from a cold start it takes about 2-5 mins.for the code to set while driving i then clear the code with my scanner & it resets right away i do this 2 or 3 times & the code MAY not return for the rest of the day until another cold restart.i have monitered the green wire while driving & i never lose voltage on that circuit.all road testing has been done in town at no more than 30-40 mph.the burn off circuit is working properly & all related wiring is in very good condition.any ideas at all would be greatly appreciated.thanks

 

Swap in another 165 ECM and see if that helps. .54 VDC is supposed to be max on an adjustable TPS, have you tried lowering the voltage and or raising it a tad? Could also try swapping the burnoff and power relays and see if it continues.

I'm running one of their 350's also with an '85 TPI setup converted to the 165 ECM, no codes, no troubles. Everything is set to "factory" specs, TPS .52 VDC, Timing 6* BTDC, all new sensors.

 

THANK YOU for your reply morley,i have tried a good known ecm but the problem is still there

 

Try setting the TPS to .50 VDC and see if that helps, if not try .62, there is a "sweet spot" in the TPS it seems regarding the code 33. Another thing you could try is to see if you can lay hands on a MAF for a 1985 5.7/5.0 application (Vette, IROC or T/A) I am running my 85 MAF on my system that I converted to 165 ECM. The 85 MAF is supposedly a "pulsed" signal and this might be why I have never seen this code, the pulsing may correct a percieved voltage problem by the ECM.
If you were near me I'd loan ya mine for troubleshooting.

 

thank you morley,I will adjust the tps & try to locate a 85 maf for testing.