I compiled a list of potential solutions to the DM code 6 (idle speed controller faulty) found on this forum and elsewhere. It is, by no means, not a complete list.

Things to check for high idling:

Try to remove the MAF sensor while the engine running and see if there is any difference and also clean the MAF sensor using MAF cleaner spray.

clean the EGR valve

Vacuum lines near and around the EA missing, loose, not airtight or cracked

Clean the purge regulator in front of engine (remove front chain cover first) The purge regulator is behind the front engine black cover

check the spring on EA and throttle rod to make sure both are intact and in good shape.


Check the RESONANCE IDLE AIR VALVE INTAKE MANIFOLD for electrical wiring connections and the vacuum line connections around the throttle body.

Just for future reference, an idle fluctuation on M104 engines is only caused by one of three problems:

1. a vacum leak

2. a faulty Mass Air Meter

3. a faulty throttle acutator, aka EA / ISC / CC module (Electronic Accelerator, Idle Speed Control, Cruise Control). Throttle Acuators go bad for two reasons. The wirirng harnesses to the throttle actuators has insulation on the wiring that flakes off. This is a problem for 1993-1995 only. Throttle Actuators also have potentioameters that wear out over time.

In some case where clearing DM (pin 3) codes require to go through the clear procedure, then turn ignition off, wait a half a minute or so, then turn igniton back on and check again. You should then get no blinks. You will not get a single blink until you have completed several drive cycles with no faults.

If you have a fluctuating idle, the first thing to check is for a vacum leak as it could be simply a hose that has come disconnected or cracked.


Someone said If the throttle body is clean, but the diagnostics says it is faulty, he still be inclined to remove the whole unit (you would normally have cleaned it from the top without removal) and clean and lube all the linkages and pivots. If it's sticky and tight it will not respond correctly, same scenario.

Another possible solution from someone who had idling issues: Changed the MAF and idle control valve (RESONANCE IDLE AIR VALVE INTAKE MANIFOLD near the throttle body (EA), also changed the fuel pressure sensor and the OVP switch. (Sorry if I had to repeat myself)


These are possible solutions mentioned above. Just throwing in my two cents' worth and hopefully help those who are having these similar issues such as mine. I will go ahead and try these steps and will report my findings. Stay tune for update.