Hi I have a 1990 535i, that has developed a jerking/bucking while driving. The car idles great and there is no hesitation when I rev it up in driveway. However, when I start driving the car jerks around 2k rpm. Sometimes, there is also a popping noise from the exhaust. When I floor it, the car goes smooth, but when I gradually bring it to 2k rpm the car bucks back and forth. New cps, dizzy cap and rotor, spark plugs and wires, fuel pump and filter etc.
Any ideas?
Thanks
"popping" from the exhaust would usually have me pointing at the ignition(is coil strong & gaps correct?) but seeing that you've addressed that I'd suspect a lean miss under load, vacuum leak.
If you can leave two black stripes from the exit of one corner to the braking zone of the next, you have enough horsepower. - Mark Donohue
The problem randomly stopped...interesting
problem is intermittent... it is specifically at 2k-2.5k rpm when foot is steady on throttle
Okay, have you checked the ignition system yet?
Do you have a shop manual to tell the values you are looking for?
Last edited by dworthy; 04-18-2019 at 03:40 AM.
Darin
Current:
16 220i Active Tourer Platinsilver MET (C08)/Dakota Black (PDSW), P7ACA, P7LDA, P7LHA, P9BDA, 6sp Manual - Wife's new toy!
05 325it Electric Red(438)/Gray(N6TT) ZCW, ZSP 5sp Manual Back set cover, trunk mat, Euro Infra-Rot front windshield, and mud flaps! Mr. Wagon My new Winter car.
05 M3 Imolarot II(405)/Gray(N5TT) ZCW, ZPP 6sp Manual C.F. Lip, CSL diffuser, SSK, Euro Infra-Rot front windshield and a trunk liner! Mr. Go_Fast Stored for the Winter
Past:
95 318is Montreal Blue Met (297)/Beige(K1SN) RIP, killed by an Idiot.
84 M535i gray market Burgandy Rot Met/Black Leather Lowered by Intrax on bilies, poly everywhere, B&B cat back system, K&N, and a hitch! Da Beast - Still running w/400k+!
91 316i euro Tizianrot/Gray cloth - E-36 w/M-40 RIP, but great on gas! Best was 38 MPG
82 528i euro Saphire Blue Met/Blue Leather RIP
79 525 euro Green/Green RIP
79 318 Silver/Black - The first one that got it all started
M-Flight Member
Suspect a throttle position sensor issue. Look up resistance values for yours and check that 1. they're correct, and 2. they change smoothly through the throttle's range.
Bookmarks