msc

Hey so I have a lack of power and between 12-1700 rpm it sputters it idles fine but a lack of power it has a cold air and higher flow cats. Now the check engine light pops up after couple hundred miles and then no recirculation exhaust gases
Would the cats cause that or the o2 sensors causing the lack of HP. Should I put the 35 pound fuel injectors in

Matt's 95 Stang

Welcome. Yes - the cats could cause the lack of power, bad MPG and CEL's (check engine light). But a bad O2 sensor could do the same thing. What kinda aftermarket cats do you have? When was the last time you did a tune up on the car?
I have 3.73's, p&p heads and intakes, and 17's on my 95 and I still get atleast 21 MPG so you should be getting alot better then me.

Matthew

msc

Well I changed the plugs wires on a normal reccomended basis oil the same heads have been milled stock headers stock cats with 6 1/4 drilled holes not all the way through the cats but in theory to increase flow have not changed o2s but if no o2 code there. Still good right and I'm on 17 s too I use 91 octane and now its getting worse since first post I think fuel injectors but Idk if I should put the 35 lbs that I have

mustangmike09

lol put those 35#s in there. I dare ya

5mpg will be amazing ! haha


Go get your codes read and let us know what they are, number and what it says.

And if your not tuned to run 91 octane, dont run it.

msc

No recirculation of exhaust gases valve stuck or incouperitive hey atleast the 35s would explain to me why I'm losing power. So should I find a tuner maybe the o2 sensors reading. The wrong info

Matt's 95 Stang

^. English please.

Matthew

msc

I got told fords egress bailed get clogged but fixed the cel but still 17 MPG I'm thinking there's a bad injector And the car needs tuned but as far as 91 octane I live in Colorado high altitude. Less oxygen

gunn

Q: Why would you upgrade the fuel injectors if you haven't solved all of your stumbling problems.

I'm not sure I follow your logic here and the lack of periods in your posts are helping.
* You are seeing bad MPG.
* Your car throws up the occasional CEL every few hundred miles.
* It sounds like you might have solved that issue by cleaning the EGR valve/pipe.
* You still have poorer than expected gas mileage.

Now your plan is to upgrade to larger injectors? If you do so and don't change the ECU to take into account for the larger injectors, each pulse directed by the ECU will spray more fuel than before.

This will cause you to run richer, make less power (engine bogs down), and FURTHER lower your fuel economy.

With a car from 1995, I'm willing to bet that one of the O2 sensors is no longer operating efficiently. The key is to figure out which one. On all my OBD2 cars which have had O2 sensors go bad, they conveniently threw a code to tell me which one I should replace.

Q: Have you checked the codes yourself?

-g

msc

Yeah I always check them myself and it was just the egr problem when I did the test with the engine running the o2 reading seemed fine fluctuated from rich to lean back to rich and so forth by reading the oms I'm thinking because I have not had the car programmed there isn't the right amount of back pressure to heat the 2 oxygen sensors for the Ecuador to know what's going on so my understanding is more air into engine faster flow out its running cooler then it should right which makes it run leaner but in that since the o2 behind the cat reading a different story and it has great power at 6 am but when it gets warm it runs like a fat lady climbing up a mountain.