Stuttering Ranger?

[zixxer]

I have a 1998 Ford Ranger 2.5l lima with 110k miles on it ? oil changed regularly, plugs/wires changes 30k ago.

It has had a slight stutter for about 15k miles or so ? it?s most noticeable when going at a steady speed while going up a hill.. It feels somewhat like a slightly clogged fuel filter, except I changed the fuel filter and it?s still happening. My next step is to change the plugs/wires but I think they should?ve lasted longer than this.. Any other thoughts? It hasn?t thrown a code, and since it?s OBDII I assume it would if there was a problem with the 02 sensor or egr valve or something. When the engine isn't stressed (i.e. on a flat highway) it runs fine. This only happens if I push on the gas, and doesn't change whether I push on it a little or to the floor - it just stutters a little bit.

Another symptom (or cause?) is that it runs very poorly on cheap gas. If I run 87 it knocks but it?s ok on 89. I run a bottle of chevron techron fuel cleaner about every 3k miles or so.



Thoughts?

 

[Zenmervolt]

Dirty MAF sensor? It sounds like it's running a touch lean.

ZV

 

[Vette73]

Originally posted by: Zenmervolt
Dirty MAF sensor? It sounds like it's running a touch lean.

ZV

Damm it, beat me again. Was about to say the same.

I recently bought a 1994 Mazda B4000 (i.e. 4.0L Ranger). Got it pretty cheap between gas prices and had a major studder on take off. Person replaced plugs, filters, etc... and then sold it after giving up. I took a q-tip and some cleaner and wiped off the dirt off the MAF element and runs great for 160k+ truck.

 

[Pacfanweb]

Plug wires is the first thing that comes to mind.

 

[zixxer]

Okay - I removed the MAF and cleaned the wires/assembly with MAF-specific spray cleaner. I used about half a can.. But I didn't physically touch the wires with anything since the can specifically said not to.

I let it all dry (I also cleaned the intake) and reassembled everything. It ran even worse than before when I first started it, but over 10 or so miles it has cleared up a lot. I'm wondering if a bit of water got into the ridges inside the plastic intake duct and took awhile to evaporate. However, it still has a slight miss.. It's less noticeable at higher rpm but still stutters..

If it doesn't get better by the weekend I'm going to figure out the voltage the MAF is supposed to put out and test it.. fail that and I'm taking it to a shop I guess. I don't have time to dick around with this stuff anymore.. Arg.

 

[zixxer]

Also, fwiw - zen mentioned the MAF causing it to run lean.. When I would shift it seems like the RPM's would 'hang' a bit before dropping.. Symptom of a slightly lean mixture?

 

[Pacfanweb]

No, that is a normal condition. All cars do that. It's an emissions thing. Unless it's REALLY hanging for a long time.

Have you done the plug wires yet?

 

[Jawo]

damn....I was going to say Fuel Pump since that what my problem was recently. It definately sounds like the engine is running way lean though.

 

[zixxer]

Originally posted by: Pacfanweb
No, that is a normal condition. All cars do that. It's an emissions thing. Unless it's REALLY hanging for a long time.

Have you done the plug wires yet?

No - the newer lima motors have horrible access to half of the spark plugs - changing the plugs/wires is a 3-4 hour job for a home mechanic like myself. I'm going to change those as a last resort since I put NGK platinum plugs and decent wires on only 30k or so ago.. Seems odd for a modern fuel injected vehicle to foul or burn up plugs in 30k.

 

[BeauJangles]

Originally posted by: Zenmervolt
Dirty MAF sensor? It sounds like it's running a touch lean.

ZV

Originally posted by: Marlin1975
Damm it, beat me again. Was about to say the same.

I recently bought a 1994 Mazda B4000 (i.e. 4.0L Ranger). Got it pretty cheap between gas prices and had a major studder on take off. Person replaced plugs, filters, etc... and then sold it after giving up. I took a q-tip and some cleaner and wiped off the dirt off the MAF element and runs great for 160k+ truck.

damn, you two are like our own version of Cartalk :thumbsup: