Hello All;
First time posting here, the folks at mbz.org sent me this way when I asked about their listserve...

Anyway, as the title says I've got a 1987 300SDL with about 206K miles on it. I live in the high dessert of Cal., lately it's been about 100-105F ambient, lots of sun.
I'm having a couple of problems, maybe three and they may be related, maybe not. I did some searching on the forums today and couldn't find anything that seemed to help so I thought I'd ask if anyone else has experienced these issues, here goes;

1) Sometimes when the car is first started during the day the idle will surge at first, it then returns to the normal 600 rpm. It used to be infrequent but now it's happening more and more according to my wife, who is the main driver.

2) Next issue. When returning from down south this last weekend we had a couple of instances where the rpm gauge stopped working and the a/c cut out as well. We stopped so that I could check the fuses, I found nothing wrong with them. After few minutes we started up the car and everything worked ok. About 20 minutes later the same thing happened again, but we were 20 minutes from so we continued on in the 105F heat (but it's a dry heat, as everyone says...). The first time it happened at a stop light, the second time it happened we were going about 65 mph. It seemed like the engine rpms fell a bit when the gauge stopped working but this is most probably my mental reaction to something not working. To compound matters, my wife tells me that this has been happening over the last few weeks, but she's never mentioned it since most of her trips are short and she doesn't use the a/c for those trips anyway.

So, that's what's going on. Has anyone ever had this happen to thier benz? Does it sound like there's a relation between the two problems? Any suggestions for fixing either issue would be greatly appreciated.

Thanks in advance,

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