Drive by wire vs. drive by cable and tps
#1
Drive by wire vs. drive by cable and tps
Long story short the ecm I'm using came off a truck with a drive by wire setup. I'm using a drive by cable throttle body. The tps stays at 0 in efi live no matter what (even unplugged). The guy doing the tuning says it looks like there are no tps drivers in the ecm. I don't know too much about tuning, but could swapping throttle bodies be an issue? It seems to be all that is keeping my car from running. It idles but it's super lean. Fuel pressure is good. It idles fast (1200rpm or so) and falls on it's face when you open the throttle.
Thanks in advance.
Thanks in advance.
#4
11 Second Club
We all know DBC systems. They've just got a cable from the accelerator pedal to the TPS. Simple. One thing for the ECM to watch - just the TPS.
When we move to DBW, it usually uses some kind of twin-redundant sensors for safety. There's no physical link to the TPS anymore on DBW, so they double-up in case one side or the other fails. They have twin APPs (accel pedal position sensors) and the other is a dual-pot TPS on the throttle body. There will be an APP1, APP2, TPS1 and TPS2 (or something along these lines) in the DBW ECM vs. the DBC ECM for redundancy/failure protection.
If the ECM is looking for all four of those signals and it's only getting one (TPS1, most likely, because you've got a DBC throttle body on the engine)... it'll cause problems you may not be able to program out due to ECM internal design. You may just need to switch to an ECM from a DBC system to solve the problem most simply.
-R
When we move to DBW, it usually uses some kind of twin-redundant sensors for safety. There's no physical link to the TPS anymore on DBW, so they double-up in case one side or the other fails. They have twin APPs (accel pedal position sensors) and the other is a dual-pot TPS on the throttle body. There will be an APP1, APP2, TPS1 and TPS2 (or something along these lines) in the DBW ECM vs. the DBC ECM for redundancy/failure protection.
If the ECM is looking for all four of those signals and it's only getting one (TPS1, most likely, because you've got a DBC throttle body on the engine)... it'll cause problems you may not be able to program out due to ECM internal design. You may just need to switch to an ECM from a DBC system to solve the problem most simply.
-R
#5
Okay, thanks for the complete answer. This is what I bought - http://cgi.ebay.com/ebaymotors/LS1-L...Q5fAccessories
I emailed him the other day and he said if I ship him the ecm he'll take a look at it make sure everything is there, and maybe with a little retuning it will work. If not I'll sell the ecm I have and pick up one I know for certain is dbc.
I emailed him the other day and he said if I ship him the ecm he'll take a look at it make sure everything is there, and maybe with a little retuning it will work. If not I'll sell the ecm I have and pick up one I know for certain is dbc.