My younger brother just bought a 91 Cressida a few weeks ago. Anyway he got a new stereo installed and now whenever the engine is at operating temperature the idle drops to about 5-600rpm and the car shaked when you tried to take off.
I thought the stereo system must be drawing current and hence more load on the alternator and cause the rpm to drop, like when I turn on my headlight in the Sprinter. So I turn off the stereo but it didn't make any different. So what is going on? does the amp in a stereo system constantly drawing current even when you haven't got the stereo on? dodgy wiring?
Where is the idle adjustment on the engine its a 7MGE i think. What is the recommended engine oil to use? we haven't got a handbook with car.
Its possible that the battery was nearly dead, ie its holding sweet FA charge these days. Put in a stereo and she really struggles when ur engine aint doing enough revs for the alternator to bt fully supporting everything. Hence the low idle. If this is the case, adjusting idle will only mask the symptom. That is; pump in heaps of extra air & fuel to compensate for half a spark...??? not a good solution for my mind...
Go to a batteryworld or something and see if they think it could be the cause. In saying that, dont walk in asking to hand over your money, get them to justify replacing it too!