'97 2.3L Shudder

[runningslow]

My truck is a '97 2.3L 5spd Supercab 2WD, with about 212K miles. I plan to swap a 302 in the future, but for now I need a little insight to keep her on the road.

She usually idles fine, but it doesn't matter if I'm accelerating, in stop-n-go traffic, or cruising down the highway at 70... the truck will shudder or jerk for lack of a better term. She's never died on me.

Also, the speedometer has issues where it'll drop speed, then go back to the real speed when I left off the gas. The odometer quits rolling when the speedo acts up, too. I've test the VSS and the resistance checked out. I tapped into the VSS feed line for the explorer overhead console, but I don't think that's causing all this.

Some days are better than others and I usually don't have a problem during my morning commute when the temperatures are lower, but the afternoon commute home is when she usually acts up.

I've recently changed the plugs and wires. She also seems to use (or leak) a little coolant from time to time.

At least for the shuddering, I'm beginning to think that it may be a spark, or fuel issue, but I'm not really sure where to start looking.

 

[runningslow]

Oh, let me add: check engine light throwing a code for camshaft position sensor and evap canister failure. I suppose I could also be having a timing problem.

I also have the ABS/Brake Light on, had that code read it was a problem with the sensor on the rear axle. I just haven't spent the $20 for a new one, yet.

 

[kimcrwbr1]

check and clean all your grounds sand them metal to metal especially all the computer and ignition grounds. bat to chassis, bat to engine, engine to chassis, and all the little ones throughout the harness. Also look for any shorted wires burnt or frayed especially the O-2 sensor wires. Check for codes to point you in the right direction. Any part store can pull the codes for you.

 

[kimcrwbr1]

Inspect and clean the connectors also get the wiring in order then erase the computer by disconnecting the battery for 1/2 hour then run it at medium speeds till it is hot and then pull the codes. Fix the codes in the order received until you get a pass code and reset the computer after you correct a problem one at a time that is why they are in order one sensor can throw multiple codes always fix the lowest number first.

 

[kimcrwbr1]

Get a tube of dielectric grease and check all the connectors for corrosion give them a squirt and make sure all the pins are pushed all the way in.

 

[runningslow]

Thanks for the input!

Mentioning the O2 sensor, I think I should mention another item: I have several exhaust leaks and no cataylitic converter (shh... don't tell anyone). We don't have emission testing or any other kind of inspections around here, so I haven't thought much of it. I bought the truck without it (granted I didn't know until after the fact).

I'm planning to completely redo the exhaust soon, maybe after the engine swap. The swap (if my wife will let me) should be sometime in the fall.

 

[jhammel85]

Just a thought but all the exhaust leaks could be throwing off the O2 sensor.

 

[runningslow]

I know this is my old thread, but I wanted to post an update for anyone else that may find this thread looking for help.

I was living with the shuddering problem for months and finally got fed up with it. The spedo wasn't working and the shuddering, bucking became unbearable. I first started by getting the exhaust bandaged up. No help, but the truck was a *little* quieter (still no cat). I then replaced the coil packs and the problem was less noticeable and I thought for the most part that I had found my solution. I however still had the P0340 engine code. The truck ran well at most speeds, but at lower rpms I would get some hesitation. I lived with that for a day or two, then the truck started acting like its old self. That was it. I finally decided to tackle the camshaft position sensor, which (on a 97 2.3L) is hiding beneath the A/C compressor and power steering pump bracket......

After a long evening digging into parts of my engine compartment that hadn't seen daylight in over a decade, I replaced the sensor and now the truck is running better than I've ever seen. A great feeling.

Also, while I was diggin around, I tried to clean up the wiring, sanding grounds and whatnot... I also cut the wire that I had tapped into the VSS for the Explorer overhead console. After all that, something I did fixed my speedometer! I'm venturing a guess it was the VSS tap.

 

[runningslow]

Truck is still running great! Not having that check engine light on is a great feeling.

However, the speedo problem is back, but the symptoms are different. The needle does seem to dip a little when I hit the gas, but what gets me is that the needle drops when I hit the brakes. I know, I know... the needle is supposed to go down when I hit the brakes, but I mean its drops to zero when I'm still rolling. It also seems to depend on how hard I hit the brakes. The more I press, the more it drops.

I guess I'll go and look the wiring over again. I still have to track down the problem with my RABS (Yellow RABS and Red Brake light on, with a trouble code 4). Problems might be related? Do the VSS and RABS share any common wiring?