Just installed a tbi 305 in my 89 astro. Broke in the cam as required. However, first trip down the road was not so good. This thing seemed to run good in the driveway but going down the road it popped, farted and limped its way up to 45 mph. I have used all the original sensors from the 4.3 tbi. I have gotten conflicting answers on what sensors would swap over to the v8. I did replace the ECM with the correct year and equipment. Does anyone know for sure what sensors really will work on the 305. It seems like the engine retards itself when I get a load on it. Once its up to 45 mph and I let off on the gas it seems to smooth out. Any help would be greatly appreciated as my wife is getting upset with the amount of time I am currently spendy with "the van".
305 tbi first time out
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You didn't, by any chance use the 4.3 injectors? It sounds like it's having a fuel or timing issue...not much to go on, but a guess.
I used the 4.3 injectors that flow 45 lbs. instead of the 40 lbs. injectors for a 305. I do have a set of 5.7 injectors I could throw in if needed but I figured the 45 lbs were closer to what the 305 should be running. I'm leaning toward the possiblity of having some sensor issues or maybe ECM problems. I am running all the 4.3 sensors ie. ESC module and knock sensore, MAP, IAC, TPS, oil pressure and temp switch. I have replaced the ECM with one that should have been from a 89 chevy truck with a 305 but I am now having a hard time verifying the broadcast code. Do you know of any good sources to get a list? My ECM is a 1227747 with a broadcast code AKTM. I have called dealerships with no help and have looked high and low on the net for this AKTM, but nothing. Any help would be great.
[Rule 21 Violation] maybe Lockdoc or one of the V8 guru's will be able to answer you....
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