1987 300E Surging IDLE
#1
1987 300E Surging IDLE
OK, i have a 1987 300E 3.0 that i recently purchased with bad fuel pumps. I replaced them with a good used set and was able to get the car running. It had a bad miss and had almost no power. I tracked this problem down to a blown fuse in the OVP Relay. Car ran great for about 300 miles.
1st issue is as follows:
Today I went out to start it and it won't idle. It surges from about 500 rpm to 1500rpm whether in gear or not so i don't want to drive it till i get the issue figured out. I would also like to mention that the car is "cold natured" and by that i mean that when started it has to sit and idle for a few mins before u can push the throttle down or it just dies... And after warmed up it is a nightmare to get started back up. When it finally starts it sputters for a min with usually a nice cloud of smoke then runs ok. But now like i said i have this idle surge and don't want to drive it till i get it resolved and would also like to figure out why it is so hard to get started..
The second issue is just minor but i have an after market radio wired up but for some reason i am not getting power to the 12+ switched wire. The constant wire is getting power. Any suggestions. The fuse for radio appears to be good so im wondering if theres anything else. I would like to say the reason i replaced the radio is i wasn;t getting any sound out of the oem radio and when i turned it on it ran for a bit then just shut off and couldnt get it to turn back on. The sunroof doesn't work as well so im thinking the problems may be tied together??
The car had been sitting for a year or so i'm trying to get the bugs worked out so ill have a nice winter car. Thanks for any advice!!
1st issue is as follows:
Today I went out to start it and it won't idle. It surges from about 500 rpm to 1500rpm whether in gear or not so i don't want to drive it till i get the issue figured out. I would also like to mention that the car is "cold natured" and by that i mean that when started it has to sit and idle for a few mins before u can push the throttle down or it just dies... And after warmed up it is a nightmare to get started back up. When it finally starts it sputters for a min with usually a nice cloud of smoke then runs ok. But now like i said i have this idle surge and don't want to drive it till i get it resolved and would also like to figure out why it is so hard to get started..
The second issue is just minor but i have an after market radio wired up but for some reason i am not getting power to the 12+ switched wire. The constant wire is getting power. Any suggestions. The fuse for radio appears to be good so im wondering if theres anything else. I would like to say the reason i replaced the radio is i wasn;t getting any sound out of the oem radio and when i turned it on it ran for a bit then just shut off and couldnt get it to turn back on. The sunroof doesn't work as well so im thinking the problems may be tied together??
The car had been sitting for a year or so i'm trying to get the bugs worked out so ill have a nice winter car. Thanks for any advice!!
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#2
Junior Member
one problem could be the used pumps you put on it.when you take a used pump off a car and it sits on a shelf until someone buys it , the fuel that is left inside it turns to a thick, sticky ,tarnish like substance that will not just wash out.so when you try to use the pump again it can not reach the rpm's it has to reach to pump the fuel properly.the fuel pressure regulator and or filter could also be the culprit.As far as the radio goes, change the fuse.mine went out on the switched side and the fuse looked just fine , but needed replaced all the same.