TCC Solenoid problem on 1994 Silhouette

Bad spark plug wires.

I used two paper clips to insert into the connector from behind (backprobing?). One where the blue wire is (in the middle) and one where the black wire is (the ground). Turn the ignition on, but don't start the car, and read the reference voltage (mine is 0.36V). There are two screws that attach the TPS to the throttle body which are harder then hell to get at, but you need to loosen them up and, watching the voltmeter rotate the TPS until you get the correct voltage for idle. Tighten down the screws, then check the range of voltage for the TPS. I believe that you need > 4.5V for WOT. Since I don't plan on hammering on this van, WOT isn't a real issue for me.

If you really want to get it perfect, you might have to actually remove the TPS and wallow out the mounting holes to get the correct voltages both at idle and at WOT. (It took me 10-15 attempts on my 1987 GN to get both the correct idle TPS voltage, and the correct WOT).

HTH, Bill

n> For my own information, but how are you going to reset TPS voltage? I have

I changed the spark plug wires about a month prior to the transmission being replaced. I have only owned this van for about four months now, and this van has never done this 'clunking' until the transmission was replaced.

I'm still leaning toward the TCC solenoid.

Bill

It's possible that the TCC is slipping (in which case you've got a bad rebuilt trans), but this is quite possibly nothing to do with the transmission at all. If you have any kind of misfire or ignition voltage leakage problem, then higher throttle openings with the TCC locked is when you're most likely to notice it.

Unless you're pretty heavily into the gas, the TCC should be staying locked, so I'm doubtful that it's anything to do with the TPS, etc.

Robert,

I normally would tend to agree with you, but the spark plugs and wires are only two months old. Prior to the old transmission taking a crap, you would think that these symptoms would have showed up. It just seems too coincidental that it just starts happening when a rebuilt tranny is installed.

I set the TPS to 0.48V to appease the tranny shop, now I will have them test ride it again, with the scan tool hooked up. This is a definite clunking, not an ignition related issue.

In a previous vehicle (1994 Buick PA), I have experienced the ignition problem. It's more of a miss/hesitation with the plug and plug wires were bad. This time it is like it is trying to downshift and upshift at the same time causing the clunk (almost like the tranny or engine mounts weren't tightened). If it ever warms up, I would actually get under it and check all of the mounts myself.

Thanks for you help. Bill

Just an update,

I took it back to the tranny shop after adjusting the TPS. A different person went on a test drive, and said he had never experienced this type of shudder. He thinks it is the drive chain that is loose and is slipping (or something mechanical). I have an appointment to take it in on Friday. They will look at it, but will most likely just replace it, then tear down the one out of my van to figure out what is happening.

Thanks for all the help. Bill