went from surging to rich/steady 1000RPM

[KayTeeGST]

So my car been surging from 1500 jumping to 2000 RPM'S, CEL on P1400, P0125, P0170 which is coolant sensor and some with bank 1 fuel trim and something else I see people post similar CEL codes w/ same issues. I only replaced MAF so far didn't make difference still surges bad. Any who usually after being in traffic an hour and driving around my car stops surging and idles rough . Gauge chilling at rich . But today after 10 minutes it stopped surging the whole way home, it actually sucked cause I knew something probably happened but ECU was giving system to much fuel so started misfiring, it usually takes less then a quarter tank getting home it took at quarter and some change the smell was so strong was giving me a migraine and my CEL turned off and idle wasn't rough I thought car died when it stopped surging . Idk if it was my 02 sensor that gone out but would like a general idea before looking at it . Like to research before getting into things .

 

[Alex553]

Replace your coolant sensor . That could cause you to run rich

 

[KayTeeGST]

Really . Or is it because the ECU thinks it's running cold ?!

 

[Alex553]

If the coolant is bad (which you have a code for) it will give wrong readings to the ecu which will mess with your afr. So yes the ecu might think it's running cold

 

[KayTeeGST]

Oh okay I didn't have a clue as to the coolant sensor could do that . But makes since thank you very much . But also as for all the codes I need to replace the 02 sensors and the ISC ?! And probably do a tune up ?! If it starts surging again would that help the surge issue .

 

[lasershark]

Do a boost leak test and test your ISC. Read through this link
http://www.dsm.org/how-tos/tttt/tttt3.html
or this one
http://www.vfaq.com/mods/wayback/BradBauer/engine/surge.html

P0125 Excessive Time to Enter Closed Loop Fuel Control
P1400 Manifold Differential Pressure Sensor circuit.
P0170 Fuel Trim Bank 1.

 

[Alex553]

I would replace the coolant first. And erase codes.

 

[KayTeeGST]

Will do so since I am doing my timing belt/water pump/gaskets/seals and tensioner a basically all top end as well so coolant sensor and that's it until I check the other parts .. Okay thank you, Also those links ares super helpful I read one of em but thank you ima save those until I fix my surging haha .

 

[lasershark]

No problemo
for your fault codes... Bookmark this
http://www.troublecodes.net/mitsu/