I have a 98 ranger with a 3.0 v6 and a 5 speed standard transmission. My problem is stuttering and shaking whenever I hit the gas going up a hill. I figured it would be spark plugs and wires, but I replaced them a couple months ago. I also replaced my coil pack last week. The issue only occurs at random times, and acceleration is an issue. My guess is dirty or clogged injectors. Any thoughts or advice? Thanks in advance.
Have you checked the fuel pressure?
Tester
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For performance problems noticed most during rapid acceleration and up-hills on electronic fuel injection vehicles I think first of
- fuel pump or fuel pressure
- fuel filter clogged
- air filter clogged
- obstruction in air intake path
- exhaust system not flowing freely (possible clogged cat)
You’re not hearing any engine pinging, right?
If you can measure the fuel trims when this is happening vs when it isn’t, that might provide a clue.
Is your check engine light on?
No codes as of now. Last week it threw a code for a cylinder 6 misfire, but it went away after replacing coil pack.
Engine runs fine. No knocks or pinging. It idles fine and accelerates fine except for when it acts up.
Haven’t checked yet. Although it seems like it could be a bad pump. It starts right up every time though.
Hey guys, thanks for the speedy replies. Best forum so far. Haven’t narrowed it down yet. I’m treating the injectors with sea foam, and I plan to check my fuel pressure. It only happens in my high gears though (4th and 5th), which confuses me.
One more idea: Check the battery voltage and alternator output. Increasing engine rpm puts more demand on the alternator to power the ignition system, and if the voltage drops the spark becomes weak and results in misfires. If your scan tool has the capability of checking pending codes, there may be more misfire codes pending. If the computer detects a misfire it often won’t output an active diagnostic code right away, but stores it as “pending” while it waits to see if more misfires are detected within a certain amount of miles.
Could also be worn u-joints or a warped clutch.