2.9 Hesitation/stumbling

[kmans88]

Hi all. Have an 88 Ranger 2.9, 5 speed with 355,000 miles on it. This has been occurring for a bit. On acceleration from a stop the engine wants to hesitate, stumble. Fluttering the pedal gets it past this point and while your accelerating it's ok. Same thing occurs when your driving along and want to accelerate but not as bad. I don't flutter the pedal at this point just hold it down until it clears. Drives down the road fine. Any ideas. No codes. New O2 sensor, IAC, and intake air temp sensors installed recently(failed emissions). Timing was ok.

 

[Big Jim M]

Have we checked plugs, wires and coil? In a carbed engine you describe a lean condition under accelaration.. However in a fuelie it could easily be lectric.
Big Jim

 

[kmans88]

Fuel injected. Yep, plugs, wires, cap, rotor all good. Less than 30k on those. Installed with new heads. Coil was changed once a number of years ago. I've had the truck since new. Son drives it now.

 

[holyford86]

check the fuel pressure

 

[Big Jim M]

Put nuther coil on there and see what happens.. coils wear out bout as fast as plugs.
Big Jim

 

[holyford86]

Put nuther coil on there and see what happens.. coils wear out bout as fast as plugs.
Big Jim

Coils do not wear out in 30k miles, like most plugs. My coil lasted over 220k, Replacing a good working coil is like putting on a condom after getting laid, it just doesn't make sense.

 

[IMenriched]

Check the in tank pump to see if it is working? if applicable

 

[kmans88]

FYI- Coil wasn't replaced 30K ago. It was replaced a number of years ago. Don't remember when specifically, somewhere between 5 and 8 years I'd say. Would the fuel pressure regulator cause this? I replaced it once at around 200k. Did a smell check of the powerbrake vacuum hose. Gas odor was very evident. Not so this time.

 

[289-tiger-]

Congratulations on the mileage. If injected try cleaning the throttle body with CRC intake cleaner at the butterfly.

Good luck

 

[Big Jim M]

Holyford .. We agree... Many coils last the life of the engine. However, when a vehicle runs long enough to heat up the coil and then stops running a good bet is the coil. When cold they will still do their job (sometimes) and as they heat up they stop working.
Big JIm

 

[Chris102371]

With the truck running,grab the throttle position sensor and try to wiggle it side to side and see if the engine stumbles or does anything weird.

 

[Project Ranger 87]

my friends did tht and it was fuel pressure, the in tank pump was good it was the other one that was bad...