lower idle after long run

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cpalmer
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Joined: Sat Feb 28, 2009 9:58 pm
Location: Portland, Oregon

lower idle after long run

Post by cpalmer »

It's Spring, and I've done enough work on Sophie to make her a DD....almost. I've noticed that after 50 or so miles, she idles lower, and real quiet....600 to 800. Still purring, but I am wondering, a little sluggish when down there off the line. Some of you know I recently fixed a huge exhaust problem on the pipes and before that had messed with the throttle adjustment and timing, which I am now going to check.....it's all close....I think I may have unadjusted things before maybe as I definitely have better compression and mileage since I fixed the exhaust and may have set things out of place. I really don't want her dropping bellow 800 in city type area's.

Thanks!
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Mike W.
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Post by Mike W. »

Check the fuel pressure. It can affect idle speed hot and cold.
Mike W.



02 525ita. Wife's, aka grocery getter
02 530i. New to the fleet, 3 pedals.
03 QX4, AKA the Datsun. Finally got the 4WD vacationmoble to stop smoking.
07 Xterra. Still on the DL, a purchase from hell.
Tomslide
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Post by Tomslide »

sounds like a fuel issue. dying fuel pump or possible rich mixture.
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John in Simi Valley
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Not so Low

Post by John in Simi Valley »

Actually, idle speed of 600-800 is about right.
Not sure if you actually have a problem.
John Savage
1980 528i 5-Speed
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cpalmer
Posts: 141
Joined: Sat Feb 28, 2009 9:58 pm
Location: Portland, Oregon

Post by cpalmer »

Uh, I went to look at it and decided to just turn the afm screw back a half turn.

I'm all okay with it being around 800 rpm, but 600 makes me nervous coming off the line in traffic.

My fuel pump and lines and filter were the first things I did to her when I bought her, so I knew I was good there.

Anyways, it was really low after warm up.......I was about to really think my fuel regulator was toast, but, and a good reason I do not think I am a mechanic in any sense, I looked around, and before I took her for the long drive over the weekend, I checked the oil.....

Well, I didn't put the oil stick back in all the way. It was about an inch out.

Pushed it in and "bingo", all is good. Back at 1,000 rpm.

On this though, I was really confused about the fuel regulator. I couldn't see it anywhere. Where would it be on a 530?

I'm sure it's original as well as the o2 sensor, and a few other sensors that I now realize I need to change. I have been noticing as I drive her more and more, my rpm goes from 1,000 rpm to 800 after the car is hot, it was just horrible it seemed..

I'm off to the corner with a "Derrrrrr" hat on for a few.

Pardon me.
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Mike W.
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Post by Mike W. »

FPR on a 530 is hidden under the intake runners. And your O2 sensor isn't due for a change as you don't have one, they only appeared on 528i's.
Mike W.



02 525ita. Wife's, aka grocery getter
02 530i. New to the fleet, 3 pedals.
03 QX4, AKA the Datsun. Finally got the 4WD vacationmoble to stop smoking.
07 Xterra. Still on the DL, a purchase from hell.
cpalmer
Posts: 141
Joined: Sat Feb 28, 2009 9:58 pm
Location: Portland, Oregon

Post by cpalmer »

Thanks Mike.
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