Modern electronics certainly does increase the scope for massive complexity...Thnx very much John,,,
Being a mech engr and running critical projects, learned and preached : 'KISS"[Keep It Simple Stupid !], but these designers now go nuts when told 'The software can do this that and mor e of that'.
Of course a lot of the complexity is forced upon the manufacturers, not just to achieve power with acceptable economy, but also legislated emissions standards.
First I've heard of TB cleaning being associated with any transmission issues. Keep in mind that 'TB cleaning' can mean two rather different things; cleaning the potentiometers as discussed (conductive dirt here causing electronic problems), or cleaning carbon deposits from the butterfly and bore (which will cause airflow issues at / near closed throttle).Help me see any logic in disabling a transmission after the TB is cleaned,,,some damn fault here in TB or there, is sensed....
OK if TB defective is indicated in the code then make the frigging thing easily repairable/re-manufacturable,
Cleaning the TB (by either definition) has nothing to do with the need to 're-manufacture'. Cleaning is only needed for removing deposits from the bore / butterfly, or from the 'tracks' inside the potentiometers. These 'tracks' are what creates the higher or lower resistances (with rotational position) that the electronics rely upon, and can be affected by conductive 'dirt' causing incorrect resistance (and thus an incorrect signal to the ECU)at certain rotational positions by creating un-controlled resistance (or lack of resistance).cleaning the Th Body
ok so when u clnd the TB, ans say results were excellent, do you mean it didnot need remanufacturing ?.,
It's when the internal wiring becomes degraded (disintegrating wire insulation) that 're-manufacturing' becomes necessary, i.e. replacing the affected wires. The rest of the TB is mechanically robust and unlikely to cause problems, for instance the shafts rotate on beautiful little needle roller bearings that I would assume are likely to last effectively forever.
Some people have reported success in coating each affected wire with some sort of insulating compound (painted on?). It would depend on just where the problem occurred, some of the wiring is (somewhat) accessible, but some of each wire length disappears into the guts of the TB and is inaccessible. I think it might be possible to de-solder each individual wire at the accessible potentiometer, then slide a flexible plastic insulating sleeve over the wire length, then re-solder, but I'm sure it would be a significantly fiddly procedure.
I don't know why this would occur, and can't imagine the 'mechanism' that would cause it.In case of 95 I noticed, after cleaning[as many others indicate], the system goes into ;imp mode for transmission, and trans light along with engine light comes on. So its kinda weird that u re cleaning the TB and that leads to not being able to drive the car in reg modes of auto trans. Also it needed mech resetting of throttle cable and toothed disc connection which goes in to a limp mode....and that toothed disc's position is sensed by the electronic sensor.
Reset the ECU and see if the problem recurs.So.....now
1, how do I know that engine light just needs tobe reset, and there is no internal failure in the TB position sensing sytem.
The coolant lines are to heat the TB. As air passes the butterfly there is a restriction to airflow, this causes the speed of flow to increase (but the volume to decrease). As the speed of air flow increases the pressure drops, as the pressure drops the freezing point of water (humidity in the air) increases. So, water (as humidity) that condenses on the cold surfaces (butterfly and bore) can freeze more easily, causing ice deposits that can affect air flow and perhaps even jam the butterfly valve.3. What is that fluid lines, one coming to the TB and other going out of it,,,,re these ..coolant...?
Heating the TB somewhat lessens the likelihood of this happening, which is only likely to happen in very cold / humid conditions (unless you live in a very cold climate it will never happen). It's probably not such a big deal with multi-point port injection, but can be with single point TB injection since evaporating fuel will be passing through the TB, which will further exacerbate temperature decrease in the TB.