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Master Tech Lee
Master Tech Lee, ASE Master Tech
Category: Car
Satisfied Customers: 582
Experience:  36 years Domestic and Import Electronics Diagnostic Tech
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I have a 3.1 L V6 with 245K on it. I runs hesitates and misses

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I have a 3.1 L V6 with 245K on it. I runs hesitates and misses severly when cold and improves a to a stumbling miss when warm. I have replaced the fuel filter, repaced plugs, ign. wires, rotor and cap, O2 sensor and have compression of 145-155 in all cylinders. This all sarted after I had a new muffler installed. Althought the rodeo ran fine on the way home. I am at loss, The injectors seem to be working(subjective) and the engine reves prefectly under not load.

Leon Davidian, Sr. :

Welcome to justanswer.com My name is XXXXX XXXXX online automotive technician. I am reading your comments. I will be right with you. Thank You

Leon Davidian, Sr. :

Did the muffler shop weld anything to Rodeo?

Leon Davidian, Sr. :

I should say did the muffler shop weld anything on the exhaust system?

Customer:

yes the new muffler, that is all

Customer:

I did put a new ignitor in also.

Leon Davidian, Sr. :

ok, sometimes the welding will interfere with the computer. Do you know if the positive cable was disconnected before welding?

Customer:

no i do not know that for a fact.

Customer:

I also put in a new battery

Leon Davidian, Sr. :

was the battery dead or not charged?

Customer:

the battery was 12 years old but work fine. started easy.

Leon Davidian, Sr. :

ok, Is the check engine light on and/or has it flashed then gone off?

Leon Davidian, Sr. :

If so I need the codes hard fault and memory

Customer:

it comes on after running for awhile and goes off. but it has done that for 150K. nothing new.

Leon Davidian, Sr. :

ok is there a way for you to pull the codes for me

Customer:

i don't have a code reader.

Leon Davidian, Sr. :

like AutoZone will for free - but the light has to be on

Customer:

that will have to be another day. I won't have time to work on it for a week.

Leon Davidian, Sr. :

this is important to me to see what is going on- i understand the light has been doing this for sometime, but it will help me help you with the hesitation and miss. Too, there maybe a new code for this new problem.

Customer:

do you have any educated guesses? I did look for vacuum leaks and found none.

Customer:

well I guess that I am stuck until I get a reader.

Leon Davidian, Sr. :

OK, what we can do is set a time or let me know when you can do this and i will be there. what we need to do is for you to rate this chat and we will be connected until you are satisfied with the repair.

Leon Davidian, Sr. :

As long as it takes no more money from you just your time and my direction

Customer:

ok

Leon Davidian, Sr. :

I hope the computer is not fried from the welder - this has happen on rare occasions

Customer:

I hope not. to.

Leon Davidian, Sr. :

now this chat will go into a regular chat not live from there you can post to me anytime you need

Customer:

OK thanks for your help.

Leon Davidian, Sr. :

i am going to siwtch us now if that is ok with you

Customer:

yes thanks, XXXXX XXXXX not cosider the computer.

Leon Davidian, Sr. :

Is there an autoZone near you?

Customer:

yes and O'rileys and auto zone.

Customer:

I will do that next weekend when I have time.

Customer:

Thanks again.

Leon Davidian, Sr. :

OK just let them know you have a light on and goes off and you would like to know the codes and they will let you know the codes.

Leon Davidian, Sr. :

ok

Customer:

I will thanks for your help.

Leon Davidian, Sr. :

here we go make sure you rate me now and the system will switch , Thank you, Leon

Master Tech Lee and 5 other Car Specialists are ready to help you
Ok here is where you and i can chat, Let me know what you find - take your time.

Leon
Customer: replied 3 years ago.


Turned out to be a bad replacement plug. I found one with a crack in the insulator. The original problem was a bad plug wire which I found by looking at the plugs. Everything works fine now. Thanks again for your help.

I am glad you found the problem.
Thank you for using justanswer.com,

Leon
Master Tech Lee and 5 other Car Specialists are ready to help you