Still Suffering from hesitation/bucking even after VANOS seals? Look Inside!

I have horrible bucking in 1st gear in my '01. i just did this tonight on my connectors. will report back.

I'm definitely going to try this. had a tab bit of bucking first gear, on occasion; maybe this is what i need to do.

i wonder where I could get electrical cleaner (locally)? Gamestop? lol, idk.

Try your local automotive shop and ask for CRC contact cleaner.

Originally Posted by Tarmac_E46_M3

I'm definitely going to try this. had a tab bit of bucking first gear, on occasion; maybe this is what i need to do.

i wonder where I could get electrical cleaner (locally)? Gamestop? lol, idk.

did this quick fix this morning... I was sceptical as hell, but said what the heck, its a free mod right? Im still not 100% sure if I feel the difference, I had bucking even after I did the VANOS rebuild. I THINK I still feel the bucking, but it seems to be less. I'll post my final determination after a couple days of driving.

Check out coils

Don't forget the basics too...fuel filter, Techron, driving wot occasionally. Bucking sounds like it wants more gas than it's getting. If it's not an intake leak, which I'm sure you all checked, it could be clogged injectors or fuel filter...could be a batch of bad gas too.

Can someone post pics where all these plugs are?

Maf is most obvious(on the intake), but other than that, I'm lost.

I get that bucking more and more every couple days.

Lastly, where can I pick up the salmon relay and where is it located?

Originally Posted by Tarmac_E46_M3

Can someone post pics where all these plugs are?

Maf is most obvious(on the intake), but other than that, I'm lost.

I get that bucking more and more every couple days.

Lastly, where can I pick up the salmon relay and where is it located?

You need to take the intake manifold on the M3's, then all the connectors are in plain sight. Simply disconnect and crimp the ones that have the same style plug as the ones pictured.

look up DIY's for both the intake and exhaust camshaft sensors for M3's to find out where to find those.

Oh, ok! Cool. I'll be taking that off tomorrow then... gives me something to do!

thanks

EXCELLENT info... I had planned on repairing my VCG in early Spring, when it warms up. I have spent DAYS reading and re-reading this forum... You guys are awesome. But I keep seeing stuff I need to fix!

I do have a mildly fluctuating idle so I figure I might as well do the Vanos seal repair while I am replacing the VCG. Then reading up on that and its related threads and posts lured me here. Great info!

So it looks like a complete tune up, clean the ICV, replace Vanos seals, VCG, plugs and tweak the connectors. I wish it was 70 degrees out in the garage... I'd be out there now.

I had a little bit of a hiccup at idle at 80K miles and added in the Vanos seals and rattle when I did my VCG (which incidentally was in like new shape when removed). After this work, I can still get a bit of fluctuation in idle speed. So there are no guarantees.
Always post your mileage so we have some idea of where your engine is in its history.

Originally Posted by Big Rick

EXCELLENT info... I had planned on repairing my VCG in early Spring, when it warms up. I have spent DAYS reading and re-reading this forum... You guys are awesome. But I keep seeing stuff I need to fix!

I do have a mildly fluctuating idle so I figure I might as well do the Vanos seal repair while I am replacing the VCG. Then reading up on that and its related threads and posts lured me here. Great info!

So it looks like a complete tune up, clean the ICV, replace Vanos seals, VCG, plugs and tweak the connectors. I wish it was 70 degrees out in the garage... I'd be out there now.

Originally Posted by Stinger9

I had a little bit of a hiccup at idle at 80K miles and added in the Vanos seals and rattle when I did my VCG (which incidentally was in like new shape when removed). After this work, I can still get a bit of fluctuation in idle speed. So there are no guarantees.
Always post your mileage so we have some idea of where your engine is in its history.

FWIW, My 330ci has absolutely no idle fluctuations and killer engine response.

Originally Posted by odgamma15

did this quick fix this morning... I was sceptical as hell, but said what the heck, its a free mod right? Im still not 100% sure if I feel the difference, I had bucking even after I did the VANOS rebuild. I THINK I still feel the bucking, but it seems to be less. I'll post my final determination after a couple days of driving.

OK, Ive driven for a few days and can confirm it did not help me... Well, I hope it works for others!

Originally Posted by Big Rick

EXCELLENT info... I had planned on repairing my VCG in early Spring, when it warms up. I have spent DAYS reading and re-reading this forum... You guys are awesome. But I keep seeing stuff I need to fix!

I do have a mildly fluctuating idle so I figure I might as well do the Vanos seal repair while I am replacing the VCG. Then reading up on that and its related threads and posts lured me here. Great info!

So it looks like a complete tune up, clean the ICV, replace Vanos seals, VCG, plugs and tweak the connectors. I wish it was 70 degrees out in the garage... I'd be out there now.

Make sure your oil cap isn't leaking. My M3's was and it was throwing everything off.

I have A 2001 325I with 190,00 miles on it. I did the VANOS seals last summer and it did not solve the surging that I see when I get up in RPM's (above 3000). I will try using contact cleaner and crimping this weekend and report back.

I have a manual with 87K.
When partial throttle above 3K rpm, my car stutters, with erratic power slightly, but in an annoying fashion. Full throttle usually pulls strongly and evenly.
Is this what you have?
When did you last do plugs?
I did full vanos, injectors, O2 sensors, and camshaft position sensors, and fuel pump and filter without effect.

Originally Posted by beauch3

I have A 2001 325I with 190,00 miles on it. I did the VANOS seals last summer and it did not solve the surging that I see when I get up in RPM's (above 3000). I will try using contact cleaner and crimping this weekend and report back.

Plugs and valve cover gasket were changed about 5000 miles ago. I pulled the one plug off of the vanos and used contact cleaner. I drove after that and it ran great. Couple of days later the problem came back however. It seems to be intermittent. When I have it, it is more than a slight stutter. I have not pulled the DISA yet. Anyone have these symptoms with a bad DISA?

Originally Posted by beauch3

Plugs and valve cover gasket were changed about 5000 miles ago. I pulled the one plug off of the vanos and used contact cleaner. I drove after that and it ran great. Couple of days later the problem came back however. It seems to be intermittent. When I have it, it is more than a slight stutter. I have not pulled the DISA yet. Anyone have these symptoms with a bad DISA?

You need to do it to ALL connectors. And not just one half assing the job. I can't stress this enough.

For what it's worth, the Bosch style connectors primarily used in our application are also used in a bunch of other vehicles... like Ferraris. Older Ferraris have a cheaper version of these connectors, which are only specified to maintain a good connection for around 5 removal/installation cycles. Once they have been plugged in and unplugged more than a few times, the contacts will loosen up, and then Jorge/George's procedure will fix them temporarily, with the added bonus of using easily corroding metals for the contacts. I wouldn't bother unplugging all the connectors to check this out unless you have to anyway for some maintenance work.

I know this thread has been going on for a long time but I'd like to say top dollar to the guy who posted about cleaning the connectors!

I cleaned and crimped the vanos exhaust connector and camshaft connector as they were next to each other and it has made a big difference. from 1,500 to 3,000 rpm the pull has increased a lot and the engine runs much smoother through the rpm range. The engine note has changed as when you floor it now it doesn't get bogged down, just sounds a lot more free'er flowing. I also think gear changes are less clunkier and smoother (might be in my head though that). Car has had 100 miles covered since diy. I'll be tackling the intake vanos connector this weekend.

Not left car running upon first start up to see if it has cured the irratic idle when cold. will try tomorrow morning I think.

Just to let people know how much work I have done on my car to solve the low end torque issue:- cleaned all intake, maf sensor, ICV (twice), Camshaft sensor (intake), TB, has B25 inlet manifold mod (increasd power top end), spark plugs, new fuel filter, new juel pump.

Fingers crossed this has worked, not checked mpg yet.

Dan