Surge Update #2

[rruddfan21]

hello all!! for those interested, i did some work to my metro this weekend. i tested the TPS, and it checked out fine at all throttle postions. i also noted that the radiator fan turned on, so ECT sensor is okay. I made sure the IAT was getting voltage, and also checked resistance. again, checked out ok. only thing i noticed was that my PCV valve is nearly clogged, and i changed it around may/june. this means it got clogged up quickly. what would cause a PCV valve to clog up so quickly? i think this may be the problem but first i need to out what would clog a PCV valve so quickly. thoughts??

[mcalvo]

Carbon?.. maybe too rich air/gas mixture that creates excesive carbon? What is your MPG?

Could be, isn't it?

MC

[mik13usa]

PCV is usually drawing from the valve cover (cam cover) so somehow it is pulling oil into it and getting clogged I always use the AC Delco PCV NOT the Fram, for some reason the fram has never worked right on my 94, do you have oil in the air cleaner base? this is usually from a failed PCV

[rruddfan21]

MC- what would cause i rich mixture? engine ignition is tuned up fully. replaced air filter in february and it is a little dirty, and PCV was replaced in early May. i shook it and only rarely i heard a very very faint rattle, telling me it is pretty clogged. very little oil in air cleaner assembly. i plan on replacing air filter and PCV just to see what this does (even though they shouldn't need replaced already!!!). maybe my O2 sensor is weak? no cehck engine light but dunno how old sensor is and it is only last sensor that may be causing surging. MPG---around 30 (i calculated 33 at one time). remember.....it surges when i let off throttle and pick it back up; and it shifts a bit later out of second. idle isn't rough but not real consistent. also sounds like very faint, random popping noise by alternator/belt area. thoughts??? we are gonna solve this surging metro!!!

[rruddfan21]

i'm going to replace the O2 sensor....that is what i think it may be. faulty O2 causes"searching" idle, rich mixture (plugged pcv) and surging. all of those apply to my metro. we'll see if this fixes it this weekend