Hi, I bought an 85 318i a few weeks ago to replace my now immobile saab 9000... first bmw, but know these and other cars a bit from working with mechanic friend who's a specialist in european motors.
anyway, the problem is this: car runs normally after starting, but after it warms up a bit (say 5 mins) it then starts to have what i describe as a 'hiccup', rather severely...
symproms are the car intermitently either not firing or having a fuel delivery (mixture?) problem, and the result is jerky power (if idling will idle 'normally', with the hiccups occurring appx. every 1-2 seconds, which causes the tach to appear to jump quickly to a higher idle for a split second, then back down. when running, the tach speed appears to go down...
even when this annoyance is happening, it's got decent power and so forth.
oh yeah, the last guy who worked on it (and gave up) left the throttle position sensor (?) cable assy disconnected... the one to the firewall under the intake manifold... when i re-attach it, the 'mpg' display on the dash pretty much stays up past '40mph' (ha!), even whilst idling, and the idle's all over the place!
i'm not set up too well to work on cars here in fairbanks, so haven't done any testing myself, but the previous owner had it in thew shop off/on for the similar problem. the good thing is that the car's had a lot of basic service in the past coupla years... new idle valve, plugs and wires, cap and rotor, airflow (mass?) sensor, and also a head and oilpan gasket job, also valves. the various vacuum hoses were also replaced, and look good.
well, i'm taking it into the shop monday, but as i'm new to this town, don't know the emchanic, and of the last 2 places that did work before the car was mine, one closed, and the other gave up (gave up?? what the hell is that). so, i'm looking for ideas/advice to feed the mech if he gets confused or to help me if i've got to do trhe job myself!
one idea is possibly the distributor itself, though there might be more to this problem...
so, i paid $1000 for this car, and despite this problem, i like the car and see the possibility to get quite a bit of life (and fun) out of it. i knew the problem when i bought it, and am convinced that if i can just get a competent mechanic, it's easily fixable...
i need your ideas on this, people! thanks!
auto at rjl . us
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