No power to vanos solenoid? But no vanos code?

[GeTReKtA]

[1997 328i]
I’ve been trying to diagnose my poor throttle response and bogging from idle to about 3k and noticed my crank sensor wiring harness (the one that connects to the vanos solenoid and a few other sensors) seems burnt through in some spots. The wires inside seem to be intact but I decided to test the vanos solenoid by unplugging it with the engine running and giving it a few test revs before and after. I noticed no difference with the vanos solenoid plugged/unplugged.
If the wiring harness was damaged and my vanos solenoid was receiving little to no voltage then why would it not give me a diagnostic code?
If vanos was completely disabled would it make the car want to stall when moving from a stop? I also get bucking when cruising around 3k and have to cruise above it to avoid bucking and almost stalling.

[bmwdirtracer]

No, the vanos being completely disabled would have zero effect when moving from a stop. That sounds very much like an intake system leak, or other fuel/air mixture issue. Of course,some of those "other sensors" might be, say, temp sensors, which, if giving incorrect readings, would certainly cause incorrect fuel/air mixture issues, and your behavior.

What are you using to read codes? You need a good BMW specific scan tool which can also read live data, like intake air temp, air flow, engine coolant temp, O2 sensors, etc.

A smoke test of the intake system would be a very good idea.

[shadowpuck]

All the same car, all the same issues.

mods - can we merge threads please?

op - this is going to be much easier to help you if you keep all the info in one thread.

https://www.bimmerforums.com/forum/s...le-and-jittery

[bmwdirtracer]

All the same car, all the same issues.

mods - can we merge threads please?

op - this is going to be much easier to help you if you keep all the info in one thread.

https://www.bimmerforums.com/forum/s...le-and-jittery

Thank you, shadowpuck, for leading me to the rest of the information.

GRRRRR!
Getwrecked: You are making it very difficult for people to help you. Keep your $#!+ in piles.

[GeTReKtA]

Thank you, shadowpuck, for leading me to the rest of the information.

GRRRRR!
Getwrecked: You are making it very difficult for people to help you. Keep your $#!+ in piles.

I’ll try keeping it all in this thread from now on

[GeTReKtA]

Update:

Checked the coils with a volt meter and they all read around 1.2 ohms. I also checked my old Bremi coils and they read around 0.9 ohms. Swapping coils is one of the few things I haven’t tried since I wasn’t getting codes for them and the symptoms didn’t seem like coils but I’ll swap them later and see if it makes a difference.

- - - Updated - - -

Using bmw logger the only real codes I got are mixture deviation on banks 1 and 2, and Lambda Regulation Bank 2 Pre Cat which is weird since I just put brand new o2’s in.

Using my cheap obdII scanner I got P0121 for tps but that might just be because I swapped tps to test it and put the old one back on afterwards.

[bmwdirtracer]

Get a smoke test of the intake/CCV system. Every symptom, and your codes, point to a large intake/ccv leak.

[GeTReKtA]

I’ve removed my ccv system entirely and done multiple amateur smoke tests by blowing smoke through a hose. If there is any intake leak, it is so small that I couldn’t find it with a smoke test.

[bmwdirtracer]

Blowing smoke through a hose is not a smoke test. A smoke test depends on pressurized, thick, cloying smoke for an extended duration. There are not enough rastafarians to equal a smoke machine.

AND, I'd likely guess that the removal of the CCV system might well be the source of your issue. Just a guess, but the last couple of examples I saw of this "MOD" were blatant mistakes.

[GeTReKtA]

IÂ’m back with an update on this car and IÂ’m losing all hope.

Currently, symptoms are:

Long cold start cranks (about 5 seconds or longer)

Extreme rev hang, I have to wait around 3 seconds for the revs to drop enough to shift comfortably.

If IÂ’m heavy on the throttle above 3.5k rpm then the rev hang instead seems like a misfire and the rpm will drop dramatically fast.

Inpa shows up to 6 degrees of knock retard. A tap of the throttle at idle will retard about 1 degree and attempting to accelerate at any point above that will retard anywhere from 1-6 degrees.

Idle is solid. Not a single hiccup, perfect idle.



I just had the injectors professionally cleaned and it made no difference. My friend with the same car has the same setup without the ccv and his car runs perfectly fine.

IÂ’ve inspected every inch of the entire intake system as well as spray brake cleaner around to look for leaks and IÂ’m positive there are none.

The throttle body is clean and the throttle linkage is good.


The car feels dangerously slow and having to drive this thing to work everyday is severely depressing considering IÂ’ve thrown hundreds in parts at it and itÂ’s only gotten worse as time goes on.

The ONLY code is evap solenoid and I doubt that would make the car this undrivable.