I just got done swaping carb-tpi and im trying to figure out why my car spark knocks loud if i step on it a little from idle but wont do it after that. i figured its either the timing off(i know its not right and i forgot how to set it with the TPI cars) also if its not that, i noticed the drivers side rear 2 injectors seem like there not pulsing. i know all the rest are, it feels like the 2 are but not nearly has much as the other 6..... anyone have any ideas about this?

 

Best to test the injectors. As for the timing, that could very well be it as the ecu will dump timing rapidly in order to stop knock. Base is set by disconnecting the est wire and setting the timing, then re-connect the est wire.

 

Did you swap knock sensors with the correct one??? Have you datalogged the car yet???? Is this just an audible ping you hear?? How much timing do you have and what bin are you running???

 

Yes i bought a new one for it

no
Yes, its loud

Bin?

 

What ECM are you running??? And did you get the correct knock sensor for the ECM??? There are two different types for a 350 depending on the ECM itself. Did you have a custom chip made by someone or are you running the stock calibration??If you are not sure it would be helpful to know. If you pull your ECM and open the inspection cover you will find your chip. It will be with the memcal covered in a blue plastic housing. Remove it from the ECM and then remove the blue cover. Your chip will be right there. It will have a silver sticker with 4 letters stamped on it in capital letters. IE :APYU,ARAP,ect. Also what is the base timing set at?? Maybe doulbe check that its 6 degrees and refer to Red Devils comment on the EST wire. Its too bad you can't datalog a bit. That way you could see how much timing is being introduced and how much timing is being removed by the ECM fom the knock retard.

 

the whole setup is from an 87 iroc z with a 305 5-speed. the prom was done by john M. @LT1intake.com as for the knock sensor, i purchased a knock sensor for an 87 camaro with a TPI 305 so i am guessing it is the correct one since it is for the same vehicle. but i didnt set the timing so i think it is way off, but i am not sure on the EST wire, is that the connector in the harness by the firewill that is just 1 wire. i looked up a long time ago how to do it but forgot. and as for datalogging, i dont know what i would use to do it. but i went to go out and start it to set the timing earlier, and it wouldnt start, so i checked all the plugs and cleaned them cause i had problem where tons of fuel was dumped into the engine, but i cleaned them then checked for spark and there was none, so i checked power to the coil and there was, so i changed the coil(i had a spare one) and it started up, but it would idle up and down from like 1500 down to 700 and would almost stall then pick back up, if its my TPS sensor thats bad, id be pissed....lol but i need to get it running good before i can go set the timing.

 

If an injector isn't pulseing , you will know it . I had a bad one and, the car would barelly hold an idle . I was told this was because it's a batchfire setup. There is a tool called a "pulse tester " . It's a must have ....it tests the mechanicalls of the injector.


Good luck to ya man !

 

i knew about the batch fire but it feels like either there not pulsing or just not as much as the rest are. its very weird.... almost like a weaker pulse than the rest. but i dont know, maybe because its the closest to the FPR lol