3-Series (E21, E30)Chat relating to the BMW 3-Series from 1975-1983 and 1984-1991 line. Specific models: BMW 315, BMW 316, BMW 318, BMW 318i, BMW 320/4, BMW 320i, BMW 320/6, BMW 323i, BMW 320i. E30 Family models include: BMW 325e, BMW 325i, BMW 325is, BMW 325ix.
On my '90 325i I have just done a tune up. Plugs, wires, rotor butten, dist cap. I do that on everything I buy used just because you dont know when it was done last. I have noticed a weird idle out of it. It kind of surges at idle and it does it bad enough to make the headlights pulse with the surge. I checked the alternator and batt and everything seems to be ok. Any insight on my problem?
__________________ Current ride. 1990 BMW 325i
It's my project car
Daily driver. 2002 Ford F-250 CC Powerstroke
My drag truck. Not even close to stock.
isn't there something where the engine or computer or something has to "learn" your driving style?
I know in my car whenever I have to un-hook the battery, the first 10-20 miles after hooking the battery back up there's a weird idle.....I've always thought that's the car re-learning my driving style....
After driving a few miles on a warmed up engine...it idles fine...
I might be wrong...and if I am somebody please correct me...
Valves could be adjusted too tight. What gap did you use on the plugs? If you use the small out of the box gap it can cause idle issues. At the shop I work at we use a .032-.034 gap on the M20 and M10 plugs.
Over time, I have found that a bad or out of range coolant temp sensor causes the majority of bad idle/performance problems, the only other item that has a direct effect to the idle but can also leave highway driving performance alone is the throttle position switch. However, the symptoms must be described in full detail in order to find the cause.
Did anyone suggest to check the intake boot for cracks? Or to remove the idle control valve and give it a good cleaning? Or - check and listen for vacuum leaks? All of which WILL effect the IDLE of the car.
__________________ Please visit my website for E30 parts.
On mine it was the TPS. (hard to get too)
(Star Mavin called it right too)
A new AFM helped too. $$$
Not sure if the new temp sensor helped but it was cheap.
Make sure you have all the little metal spring clips for the plastic connectors too, I had to get some from the bone yard for the temp sensor and the AFM connectors, now they dont fall off. LOL
Clean em all with electrical parts cleaner too.
Also, once around the block and my 173 ECU learned enough to handle my new Dinan chip. sweeeeet
(Which I still have 10 copies of, LOL)
'87 325is Delphin Metalic
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