2008 CX-7 Turbo Misfire

[Monty&Mia]

Hi new here, learning the forum,
I bought car for one of my kids who just got license. They liked driving my wife's 2010 mazda3.
So bought the 2008 cx7 bought about 2 months ago has a 116,000 , it started week after I got it misfire #3, (coil was bad) , pulled it apart did coils, plugs(iridium),had a small leak radiator, replaced that, water pump, thermostat unit,& serpentine belt. Then found that the battery terminals loose tightened and replaced positive cable end, battery is less then 6 months old.
Finally code went away for almost 400 miles then went to pass some on thruway ding goes the light for misfire coil 2.
I put injector cleaner in but happened again
So should just assume bad injector
Or what else, would anyone know of reasonable priced place to buy it or them.
And should I replace all 4
I tried few bone yards hard to find parts
Thank you in advance,
James

 

[edmaz]

.... So should just assume bad injector ..

Why?

 

[Monty&Mia]

I was figuring that is what most articles I read are focusing on I have a foxwell code reader I have been learning to us. I have been checking live data .
TODAY on way home from work had to get up to 65 fast and it threw multiple. Misfire for the first time started hesitating

 

[edmaz]

I was figuring that is what most articles I read are focusing on I have a foxwell code reader I have been learning to us. I have been checking live data .
TODAY on way home from work had to get up to 65 fast and it threw multiple. Misfire for the first time started hesitating

Well, trying to diagnose with that tool is definitely much better than just throwing parts at the problem, based on what you read online.

What is the range of fuel trim values that you're seeing from the reader with the engine warmed-up? Also, what about MAP value at idle, and also at 2K steady RPM, also with a warm engine?

 

[Monty&Mia]

I will check those this evening when I get home I took my car to work told my daughter not drive it today.
She wasn't happy she had to take the 05 grand van with 235,000 on told her be nice to the old girl lol
Thank you for helping
James

 

[Monty&Mia]

I tried this hoping I wouldn't mess up answers

 

[Monty&Mia]

Short term fuel trim at idle was 0%

 

[Monty&Mia]

Ok at 2000 rpms

 

[Monty&Mia]

Short term fuel was at 2000 rpm1.58 % to 0.78%
These all were taken after driving for 45 minutes
Thank you in advance you can help me with
This is my second mazda in my family , mostly, dodge and chevy
I got a deal on this for my daughter as her first car
And 4 years ago my friend sold me his 2010 mazda 3 I with 78,000 on for under
3,000 he didn't like what he was getting for trade in went to leasing
Thank you again

 

[edmaz]

The numbers on the reader look ok to me, and don't suggest anything being wrong with the injectors IMO. I'm wondering if perhaps that rad leak resulted in an engine overheat for the previous owner, and recommend you do a compression test before replacing any other parts.

 

[Monty&Mia]

Ok thank you I will try Monday while I am off
I was thinking same thing on the numbers when I searched each one up
Thank you again, I am going nuts and like you said don't want to just through parts at it. But, one good thing I have a compression test kit I got from harbor freight, but a friend borrowed it, good chance to ask for it back.
I will do some more searching get the compression range for it.
Thank you again,
James

 

[Monty&Mia]

Ok if I read correct the compression should be 150 to 180 , I read so many last night my eyes sore .
I am going to try to get to it Mon , my wife's 2010 mazda 3 eng light came on last night and of course do for inspection this month .

 

[Monty&Mia]

Morning I didn't want to be rude I haven't got my compression tester back yet
Should have this weekend
I can't wait to check now it, because now it's just no.3 not 2 started this Monday night
Thank you
James

 

[Monty&Mia]

I am sorry been so busy kids ,work summer, I had different problem come up wouldn't start jumped started and found out battery cables were loose tightened them up, no misfire in about a 4 days now(of course friend hasn't returned my compression tester hasn't been retuned)
Thank you

 

[Monty&Mia]

The numbers on the reader look ok to me, and don't suggest anything being wrong with the injectors IMO. I'm wondering if perhaps that rad leak resulted in an engine overheat for the previous owner, and recommend you do a compression test before replacing any other parts.

Hi I wanted to thank you for the help with my daughter car I took everything you had said

Then just recently a deer hit my daughter's car it was totaled bought but it back while collision shop had apart I changed timing chain and found out that the timing had jumped 1 tooth , I am hoping this solves the mysterious misfire that happens maybe once every once in a while.

I just wanted to thank you because when I took car apart the first thing I remember was your answers helping meI