Replaced DPFE, but it's still hitching!!!

[feellnfroggy]

Originally Posted by dogboy

My truck is doign this eaxct same thign for the past 3 or 4 months ( quite annoying). But mine does it at any speed if I get the throttle in just the wrong spot (a somewhat large spot...).

I've been told to check for intake manifold/ vacuum leak, dirt injectors, and the Throttle Position Sensor, fuel filter, and plugs/ wires. I've changed the fuel filter, and plugs, and the wires tested within spec (7k ohms resistance per foot if I recall) with no change.

I ran a can of Seafoam through a full tank, with no changes at all either. I am probably going to hook a vacuum gauge up to it tomorrow and see what it says (7-8 months ago, it read 18-19psi vacuum, or what ever you want to call it).

After that I am going to check/ adjust the throttle position sensor. I've been told you can adjust it, so I'm just going to figure out how to do that and see what it does.

It could be the TPS going bad. But when it does you will know it. There is no adjusting the TPS. It spins 180degrees based on the position of the intake butterfly. The DIS box can be a problem, In my truck it was the coil for the waste spark (2.3l) I have points 1 and 4 were bad and had to replace it. I still have problems. Check to see if the CPS is dirty. Buy a haynes manual to help with disassemblies and assemblies.

[snake]

Originally Posted by RentonRanger

Sorry for my ignorance, but what's 44K?


Will do.

Its some bad-ass injector cleaner- about $23 or more a can and only sold at stealerships and a few oil change places. Local mechanic turned me on to it, works like a mo-fo. Its supposed to be pure techron.

[RentonRanger]

Well, it seems to have worked itself out. It's running just fine now, no bucking or hitching at all! I'm thinking that maybe the PCM needed to "re-learn" the new DPFE readings and it just took a few days of driving to get it right.

I'll keep you posted if something changes...

[feellnfroggy]

Originally Posted by feellnfroggy

It could be the TPS going bad. But when it does you will know it. There is no adjusting the TPS. It spins 180degrees based on the position of the intake butterfly. The DIS box can be a problem, In my truck it was the coil for the waste spark (2.3l) I have points 1 and 4 were bad and had to replace it. I still have problems. Check to see if the CPS is dirty. Buy a haynes manual to help with disassemblies and assemblies.

So I posted all this stuff. Then I remembered........My 96 probe did this, I remember when I was driving my 92 ranger this weekend, and I knew the problem felt familiar. Then it hit me. MASS AIRFLOW SENSOR. I unplugged mine and the ranger is running better. Not perfect but at least its smoothed out some. Same with my probe. (runnin real rich though.) Go to a junkyard and try to find one or three for cheap, swap them out see if it helps.