91 318is. Cold start it idles at 2k and stays for about 30 secs, Then it surges from 1k to 1.6k, the engine light is on and I checked it with an obd1 scan tool and the only code was an o2 fault. I have ran m42 without o2's before and all it did was rumble not surge, any ideas?
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91 318is M50 swap
89 325ic
12 WRX Daily
86 325e Sold
88 325is (Parted out)
06 330XI (Sold)
91 318is-M20 turbo Sold :(
91 318ic (Sold)
87 528e (Sold)
93 318is E36 (Parted out)
92 325ic (Parted out)
94 325i E36 (Sold)
88 325ix (Sold)
Click my Signature to see the build!!^ -
Have you checked to make sure you have no vacuum leaks? No holes in the intake boot? Cleaned your Idle Control Valve(ICV)? (Seafoam and a toothbrush worked for me.)
Double and triple check these things, and make sure everything is hooked up properly to your throttle body.. if I were you, I would get eyes and hands on every hose that is intake related.. something could be cracked and letting in/out a small bit of air, and it will throw off your idle. -
When I got it a few weeks ago the idle was low and running like crap, i did the valve cover gasket and spark plugs, then pulled the intake off cleaned it from the inside out. replaced all the hoses I could see. took the icv off cleaned the hell out of it replaced those hoses. I seafoamed it as well, i switched Vaf sensors just to be sure, i keep spraying starting fluid everywhere and can't find a leak, loosing my mind trying to figure it out!
91 318is M50 swap
89 325ic
12 WRX Daily
86 325e Sold
88 325is (Parted out)
06 330XI (Sold)
91 318is-M20 turbo Sold :(
91 318ic (Sold)
87 528e (Sold)
93 318is E36 (Parted out)
92 325ic (Parted out)
94 325i E36 (Sold)
88 325ix (Sold)
Click my Signature to see the build!!^Comment
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Dude, I was the same way.. took me well over a year to sort out my idle. I pretty much just broke down and replaced damn near everything that has to do with intake/fuel/spark related.. have you checked your intake manifold gasket? Mine was completely destroyed and was missing big chunks.. hardly enough to make a good seal.
It could be your AFM, but I would definitely check those other things before you worry about replacing your AFM.
EDIT: Also, I'm from Braintree.. have family in Brockton.Comment
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I have a 3 spare AFM's and switch all of them out just to be sure, I have a new intake gasket and torqued the bolts. I'll keep trying, i'm bound to figure it out sometime.
Nice Braintree is where it's at!
91 318is M50 swap
89 325ic
12 WRX Daily
86 325e Sold
88 325is (Parted out)
06 330XI (Sold)
91 318is-M20 turbo Sold :(
91 318ic (Sold)
87 528e (Sold)
93 318is E36 (Parted out)
92 325ic (Parted out)
94 325i E36 (Sold)
88 325ix (Sold)
Click my Signature to see the build!!^Comment
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Yeah man.. the problem is that these idle issues with the M42 are resolved over time, and you're always scratching your head at what works and what didn't work.
I didn't do things "one at a time" because it'd be way too time consuming, and there are so many things that could cause the idle problem.. you'll get it eventually.
Are you running a chip? If so, it may require a certain octane of fuel to run properly.Comment
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