Why Does the TPS Keep Needing Adjustment

[CREGAN]

Does anyone know why a TPS would keep slipping out of adjustment? My van was shifting rough 3 days ago so I decided to check the TPS setting since it hasn't been adjusted since I had the fuel pump seals re-done. It was 0.56. So I adjusted it to the optimal 0.78 and it has run well for the past couple days until today it began acting silly again. So I checked it and sure enough it had slipped to 0.69. The screws holding it in place are very tight and it is a new TPS. Any ideas or suggestions because I really don't want to have to keep doing this every week? Not exactly fun when you have solid intercooler pipes. Thanks

Craig

[psilosin]

Its quite likely that your shiny solid intercooler pipes are allowing your intake air to travel so fast and efficiently that, much like inside of the hadron collider, molecules are smashing together with so much force that tiny blackholes are being formed and causing big trouble with your TPS. If I were you I would remove them immediately, bubble wrap them and send them to me for further analysis.

[CREGAN]

Its quite likely that your shiny solid intercooler pipes are allowing your intake air to travel so fast and efficiently that, much like inside of the hadron collider, molecules are smashing together with so much force that tiny blackholes are being formed and causing big trouble with your TPS. If I were you I would remove them immediately, bubble wrap them and send them to me for further analysis.

Interesting. I posed this question to Stephan Hawking (as he is on the british forum under the screen name JumboJugzz) and that is the exact reply he gave me. Maybe I will send one to you and one to him and see if the analysis yields similar results.

Craig

[FalcoColumbarius]

Man! There's a really good screen play in this thread somewhere. Don't forget your towel.

[tonydca]

Does anyone know why a TPS would keep slipping out of adjustment? My van was shifting rough 3 days ago so I decided to check the TPS setting since it hasn't been adjusted since I had the fuel pump seals re-done. It was 0.56. So I adjusted it to the optimal 0.78 and it has run well for the past couple days until today it began acting silly again. So I checked it and sure enough it had slipped to 0.69. The screws holding it in place are very tight and it is a new TPS. Any ideas or suggestions because I really don't want to have to keep doing this every week? Not exactly fun when you have solid intercooler pipes. Thanks

Craig

IIRC, it's only fed 5 V, so it shouldn't matter if your glowplugs are on or not, since the system voltage should *never* get that low.

A bit of a shot in the dark, but the electrical resistance of materials will fluctuate a certain amount with temperature change.

Maybe make sure you get the engine warmed up before you pop off the tubes and check/adjust the voltage.

I've heard it can get cold in Alberta...

[CREGAN]

Yeah I have found out it is best to do it when the engine is warm. I was thinking the temperature may have something to do with it as well as it has been so warm here this winter. I kind of hope that is not the case though as the weather fluctuates quite a bit here. It can go from -30 to +8.

Craig

[jessef]

not the voltage but have you checked the resistance at the 5+ connection? With the engine on and a solid clamp (not moving) on the wire <-> meter, see if it 5V source fluctuates at all. Even if it does a 'bit', that's enough to raise/lower your value at the TPS in which case you can then begin tracing it along the wire (most likely be and old or internally corrosive power wire ~ found this out with Jay a while ago).

[CREGAN]

Jesse- Is it difficult to trace this wire should I need to replace it? How does one go about replacing it? I am going to try this test ou when it warms up later this week. For this test, do I have to clamp the probe into the wire and then put it all back together and fire it up? This could be the solution to a problem that has been plagueing my van since I got it. It would mean that i have a spare TPS now since the other one might have been just fine. Worth a look. Thanks

Craig