05-26-2008, 06:44 PM
Hey guys well i have a base tune for my turbo focus and it drive pretty good but when i let it idle it goes down to 800rpm (Where i set it) and then it will drop low to 500rpm catch its self and go back to 800rpm and then it does it all over again. Ok im wondering if it could be the alternater i know when the rpm drop the lights dim. also i have a code P1121 Which is a bad TPS or a bad MAF. i have changed the TPS and it helped a little but tyhe light still ame back on but i really doubt i have a bad MAF. and finally when i drive the car sometimes the car starts missing i let off the gas and then back on the gas and its fine. could this all be the base tune, Bad MAF, or bad alternater, Or something else please help me
05-26-2008, 07:51 PM
have you checked your idle control valve?
same thing happened to me long time ago, but it was too long ago....i dont even remember how i got past it.
05-26-2008, 08:39 PM
i have a spare ICV so ill try that thanks but if anyone else has anything please help
05-27-2008, 07:20 AM
I would check all the things on the scan tool and see what itsnt showing correct readings before I went and just started changing parts
It could be as easy as a bad o2
05-27-2008, 01:47 PM
Hey Tom what do you mean a scan tool like the one at autozone or my xcal2
05-27-2008, 02:50 PM
Jim your killing me..... Xcal2
05-27-2008, 03:02 PM
hahaha sorry John i checked it with the xcal and all that comes up is P1121 Which i looked on here at the DTC codes and this is what it say
Throttle Position (TP) Sensor Inconsistent with MAF Sensor The PCM monitors a vehicle operation rationality check by comparing sensed throttle position to mass air flow readings. If during key ON engine running self-test the comparison of the TP sensor and MAF sensor readings are not consistent with calibrated load values, the test fails and a diagnostic trouble code is stored in continuous memory. Air leak between MAF sensor and throttle body
TP sensor not seated properly
Damaged TP sensor
Damaged MAF sensor
Drive vehicle and exercise throttle and TP sensor in all gears. A TP PID (TP V PID) less than 4.82 % (0.24 volt) with a LOAD PID greater than 55% or a TP V PID greater than 49.05% (2.44 volts) with a LOAD PID less than 30% indicates a hard fault.
so what do i do
05-27-2008, 03:03 PM
o John by the way im finally getting tom to tune my Focus THE RIGHT WAY :)
I just got to set a date to fly him out to FL
05-27-2008, 05:54 PM
You need to check the voltage of the TPS with the xcal as well as the MAF reading at idle and reving it slightly
Your xcal2 does far more then just read codes it also will tell you if each part (TPS , MAF , O2 Etc) is working correctly and what reading it is giving the ECU
05-27-2008, 09:46 PM
hey guys also forgot to mention when i start it up in the moring it sounds like its on 3 cylinders for like 2 seconds then it jus roars and its fine
05-29-2008, 05:11 PM
try checking all of your bolts and seals, check your spark plug gap too(maybe wires too). sometimes if the spark plug gets too hot, it will gap itself out a little bit over time, as uncommon as it is, it is worth a shot. when is the last time you had those bad boys out? i ususally check mine in my SRT about every other oil change or so.
05-29-2008, 09:42 PM
Hey guys ok well i bought a new MAF and a new TPS and it idles ok most of the time but sometimes it does the same thing and i will get the same P1121 code but what is it. in cold start it still starts on 3 cylinders for 2 seconds then its perfectly fine and runs strong the AFR is fine im totally stumped.
05-30-2008, 08:13 AM
Stop throwing parts at it , I didnt think any of those were bad to start with that is why I said to check them FIRST , My guess it is in the tune , need to get a good tune
05-30-2008, 09:09 AM
ok Sorry Tom for not listening this is Jim i talked to you on the phone about a week and a half ago. this is still the base tune that fernando gave me but he modifieed it a little bit on the dyno. Tom fernando sent me the the unmodified base tune over email do you want me too send you it to you.