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Ask Mike V. Your Own Question
Mike V.
Mike V., Auto Service Technician
Category: Ford
Satisfied Customers: 25687
Experience:  25 years experience on all makes and models, Licensed NYS Inspector.
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Idles irradically... sometimes just dies... runs great and

Customer Question

idles irradically... sometimes just dies... runs great and then all of a sudden starts chugging... then runs perfect for a bit... then chugs???
JA: How many miles are on the car? What size is the engine?
Customer: 136k 5.0 ltr
JA: What is the model/year of your Ford?
Customer: 1992 f150 lariat
JA: Are you fixing your F150 yourself? What have you tried so far?
Customer: don't know where to start
JA: Anything else you want the mechanic to know before I connect you?
Customer: no
Submitted: 1 month ago.
Category: Ford
Expert:  Mike V. replied 1 month ago.

Thank you for your question!
My name is ***** ***** give me a moment to review your question and type my reply. Thanks

Expert:  Mike V. replied 1 month ago.

Is this only happening at idle or even when you are driving?

Customer: replied 1 month ago.
when im driving
Expert:  Mike V. replied 1 month ago.


I would try unplugging the mass air flow sensor and then start it and take it for a drive. If it runs better, then replace the sensor. If not, then you may have an egr valve sticking open or an issue with the catalytic converter plugging up. If the substrate is loose or broken up in there, it might be blocking off the exhaust causing some back pressure which would result in the engine running poorly. These are the areas I would start with.

Please let me know if there is anything else I can do to help.
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Thank you so much!