I've done the best I could searching s2ki and google, but couldn't find the solution so I will try asking my fellow s2ki members.

I just bought a pair of used MY 04 Injectors for my 2005. I swapped out some RC 550's from my Greddy Turbo and at first start up I throw a CEL, P1121 to be exact. Code translates to: throttle position lower than expected.

The car is pretty much stock, has intake, exhaust, and 255 walboro fuel pump.

The problem is that my TPS seems fine. My voltages are 0.35 at idle and 4.5 at WOT. At idle, car struggles to keep a steady idle. I took the car for a spin and it definitely feels like power is being limited. At idle when I rev and let go, the car almost stalls or actually stalls.

Has anyone ever had this problem or know what the problem could be?

 

Bump no one knows? Help a fellow S2KI member out. I'm dying here

 

Have you checked/cleaned the IACV (idle air control valve)? Maybe try that and a map whack and reset the ecu. Easy things to try.

 

So you used to have the Greddy turbo kit and now you've converted back to NA (plus intake, exhaust and fuel pump) along with MY04 injectors? Did this problem come up the minute you converted back to NA, or was it after awhile? Were you running those 550s on an NA engine before you decided to go to the MY04 injectors, and if so how long? I'm just a little confused from your post.

I actually had the p1121 CEL, but mine showed up after I installed my Greddy kit and emanage, which seems to be the opposite of your issue. I ended up solving my issue because of a wiring issue with my emanage harness. If your system is virtually stock and on the stock ECU though, I have no idea why you'd be getting that CEL. My guess is that is a wiring issue from when you removed emanage or whatever engine management you were using, potentially a bad groud somewhere.

 

Were those voltages taken at the sensor? There could be a problem between the sensor and the ECU (poor connection at the ECU, corrosion).

 

I've tried all of those, except cleaning the IACV.

 

Correct. And I got the code the minute I converted back to NA

 

Yeah, those voltages were taken at the sensor. I will double check for poor connections and corrosion, etc.



Thanks for the input guys. I will try all of these out.

 

All connections are solid, no corrosion. I ordered a new TPS, hopefully this will solve the problem. Anyone else have any suggestions???

 

Put the new tps in. I knew it was the injectors. The guy gave me bad injectors.