Cleaning the Throttle Body of a 1993 Bonneville SE
Flat-blade or Phillips screwdriver
½" or 13mm socket + Ratchet
Watered-down Orange Clean concentrate
Fine- or medium-tip permanent marker (e.g. Sharpie)
Small wire brush
Disassembly and Cleaning
1. Start by removing the Throttle Body (TB) from the Intake Manifold.
2. Remove the MAF screen if you haven't already done so (directions in Techinfo under http://www.bonnevilleclub.com/techinfo/?article=40
3. Remove the Throttle Position Sensor (TPS). If you are going to reuse the old TPS, make an alignment mark between the TPS and Throttle Body.
4. Next, remove the MAF sensor. BE VERY CAREFUL: if you break the delicate little wires in it, you will pay big-time for a replacement.
5. Remove the Idle Air Control Valve (IAC) and remove the o-ring.
6. (Optional) Remove the choke flap by unscrewing the two screws that hold it in, then open the throttle valve to pull out the flap. Remember which side goes out!
7. Using the toothbrush and gasoline, scrub the inside of the TB, and rinse occasionally with the Orange cleaner or water to remove the dirty gasoline. Scrub the choke flap until it'* clean. Be sure to clean down in the holes for the MAF sensor and IAC.
8. IMPORTANT! Blow out TB with air hose to ensure that all moisture is out of the IAC and MAF sensor housings, along with the rest of the assembly.
9. (Optional) Use the small wire brush to clean the outside of the TB; it just makes it look pretty.
1. Put the choke flap back in with the same side facing out, like it was when you started.
2. Reinstall the MAF sensor, being very careful not to break the delicate wires inside.
3. Measure the IAC valve from the tip to the gasket mounting surface. It should be less then 1 1/8". If it isn't, figure out which IAC you have and adjust accordingly.
4. Reinstall the TPS, making sure to line up the alignment marks you made earlier.
5. Reinstall the MAF screen if you removed it during disassembly.
6. Put in new gasket between TB and intake manifold.
7. Finally, bolt on your newly-clean and hopefully better-working Throttle Body.
This job will take about 1 hour to complete, depending on how clean you want it to be.