Gm TBI Unit swap

had a 95 350 suburban with a crisp TBI unit from a fire. Had a older 350 TBI unit from a 89 or so. I bolted on fine electrical on the side were fine. The color or wires were different
from the TBI solenoids (had to splice the wires in) put it in and it seems to start and run
how interchangeable are the GM TBI units between years?
bob
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Well, if my translation of your language is correct, then it *seems* to be *fine*.
You say: "seems to start and run" which makes no sense, either it starts and runs, or it doesn't start and run. It cannot 'seem' to start and run.
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On 10/9/2010 7:55 AM, PeterD wrote:

Seems to start and runs translates into we threw the 89 TBI on the 95 and it started up . ran rough and then we changed the MAF sensor? ran much better, but still missing some. got dark and we quit. truck was NOT driven. the other TBI bolted right on, all the mechanical fittings were the same. The colors of the wires on the TBI solenoids was different. the 95 had an engine fire on the TBI, so it was crisp. We butt spliced the solenoid wires from the 89 on to what was left of the 95's harness. Hooked light colors to light, and dark to dark. The wire colors were NOT the same. I don't know if these have a polarity issue of not. Thats why i am asking questions.
Truck seems to been running well enough that the other issues could be simple plugs/wires and such. But it concerned me when the wires from the solenoids were not the same colors. I know swapping 4l60 trannies from that ears can be a treat because they changed little things in them over the years that can cause issues. I just did not know if they changed the TBI units somehow.
bob
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By TBI unit I assume you really mean "throttle body" (the TB in TBI) and by "solenoid" I assume you mean fuel injectors (which are high speed solenoid actuated valves"
I don't think it had a MAF as IIRC all TBI systems were speed-density based using a MAP sensor.
TBI unit or TBI system refers to the whole shebang AKA everything from the in tank fuel pump to the the ECM to the sensors and throttle body itself.
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bob u wrote:

Yes they changed the Throttle boddies some between those years. BUT the changes are not something to worry about. The wire colors are not a real problem either. The injectors are nothing more than a simple solenoid valve. No polarity issues as long as they are not shorted out.
You likely changed the MAP sensor as none of the TBI systems GM had uses MAF.
Misses on an engine that had a fire are probably related to wiring faults or vacuum lines that are leaking. Could even be intake gaskets if it got hot enough.
--
Steve W.

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On 10/10/2010 11:53 AM, Steve W. wrote:

Thanks for the reply. the engine idles good now. seems to rev at stop we took it for a drive today and it is chugging under load like its fuel starved. Will see if we can find a pressure gauge and see what the Fuel pressure is. Should be 10/15 PSI?
we took the MAP sensor off the 89 and put it on the 95. the 95's looked like it got hot.
bob
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