I noticed recently that my throttle wasnt right and had some misfires. Also was starting very poorly. When I looked over the engine I noticed my TPS connector has slipped off (cause the clip is broken). So i thought voila, and plugged it back in. I even reset my codes before starting back up (codes were: Engine speed (RPM) sensor -circuit, Ignition reference signal -no signal, Throttle position (TP) sensor -circuit). When i did i started nice but when i am throttling past idle, I can hear electrical arcing from around the distributor. its loud enough to hear from inside the cab, and as you would probably guess, causing the engine to misfire even worse than before.

As I understand it the computer puts the engine into a sort of safety mode with predetermined air fuel mixture when there is a problem, and notice this happen when i unplug the TPS while the engine is running. The idle lowers and noticible less power driving that way.

What would cause this? A bad ground? I inspected the lead ignition wire and the 3 (2, 4, 6 ) ignition cords to the plugs, cleaned them up and noticed only a bit of arc burn on the lead. I put a few layers of electrical tape on it but the same arcing noise is occuring upon throttle. TBH the noise sounds like its underneath the distributor.

Any input appreciated, Thanks.

 

BTW its a 3vze. The strange thing is that does the arcing stutter behavior much worse with the TPS connected

 

I'm not sure your TPS being unplugged has anything to do with ignition arcing. You don't mention the age of your ignition parts, but older worn parts are the usual suspects for ignition arcing. Arc burn evidence on the coil to distributor lead you mention would tend to support this. Suggest replacing the following:
- New spark plugs, gapped correctly (0.031" or 0.8mm) & make sure the plug threads in the head are clean. The plugs ground thru the head, as does the distributor.
- New wire set
- New Distributor cap & rotor

Also do yourself a favor & guy some quality parts for this, it pays off in the long run.

 

The difference between running with the TPS and without it is obvious. I cant even get down the street before bogging out even on a steady throttle, when the TPS is connected. I can drive all over town, although sluggish, with the TPS disconnected. Also the arcing noise is much more prominent and really only noticable when the TPS is connected. The lead ignition wire that showed signs of arcing is the newest part on my truck. I was hoping for advice other than throw as much money at it as possible. I will however check the ground on the passenger side head

 

Do you mean the wire going from the coil to the distributor center tower? If it's showing signs of arcing out, it's bad, and should be replaced. Generally, it's a good idea to replace the plug wires, including that center wire, every few years, as part and parcel of a normal tune up. Same for the plugs, and the distributor cap and rotor. Using quality OEM parts for this kind of thing is just a good policy. They're not all that expensive. Make sure the o-ring on the distributor cap is in good shape.

A good, quick, and easy way to check for arcing is to look into the engine compartment at night, away from external lights. You WILL be able to see what's arcing, and to where. Clearly. It'll be a great help trouble shooting such kinds of problems.

Good luck!
​​​​​​​Pat☺

 

Getting great advice. I'd only add the TPS is CRITICAL!!!
that's the one thing on these motors I do by the book. Take off the throttle body and set it EXACTLY like it supposed to be set. You'll only have issues, if you don't.
If you Google TPS adjustment You'll find a number of very helpful videos or sites with step by step instructions.