Eternal_Gamer

iTrader: (10)

ECU Code 18 Trouble (Throttle Sensor - Narrow Range)

I am putting my car back to stock to smog, and I sucessfully put everything back. The car was idling fine and all, and as I start to move for a test drive, I all of a sudden get a CEL, and it doesn't want to idle anymore. I drive it around and it drives fine, but I get a CEL and it won't idle. I check the code and its ECU Code 18 which is Throttle Sensor (narrow range). The sensor itself is good. So what can it be? Still need to check the harness continuity, but I came here just in case there's something I don't know or theres a common problem with rx7s of some sort. Any help will be appreciated. Thanks in advance.

HAILERS

In lieu of the continuity check, just warm up the car and backprobe the wire on the ECU that is for the narrow band. The voltage for that pin at idle is in the FSM, Fuel section, CONTROL UNIT pages. On a series five I *think* off hand it's supposed to be 0.8 to 1.0 vdc at idle with a fully hot engine.

EDIT: Pin 2F. Approx 1vdc at idle. And, key to ON, engine off, full throttle approx 5vdc

If it reads approx 1vdc at idle, then for sure it isn't shorted to gnd. You might watch the voltage with the engine off, key ON as you press to full throttle to see if you see anything *funnY*.

Eternal_Gamer

iTrader: (10)

weird, because all I did was get drunk and the car was fixed. not exactly as it sounds but all tests went good. but i still got the CEL. I tried swapping in 2 other TPS spares which one turned out not reading any resistance and the other having 7k+ at full position, and actually idled but ran like ****. So I take out the FCON and put the original TPS back in, and the problem is fixed. Maybe, the FCON harness was bad? I don't know, but the CEL is gone and the engine runs good, but a lot slower now without the mods. Still pulls good though.

schmol

I think I read that someone sprayed some lube down into those sensors and it fixed his/their issue.