What Could This Be Related To....

[BMW4LIFE]

I notice that sometimes when I press on the gas pedal there is a slight delay then all of a sudden there is the acceleration i was looking for

this usually happens when I am at very low speeds or even from a stop

I have changed the fuel filter about 20K ago
The fuel Pump around 30-40K ago
The air filter around 20-25K ago
The spark plugs around 30K ago (Bosch +4...could that be the problem?)
I use premium gas

any thing else it could be? Any suggestions?

thanks guys!

[ahlem]

Vacuum leak. AFM needs checking. Fuel pressure issue, pump or regulator. gooey injectors.

[BMW4LIFE]

Vacuum leak. AFM needs checking. Fuel pressure issue, pump or regulator. gooey injectors.

EWWW!

that does not sound fun at all!

How do check these issues?

[ArnZ!]

Pretty sure everyone suffers this. Its mainly due to AFM design as its the vane type, which has the little flap that has to open when more air is sucked in. This is an old style way of metering air that goes into the engine, a Miller MAF uses a hot wire which senses the amount of air but with no lag as there is no flap anymore, so maybe investing some money into one of them is a good idea.

[Ferret]

Pretty sure everyone suffers this. Its mainly due to AFM design as its the vane type, which has the little flap that has to open when more air is sucked in. This is an old style way of metering air that goes into the engine, a Miller MAF uses a hot wire which senses the amount of air but with no lag as there is no flap anymore, so maybe investing some money into one of them is a good idea.

His is an M50 motor with wire MAF though, surely?

[BMW4LIFE]

let me ask you guys this... is it worth doing the fllowing;

change plugs
air filter
fuel filter
throw in some injection cleaner (but i use 91 as it is =/ )

[ArnZ!]

His is an M50 motor with wire MAF though, surely?

You sir seem to be correct! sorry BMW4LIFE my comment is only good for the m30 and m20 motors then.

[Ferret]

let me ask you guys this... is it worth doing the fllowing;

change plugs
air filter
fuel filter
throw in some injection cleaner (but i use 91 as it is =/ )

My E31 was stuttering as it came off idle a bit, changed the plugs and it went away...

However it could be a lot of things other than this as well.

Plug change is always worth it :)

[Tiger]

I think it is because of electronic throttle control. The lag. When I stomp on the accelerator... it seemed like 1 second before all hell broke loose in a good way. LOL

[bubba966]

let me ask you guys this... is it worth doing the fllowing;

change plugs
air filter
fuel filter
throw in some injection cleaner (but i use 91 as it is =/ )

Didn't I already tell you to pull out those +4's you've got in there and at least put the proper OE plug in, if you didn't want to give the E3 plugs a go?

Air filter is way past due for a change.

Fuel filter could be changed out by now.

And yeah, I'd go ahead and run a bottle of Techron through the engine. Don't care if you use 91 or not. A little Techron every now and then (or better yet Seafoam in the gas) is good to clean things up a bit.

Would put Techron or Seafoam in the tank, and change plugs right after you fill up with the Techron/gas or Seafoam/gas mixture. That way it'll burn the cleaning mix better. Change the air filter at the same time.

Then once you've gone through the tank with the fuel system cleaner go ahead and change out the fuel filter.

New air & fuel filters as well as new (and proper) plugs will certainly help it run smoother. If it's still a little off then you can start looking at other possible culprits.

[Tiger]

+4 plugs has always been a bad idea... I heard lots of problems when people put them in.

Single electrode is the best... people say engine is even smoother with single electrode rather than the dual that factory use.

[BMW4LIFE]

+4 plugs has always been a bad idea... I heard lots of problems when people put them in.

Single electrode is the best... people say engine is even smoother with single electrode rather than the dual that factory use.

hmmm...

I have a feeling that I might be going to the OEM plugs...

Bubba I want to thank you for all your help and advice put I don't know if I can gamble with $40 to find out there was no improvement and the OEM were still better...

I am sad that the +4 are so crappy because they are the only plugs that I have used since I bought the car in 2001...

Now I feel like a dumb ass

[BennyM]

I'm leaning towards Tiger's thoughts. However, the throttle control on your car is not actually electronic. It still has a physical cable connected to the pedal. You might want to check the throttle position sensor. Disconnect it from the harness and test the resistance as you open it. There might be a dead spot, which could momentarily confuse the engine control module.


I think it is because of electronic throttle control. The lag. When I stomp on the accelerator... it seemed like 1 second before all hell broke loose in a good way. LOL

[bubba966]

+4 plugs has always been a bad idea... I heard lots of problems when people put them in.

Single electrode is the best... people say engine is even smoother with single electrode rather than the dual that factory use.

Single ground strap (not single electrode as the electrode is in the center of the plug) might work better if using an iridium plug. But a standard style single ground strap plug runs just as bad as the +2 & +4 style plugs do.

Have tried single ground strap standard style plugs as well as the + style plugs and neither were any good. Wasn't going to spend $12/each on iridium plugs to see if they worked or not when I need 8 of them.

M60's & M50's work well with ground straps that come up along side the center electrode, not over top like a single ground strap or + style plug. And that is why I decided to give the E3's a shot as their ground strap is also a side mounted in relation to the electrode style plug. But the E3's have a very unique ground strap. And they work rather well in M60's & M50's in my experience.

[Tiger]

I have used E3 on chainsaw... it starts up real easy.