Code 33 after 165 swap?
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Joined: Sep 2015
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Code 33 after 165 swap?
I did the 165 swap to my 85 using an 87 ecm. I started using a 89 bin tune with 6e definition then the tried the stock 87 bin with 32b definition file. I have 24lb injectors and this is corrected in the tune. Anyhow I checked tps voltage which is at .55V and no luck. I check all the pin outs and relay wiring like 10 times which all seem fine. The only thing that is on my mind is that im using two of the same 5 prong relays for the burn off and power, I think there both maf power relays, I don't know if this would make any difference. Code 33 comes on after 10 seconds of running, and it runs super rich. Mods to the car are: 85 corvette with 87 vette engine, headers, 24lb bosh3 injectors, adjustable FPR- I have checked the fuel psi, extruded runners and a tpis big mouth intake, the IAT is also relocated.
Last edited by 81 Sport Coupe; Nov 2, 2017 at 12:36 AM.
Melting Slicks
Joined: Aug 2003
Posts: 3,393
Likes: 392
From: Lakeville MI
It is likely that the burn-off is active while the engine is running.
Check the wiring on the (5-pin) burn-off relay that you are using. I think it will work if you use pin E. Pin D should be open. If bat voltage is on pin D instead, burn-off will be active and the maf will be powered all of the time unless the burn-off relay is activated. If this is the case, it may have already burned out the hot wire, so check the maf as well.
Also could be an open circuit on B12, or excessive flow, but check relay wiring first.
http://www.batee.com/corvette/codes/33a.jpg
Check the wiring on the (5-pin) burn-off relay that you are using. I think it will work if you use pin E. Pin D should be open. If bat voltage is on pin D instead, burn-off will be active and the maf will be powered all of the time unless the burn-off relay is activated. If this is the case, it may have already burned out the hot wire, so check the maf as well.
Also could be an open circuit on B12, or excessive flow, but check relay wiring first.
http://www.batee.com/corvette/codes/33a.jpg
Last edited by tequilaboy; Nov 2, 2017 at 03:14 AM.
Race Director
Joined: Apr 2002
Posts: 10,036
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From: Anaheim CA
The MAF signal wire goes to a pull-up resistor (tied to 5 volts). If the signal is interrupted for any reason, the voltage on the signal wire will go to 5 volts and stay there. Possible causes are corroded connector pins or other poor connection (or MAF connector unplugged) or a broken wire.
What is the TPS voltage at idle (the engine does not have to be running to check this)? It should be 0.54 volts +/- 0.05 volts.
What is the TPS voltage at idle (the engine does not have to be running to check this)? It should be 0.54 volts +/- 0.05 volts.
