timingchain
New Member
- Joined
- September 20, 2009
- Messages
- 1
- Reaction score
- 0
- City, State
- San Francisco, CA
- Year, Model & Trim Level
- '97 Ranger 2.3L
But it's not so simple:
When stepping on the gas pedal, even without being in gear (manual trans) there is a delay/hesitation/stumble/hiccup that occurs in the engine. Once moving, the truck idles fine, drives fine, no misses or problems, although being a 2.3 liter, it is a little underpowered.
I have already:
I tested the MAF on my digital voltmeter, which is when I realized the hesitation was occuring without being under load. There was a little jumping around of the voltages when the engine stumbled as I hit the throttle (kind of hard to tell with a digital meter, obviously) and I couldn't tell if the MAF was responding to or causing the hesitation, so I replaced the MAF--$100. It now drives exactly the same.
I tested the TPS, again with the digital voltmeter, it runs up in voltage very smoothly, no noticeable glitches at all--I did this with the engine off, if that makes a difference.
Now what? I would suspect fuel injectors, but it runs evenly under a load, like when accelerating up to highway speeds and all that, and that is where I would have expected a fuel delivery problem to show up.
Any ideas?
When stepping on the gas pedal, even without being in gear (manual trans) there is a delay/hesitation/stumble/hiccup that occurs in the engine. Once moving, the truck idles fine, drives fine, no misses or problems, although being a 2.3 liter, it is a little underpowered.
I have already:
- replaced spark plugs, inspected wires.
- replaced air/fuel/oil filters
- replaced PCV valve
- cleaned IAC, throttle body and MAF
- checked for vacuum leaks
I tested the MAF on my digital voltmeter, which is when I realized the hesitation was occuring without being under load. There was a little jumping around of the voltages when the engine stumbled as I hit the throttle (kind of hard to tell with a digital meter, obviously) and I couldn't tell if the MAF was responding to or causing the hesitation, so I replaced the MAF--$100. It now drives exactly the same.
I tested the TPS, again with the digital voltmeter, it runs up in voltage very smoothly, no noticeable glitches at all--I did this with the engine off, if that makes a difference.
Now what? I would suspect fuel injectors, but it runs evenly under a load, like when accelerating up to highway speeds and all that, and that is where I would have expected a fuel delivery problem to show up.
Any ideas?
