Help Please Got A Problem

[d3s3rt]

Hi everyone im new to this forum. i just got a 1998 528i and i have my first problem its a 5 spd and i noticed when i shift gears the motor continues to rev between the shifts or when im at the lights and i tap the gas pedal the motor revs up and stays up and sometimes it comes down after a minute. Does anyone know of this problem, and if it is a vacuum leak. Any help or advice anyone can offer me I would be very grateful and thankful.

[Torque]

bad throttle cable ?

i guess we can wait for e39 experts to come in give them a few minutes.

[d3s3rt]

Originally posted by Torque@Dec 14 2004, 04:29 PM
bad throttle cable ?

i guess we can wait for e39 experts to come in give them a few minutes.

[snapback]250525[/snapback]

A mechanic said and replaced the mass air flow sensor but the problem is back i think i got ripped off with that job.

[billB]

Originally posted by d3s3rt+Dec 14 2004, 11:38 PM--><div class='quotetop'>QUOTE(d3s3rt @ Dec 14 2004, 11:38 PM)</div><div class='quotemain'><!--QuoteBegin-Torque@Dec 14 2004, 04:29 PM
bad throttle cable ?

i guess we can wait for e39 experts to come in give them a few minutes.

[snapback]250525[/snapback]

A mechanic said and replaced the mass air flow sensor but the problem is back i think i got ripped off with that job.

[snapback]250542[/snapback]

[/b][/quote]

I think the answer should be hidden somewhere in you CHECK ENGINE light and a CODE or two will do. Is it turned on? If so what numbers/codes?

In addition to Torque's answer my GUESS will be your ICV Idle Control Valve: you may get away with cleaning it or a replacement. Either way you need a code.
good luck

[d3s3rt]

Originally posted by billB+Dec 14 2004, 04:47 PM--><div class='quotetop'>QUOTE(billB @ Dec 14 2004, 04:47 PM)</div><div class='quotemain'>

A mechanic said and replaced the mass air flow sensor but the problem is back i think i got ripped off with that job.

[snapback]250542[/snapback]

I think the answer should be hidden somewhere in you CHECK ENGINE light and a CODE or two will do. Is it turned on? If so what numbers/codes?

In addition to Torque's answer my GUESS will be your ICV Idle Control Valve: you may get away with cleaning it or a replacement. Either way you need a code.
good luck

[snapback]250579[/snapback]

[/b][/quote]
the check engine light is not on, could it be some kind of vacuum leak

[billB]

ok let us try this:
A. Your car is equipped with “Check Engine light” so how did your mechanic diagnosed/knew it was a bad MAF prior to replacement. Did he hook it up?
B. I expected you to get at least one CODE such as “idle control NOT plausible” or another one like “O2 sensor Control Limit” you’ll get it when engines run too lean=vacuum leak, or too rich.
C. No check engine light? When you turn the ignition key on, do you see the light ON before starting engine? Does it disappear after engine starts? What I am getting at is the possibility of burned out bulb or someone took out!! Strange things happen. Let us know

[d3s3rt]

hi i checked it out the check engine light does go on when i ture the key but goes out after the motor starts the mechanic hooked something up under the hood and at first he said it was a vacuum leak so when i left it with him he called back and said that he was wrong it was the MAF

[billB]

So the mechanic was wrong twice: in vacuum leak and MAF! To the vaccum leak, do you hear a hissing noise? something like wooosh when idling or when reving a bit?

[billB]

At this point and before quitting on you, the only thing comes to mind is a software update and/or the vanos unit- sometimes these two, don't give you a check engine light. A good mechanic with diagnostic tools will do; Good luck.
Anyone else?

[d3s3rt]

well i got it fixed 2 weeks ago and it was fine for 1 week, then one night i was driving hard and when i let off, the motor continued to rev at about 3000 rpm and went down slow to about 1500 but when i keep it in gear at a stop light and i let off the clutch slow the rpm goes right down and when i put it in neutral the rpms are fine until i hit the gas again.The day after that happened i popped the hood and played with a few things aroung the MAF and throttle body the car ran fine.

[d3s3rt]

Originally posted by billB@Dec 16 2004, 09:18 PM
At this point and before quitting on you, the only thing comes to mind is a software update and/or the vanos unit- sometimes these two, don't give you a check engine light. A good mechanic with diagnostic tools will do; Good luck.
Anyone else?

[snapback]252762[/snapback]

billB thanks for all you help

[///M Power]

MAF you alreayd took care of.
Clean your Idle control valve. If no luck try changign your O2 sensors.

[d3s3rt]

hi guys, last night just before I jumped on the hwy the problem came back.It was acting up the whole ride on the hwy and it was gone as soon as i got off the hwy I was on for about 15 minutes. I have noticed its been happening when it wet out is there anything that could be geting wet that could cause it. I havent got the chance to check out the idle control valve yet but ill check it soon just want to see if there is any thing else that could cause it like the wet weather.

[grtmoby]

clean the throttle valve gate as it is sticky. This is your issue.

[bob in houston]

for what it's worth...my '95 530 started to rev REAL high at a stop light some time ago, i had to kill the engine it was so high. it ended up being a cracked intake manifold boot. i too also replaced the MAF, to no avail. if the intakle is old it could be very britle and cracked, as mine was. good luck.