My 99 with 160,000 finally has a problem(other than heater core 2x) Idles slightly rough not to bad, in park engine sounds runs good. when driving sounds very sputtery for lack of a better term. loss of power as well.

new spark plugs, check
new cables, check
new o2 sensors, check 3x
new air filter, check
engine block test, blue
obdII no codes
obdII code relaying check, by disconnecting air flow sensor, Check

I am leaning towards exhaust issues, I do run K&N with flowmaster exhaust nearing 8 years of age, original cat,

only replacements have been maintenance other than heater core
shocks, brakes, tires, alternator, battery, oil, lubes, coolant.


muffler shop?

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99 ford ranger, 3.0 automatic 4x4 no real upgrades makes it everywhere like it is.

Fuel filter/pump?

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Chaz

86 Chevy Silverado
soon to have 92 Ford ranger

just did the fuel filter last year 4,000 miles. engine sounds perfect in engine bay, sputtery noise from exhaust back noise can actually kinda be felt in pedal. no typical rattles or odors i have previously experienced with my chevy cats

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99 ford ranger, 3.0 automatic 4x4 no real upgrades makes it everywhere like it is.

hmmm weird cat clogged

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Chaz

86 Chevy Silverado
soon to have 92 Ford ranger

Clean the IAC

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2003 Ranger Edge ... crashed

2011 sport 4x4 with a little modification

Could be fuel injectors, they usually die of natural causes before 160K.

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Torch Red 2004 Ranger Edge 4x4, 4.0 SOHC w/5speed manual, R7-8.8 LS 4.10 diff

Thank you for the responses and advice, I will try this today. I was looking at the iac yesterday now at least I know what it is. I am also going to try the seafoam for fuel injectors.

Like many ranger owners on here I am very attached to this truck, it has taken me so many places and always brought me home. I lived above a seven mile stretch of beach for awhile and I can not count the number of trucks, and suvs it has pulled out, among the most memorable where the yukon burried to its frame, a brand new kia with 150 miles on it burried to bumpers(owner cracked its transfer case before our attempt) and the park rangers full size dodge to dug to its axle.

.

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99 ford ranger, 3.0 automatic 4x4 no real upgrades makes it everywhere like it is.

misfire on #2 CYLINDER, no spark = bad coil. replaced with motorcraft coil problem solved. I am still going to clean the iac and other sensors while i am at this and probably do a seafoam for hits and giggles.

talked to a mechanic friend of mine about why it was not throwing misfire codes, response was; ford obd takes a bit of driving time before recording any types of codes. ?? fortunately I parked it and drove the e350 super duty until i had time to deal with it. my guess would be that pushing that much raw fuel through the cat would most likely foul it. Wonder what unburnt seafoam would do?

Thank you for the replies and help. I will update any performance increases with seafoam and iac cleaning.

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99 ford ranger, 3.0 automatic 4x4 no real upgrades makes it everywhere like it is.

cleaned engine bay today along with cleaning and coating K&N I have had sitting out for the last year, did 3 step seafoam treatment, cleaned IAC, and MAF.

Needless to say, but I will- along with the new plugs, new cables, new coil, and all three new o2 sensors the ranger runs like new. It is hard to believe it has 168,000 miles on it.

Im stoked it is back up and running!

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99 ford ranger, 3.0 automatic 4x4 no real upgrades makes it everywhere like it is.