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Bad start when its warmed up?!

2K views 12 replies 3 participants last post by  VANY 
#1 ·
hey, guys..i brought this up previously and now still having the same issue. so far, ive checked vac leaks didn't find any, i replaced my fuel pump to an A/M, checked my intake and still having the same issues and also the car shakes a lil bit when im idle. feels like im losing power too and the car surge when im pressing on the gas. Could this be a clog fuel filter, has anyone replaced a fuel filter before? I am sending a link pls. watch the video and see who can come up with a diagnoses.
here's the link..

https://youtu.be/HTPijW0r9ZY

any inputs will be valuable!

thanks in advance!!
 
#4 ·
Cant hurt to try the fuel filter.
Not sure whats involved with swapping them for the 07 but shouldn't be to hard.
I had a vehicle act crazy like that in the past "forget what make" and it turned out to be the MAF sensor.
 
#5 ·
those are the first one of the few that i've checked and still and it still doing the same thing, it improved a lil bit but, I can still feel the rough idle and everytime I restart the car when its warmed up, it chokes like its gonna stall. I was also thinking it could be my O2 sensor?! I haven't changed my sensors since I got the car and I already quite a mileage on it.

By the way, is it better to change both front/rear sensors at the same time or i could do the front and take care of the rear later on?
 
#6 ·
Pretty sure if it was a bad 02 sensor you would have a CEL.

Did you try any fuel inj. cleaner?
When is the last time you changed your spark plugs?
Did you clean you MAF or just give it a look over.?

Its best to try to minus things out before going out and buying parts that aren't giving you any probs. Hate to see ya go out and buy a new 02 sensor only to keep having the same problem.
Have you messed with the 02 sensor at all, they usually won't give you any problems unless you mess with em.
 
#7 ·
I have tried fuel injector cleaners, it'll be good for a lil while and then back to the same issue. Ive changed my plugs not even 6mos ago and I cleaned my MAF too. I haven't touch my O2 sensor at all and I have a high mileage already. Isn't atleast 90k to change the O2 sensors? I just thought that it could be failing soon, that's why I don't have CEL right now?

What about the PCV valve being clogged, would it give me a CEL?
 
#8 ·
I have 154k miles on my 02 sensors and never had any problems with them.
You could try the 02 sensors and if its not that then return them to the store if you wanna try that.
Just make sure you are able to return them because that would suck to spend that kind of money and not fix the problem.
 
#9 ·
Definitely, every penny counts!

also another option that im considering, is to install a wideband O2 sensor to see my AFR, I could be running rich? what do you think, would that be a good option?

I'm looking at AEM, do you know where is the best spot for the bung?
 
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