Help with a diagnosis!

[law]

I have had my stang for a little over 2 years now. The only mods to date (that I am aware of) are CAI and flowmasters. It is an automatic...one problem I have had a few months after I bought is that after it is warm, once I start it up it would have a really poor idle in park, not really bad but noticeable. But if I were to put it in gear (drive or reverse) then it would act like it wanted to die. Most of the time it never would die on me but it gets very close to it. Once I start to drive it then it is fine, only if I were to turn the ignition off then later start it up again. And it never does it to me when it is cold (like when I start it in the morning). I had my torque converter replaced about a year ago, and I was told that would cause it to do that. But soon after I had that done it still did it, so I ruled that out. Then I was told it was my aftermarket CAI, that I just needed to put the stock one back on, which I do not have, is there any truth to that? The dealership could not find anything else wrong. Anyone have any ideas what else it could be?

 

[Joes95GT]

It is impossible for the CAI to be doing that. What they probably mean is that you have a bad MAF sensor which is caused by the aftermarket CAI - not right. So the car doesn't idle right when it is in park but it drives fine and idles OK when you are driving. My first guess would say it is the plugs and they either aren't gapped right or just plain old, and that is what is causing the miss. I don't think it is a fuel problem because the car drives fine. I had a problem with my car a few years ago, and it ended up being a clogged catalytic converter. It hunted and hunted for an idle, but could never find one, but it drove rough too. It bucked all the time. When is the last time the car has gotten new plugs and wires. I would do them first, then move onto a fuel filter, cap, rotor. Try pulling codes from it.

Joe

 

[law]

Bucked meaning hesitation. I pulled the codes and I got lean condition in the O2 sensors bank #1 & #2, that is all. I changed those about 2 weeks ago. My plugs were replaced about 3 months ago. Besides the poor idling when warm, the only other problem is the hesitation I get when I drive it, but once I start driving it, the idle problem goes away but not the hesitation. What do you think?

 

[Joes95GT]

So the car doesn't drive fine? Hmmm, then that would lead me to believe that it is a fuel problem. What do you mean by hesitation? Like the car doesn't want to go when you floor it or the car doesn't want to go at any kind of speed? I would say it is fuel pump or fuel injector related. How many miles are on the car?

Joe

 

[law]

Yeah hesitation meaning when I floor it, it wont go anywhere. Sometimes it will catch and it will give a burst of aceleration but not usually. It has a little over 63,000 miles on it.

 

[94GTLaserRC]

I bad MAF sensor (or just dirty) can cause innaccurate readings to the computer, making the computer "think" that the car is lean or rich, and compensating by causing the other condition to occur.

Dealers HATE aftermarket $hit
RC

 

[law]

Thanks...I will check to see if it needs to be cleaned. I know it cant hurt.

 

[law]

I think I found the problem. This describes my problem to a tee courtesy of Autozone website: Common idications of Injector Problems: An injector that is stuck partially open causes loss of fuel pressure (most noticeably after the engine is stopped and restarted within a short time period) and flooding due to raw fuel dribbling into the engine. That is exactly what happens to my stang. The more I stop and restart once I put it into drive or reverse it would act like it wanted to die...then once I start driving it the idle is fine but I get a lot of hesitation when I drive...it just does not want to go anywhere when I press on the accelarator. I do not have the means or know how to check the injectors myself so what am I looking at for someone else to do this. Would the injector(s) cause all those symptoms I have described?