m42 idle surges

[bucksworld]

I think i need a new/used mass air flow sensor. Part # 0280202134. The boot looks in good shape. There is just an adaptor and filter. The prior owner added this cheap air intake setup for around $10bucks. The car will rpm between 500-950 at stop lights from time-to-time. No check engine light.
Am I on the right track? Anyone no what to do?

[Panzer_M]

Idle Control Valve, I would say is to blame for a idle issue.

[bucksworld]

no, I should have stated I tried some things and that was one of them. A complete tuneup was done; new plugs,wires,idle sensor, fuel filter battery, alternator. All this was done a few months ago when I bought the car used w/136,000mi. The dealer put an o2 sensor because it was a recall issue. I hoped it would help with this issue but it did not and he said something about the cyl head cam needs adjustment. I didn't think that made sense so left quickly......

[jkilla71]

Originally Posted by bucksworld

no, I should have stated I tried some things and that was one of them. A complete tuneup was done; new plugs,wires,idle sensor, fuel filter battery, alternator. All this was done a few months ago when I bought the car used w/136,000mi. The dealer put an o2 sensor because it was a recall issue. I hoped it would help with this issue but it did not and he said something about the cyl head cam needs adjustment. I didn't think that made sense so left quickly......

I just installed a K&N-57i filter today and the same thing is happening to me. The car ran fine before I took out the air box. Now it hardly stays running or some times I will start it and the engine light will come on and it will idle prefect then if I rev it up the light goes off and it idles rough. I am putting the old M42 air box on tomorrow morning. Too bad it sounds great when you jump on it.

[bucksworld]

yes, i wonder if these upgrades can damage the air mass meter 0280202134 ?
but I think I'll try a new air intake systems. i found a used air mas meter for $90.00 but I'll wait on that part.

[campaiar]

The K&N filters can definitely be bad news to the intake sensors.

Since a K&N does its filtering through oil, that oil is slowly drawed into the engine through the MAF sensor. That's why you have to "recharge" a K&N, basically replace the lost oil in the filter material.

[bucksworld]

OK Thanks.............I 'LL stay away from them; however looking at the cosmo intake system as an upgrade. Its the only one the fits the m42 1.8l.

[jkilla71]

Originally Posted by bucksworld

yes, i wonder if these upgrades can damage the air mass meter 0280202134 ?
but I think I'll try a new air intake systems. i found a used air mas meter for $90.00 but I'll wait on that part.

I was going to put the stock M42 air box in this morning but after inspecting the intake boot attached to the MAF I noticed a nice crack in the boot between the ridges. I must have damaged it when installing the K&N 571 filter kit. I gave the good folks at Lauderdale Imports Ltd-BMW a call and the had the boot in-stock (34.95). I installed the new boot and she idles and sounds great.

Good luck with yours!

[campaiar]

Clean the Idle Control Valve like Panzer suggested first. Then you can make your CAI decision.

Putting aftermarket parts on to fix problems can get really complicated if other issues are introduced.

[bucksworld]

Idle control valve was replaced from the get-go. Two screws out it comes and in goes a new one for 80bucks. no help. I did clean the current cone filter and noticed a improvement. I cannot go back to stock intake box however because i don't have it. I bought car as is; all stock intake is gone. I am looking at a cold intake to fix this problem. The engine sure runs good considering idle issue. Can take it past 100mi per hour with ease. Still looking at cosmo cai for 120bucks............thanks

[jkilla71]

Originally Posted by bucksworld

Idle control valve was replaced from the get-go. Two screws out it comes and in goes a new one for 80bucks. no help. I did clean the current cone filter and noticed a improvement. I cannot go back to stock intake box however because i don't have it. I bought car as is; all stock intake is gone. I am looking at a cold intake to fix this problem. The engine sure runs good considering idle issue. Can take it past 100mi per hour with ease. Still looking at cosmo cai for 120bucks............thanks

I just got the basic K&N kit for the 318ti from http://www.4filters.com/ for 77.00 and free shipping.
Just plug in the year make and model.
The Filter kit # is 57i
fits nice

I am thinking it is the MAF sensor too. The prior owner may have not cleaned and oiled the filter regularly getting some debris in the MAF

Even thought these filters require some attention the car sounds and runs smooth with the bosal exhaust

Good Luck!

[mooseheadm5]

Check for a vacuum leak. The breather hoses are the first suspect. Cars with vac leaks often idle poorly but accelerate fine because the ratio of unmetered air to metered air is much smaller under load. OBDI cars with vac leaks rarely set CEL.
My $0.02
-Paul

[bucksworld]

No leaks found..............Thanks anyway

[campaiar]

If your interested in an original airbox I've got one off my 1995 (Just finished my engine swap) Its already loaded with a K&N. I've got a recharge kit too.

I can send along my old MAF too if you want it. There is a write-up on how to "Fogg" the stock airbox for better performance too.

[bucksworld]

Thanks...I'll give it some thought....