Do I have to change the ECM and the harness in my '88 GTA if i wanted to eliminate the Cold Start Valve, or can I just replace the chip with an '89?
Thanks

 

I have an 87 with the cold start injector unpluged works fine.The cold start injector is not controled by the computer in any way.It is control by a temp switch in the coolant.

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87GTA,350,Auto,MAF screens removed,K&N,modified air intake,ADSchip,3:73s,3inch cat back Flowmaster,TPS.54,Bosch Plat plugs,base timing 6BTDC,Bilstiens in the rear....,don't let yer meat loaf

 

Not controlled by the ECM?? Put the crack pipe down and get your facts straight. Ever seen a wiring harness schematic?

The cold-start injector is managed by the ECM, look around on www.diy-efi.org/gmecm/ and dig thru the source code to broadcast code BUA ('86 Y-body, same ECM as your application) if you want to see how.

Eliminating the cold-start inj is as simple as upgrading to '89 software. I swapped the harness & TPI system from an '88 GTA into my '82 Z28 and did this exact procedure, burned a chip with ARAP software (see the PROM board) and disconnected the cold-start inj. I later bought a plug kit (Summit Racing) and removed the injector completely to make valve cover removal easier.

-Kevin

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1982 Z-28

See http://www.mycar.net/mafb/registry/detail.cfm?id=276 for details

 

hmmmm i guess all that Gm tech training was fer nuttin


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87GTA,350,Auto,MAF screens removed,K&N,modified air intake,ADSchip,3:73s,3inch cat back Flowmaster,TPS.54,Bosch Plat plugs,base timing 6BTDC,Bilstiens in the rear....,don't let yer meat loaf

 

You had better lay off the crack and LOOK at a schematic closer. The cold start injector is controlled only be the coolent switch above the water pump, that's all! No ECM!
The 89 bin has additional fuel programming built in because they quite using the old cold start system.
John


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86 Camaro Sport
383 Speed-O-Motive Crate Engine, Trick Flow Heads, 58mm Accel TB, 3.73 Auburn Pro, SLP Cold Air Induction and Headers, Dynomax Cat-back, Serpentine belt setup.

 

My '87 camaro shop manual clearly states that the coldstart valve is NOT ECM controlled. It gets its power from the cranking circuit, has its own sensor, and is completely isolated electrically from the ECM, aside from the power rails.

Now, would its presence be felt by the ECM? Of course. Anything that dumps fuel into the intake is something that the ECM will have to account for. So I can understand that the BIN for a non-coldstart motor would be quite a bit different than for one with the coldstart valve. But to say that it is controlled directly by the ECM is false. Hell, they tell you to DISCONNECT the ECM in order to test the coldstart valve, that way you can get fuel from the valve alone, and no pulses from the injectors!

Now what I really have a hard time understanding is, why did it take them 5 years to realize that they don't NEED the coldstart circuit?! Just think of all the money they could have saved (or better yet, spent on useful F-body stuff) during the years they included it!

 

I have owned a 87z 305tpi,87 and 88 350 tpi GTa's ...all these cars i disconected the cold start DEFECTORS he he me thinks GM owns OIL STOCK...anywho ...the winters get very cold here and i've never experienced any starting or running problems what so ever...by the way,i'm a GM tech ...so eat my shorts<can i say that here

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87GTA,350,Auto,MAF screens removed,195 thermostat,cold start injector UNPLUGED,K&N,modified air intake,ADSchip,3:73s,3inch cat back Flowmaster,TPS.54,Bosch Plat plugs,base timing 6BTDC,Bilstiens in the rear....,don't let yer meat loaf

[This message has been edited by RP1987GTA (edited October 13, 2000).]

[This message has been edited by RP1987GTA (edited October 13, 2000).]

 

Kevnic
Hey man....what's the part number for that plug kit....does it include a plug for the valve or is it just for the fuel rail?
thanks


I later bought a plug kit (Summit Racing) and removed the injector completely to make valve cover removal easier.