For starters a few months ago i bought my 94 ext cab 4x4 with a 302 and a 5spd. And from being in wisconsin its whole life it wasnt to rusty, but when i asked the guy how long the check engine light was on, he said since a few years ago, me and my step dad timmed it and replaced the clutcha and two u joints, and after driving it daily i pulled the codes cuz im only getting 10-11 mpg. I replaced the vaccume solinoid on for the egr, than investigated the egr and found that the diaphram was ripped so i replaced that. I still got the codes, so than i ran a vaccume line from a free port off the intake manifold to the top of the egr, and had to squeeze the line with a hose clamp b/c there was too much vaccume. So when i drove to school the next day the check engine light was off and it was up to operation temp, but it started to die out on me and wouldnt start so i un did what i did, and have the check engine light again, what do i do now??

 

Dup.

 

Your little mod will guarantee a 172. No other codes? hard to believe! How old is your o2 sensor? EVP senor is more likely bad. Is everything put back the way it's supposed to be?

 

Ya its all backthe way its sposed to be, i get 172 and the 327 code. the o2 sensor maybe stock, but when i bypassed the vaccume soilnoid if it was bad wouldnt it have thrown the check engine light?

 

Was the 172 & 327 KOEO, continuous memory, or KOER error codes?
Running them (o2's) over 60 K mi. will cost you MPG's. Even if it is somewhat functional. The switching speed slows & they also become inaccurate. I toss mine at 30K. 1 reason I double your MPG. Once again, replace EVP sensor & o2. Then disconnect the battery for 5 min., take 2 aspirins & post the results! If aspirin upsets your stomach, drink a beer!

 

since im only a jr in h.s. and have a limited income,
im guna replace the evp sensor first, i tested it and with the plunger all the way up, and it did do nothing, it was at operating temp. than down the road if it solves it ill replace the o2

 

You mean if it doesn't solve it? Especially if yours is stock, a new o2 will pay for itself in gas savings. That is what dictates air/fuel trim!

 

hopefully it does, and i wouldnt doubt that the 02 is stock. Hopefully the evp sensor and o2 fix u mentioned will get me back up near the adverage mpg other pp with 302s get.

 

i do realize the importance of the o2 sensor and what it does, like you just said along with my advanced autos teacher it controls it and over time they wear out

 

It will help. I hesitate to urge people to spend money on parts potentially unwarranted. I really don't think this is the case here. We are a little hampered by having only your descriptions to work with! Sometime getting the info we need is harder than pulling teeth. Although this went pretty well. After you get it running healthy w/o active error codes, we can concentrate on making some real performance gains simultaneously w/ noticeable MPG improvement relatively inexpensively (less than $200.). Start saving!