New engine revs high when starting for 1 sec

[kaineb]

Put in a newer m52 in my 95, 325i. Full obd1. When i first start the car the engine revs up high for just a second then comes back to normal and is ok. I do see a stutter here and there but i just got the motor running and not sure if this is to be expected while it is learning. I did clean the IAC as it was pretty dirty in there. Again i am just getting it running. Engine had sat for some time.

[travis325i]

My car does the same when it's really cold or it could be a vacuum leak idk

[kaineb]

These cars can be a pain. It better be worth it when i am done.

[travis325i]

Dude it's always worth it once it's done I've been through alot with my e36 but it always still puts a smile on my face when I drive it. E36 FTW!!!

[kaineb]

You want to know something funny, i bought this car from a dealer in fair mechanical condition for a reasonable price. Body/interior are beautiful.

I drove it from the dealer home and that was it, up on jack stands and torn apart. Never have driven it as it has undergone a new engine and a few grand in parts effectively replacing, repairing or servicing every part of the drive train, suspension and many other various parts that support it. also have done lots of work to little issues in the interior as well, sunroof, etc. It nickle and dimes you to death. But! in the end i will have a mostly rebuilt car that i don't have to worry about.

Also an OBDI M52, eventually with mods. It will make about as much hp as an m3 with less torque. Still will be peppy. And its more fun learning and doing this stuff yourself anyway.


Now back to my original question.... Anyone had this issue?

[jijacob]

Can you post a vid so we can see exactly what you're talking about? It is probably a side effect of the OBDI conversion

[kaineb]

Not sure a video is needed to explain. You start it, the idle goes up high right away for about 1 second and then it comes down and stays where it should be. But if one is needed i can do that when i get her running again. Working on the cooling system.

Like the mods you have done with your 325i. That is what mine is. Well technically now its a 328i

[slocar]

Define high. How many revs?

[kaineb]

I would say 3000-4000rpm. But again its just for a sec and levels out. Its that very first second or two of startup. Quickly comes down to normal idle. My previous engine did not do this and its almost all the same stuff back on this. But possibly is it because it is a OBDI M52 and the computer needs to learn it?

- Idle control is from the new engine but same model as old (I did fully clean it)
- Valve cover is from new but have a good seal on it vacuum wise.

[E36 grenade]

unhook your batt for ten minutes its the adaptations just needs to re learn a faster way is to disconect and reconnect then go drive the piss outta it

[kaineb]

Battery had been disconnected for a while before i dropped the engine in and fired her up. Cant drive it yet. I suppose any bugs maybe i should get her together and out on the road first then see what happens. Soon.

Hey Grenade what headlights are those? Look nice.

[PBergeron]

Don't all cars do this at start up?

[Barryo2002]

Originally Posted by PBergeron

Don't all cars do this at start up?

Mine does and its strictly OEM beneath the bonnet. Strange thing is that the odd time it accelerates even when the car is hot. At traffic lights or when i park. Its a 5 speed manual 318is. It goes from idle 900RPM to about 1500-1800 RPM.

Any ideas on that?

[randomy]

Mine does not do this. But it sounds like a sensor (MAF, ICV, temp,) may be bad, that is putting your engine system in open-loop, used for cold-starts, at every start.

[E36 grenade]

Thanks there depos w ddm angel eyes also on newer bmws leavin the key on for 5 to 10 minutes clears the adapts not sure on the e 36. Worth a try

[MikeVance]

mine does the same. maybe not THAT high.

i also have vacuum leaks so look at that.

[kaineb]

Grenade,

Do you think angel eyes are a younger mans toy? Kind of like having neons under the car? I like them but at 36 i wonder if i would look like a fool. Not sure if they are seen the same. Either way the lights are something i think i am going to get. Probably without angel eyes.


Back to the original problem, please remember my M50 that i just removed did not do this with all of the same stuff on it. And yes i had removed the battery for long periods od time in between engines.

[shreker]

its probably your icv...people clean them out but that doesnt always fix the problem!!sometimes you have to say fuck it!!!and change it out!!

[Calimins]

+1 on icv

[Barryo2002]

ICV= Indigenous Community Volunteers ??? Islamic Council of Victoria ?????

Lol, for all of you guys who just got outta bed and had to google ICV, its Idle control valve.