Author Topic: New Car: BIG cold start problems (Read 27298 times)

fiftytakedowns · « **on:** February 10, 2009, 12:32:39 AM »

Recently Got a 1991 318is not to long ago.

The car runs well, and drives well ONLY when FULLY warmed up.

PO said the ICV could be bad, but I took it to a shop, and they said all need to do is clean the ICV (regarding the ICV problem). So I cleaned it iwth some brake clean shook it up and repeated.

Symptoms.

Car starts fine, and idles a little rough, with some minor surging, not noticable by RPM, only by ear.
If I put it in gear and start to drive before the heat needle is smack dab in the middle. It will rev up to about 2.5, and Bog down with my foot is on the gas. If I take my foot up, and try again it will rev up a bit more, then bog down again. sometimes it will bog down, and get spurts in and out of normal driving conditions.

Goes away once warm.

I also found out that the PO had deleted the Heater plate, not sure what else he has done,
but he said it could use a dinan chip, and yet the car will willfully rev to about 7000. seems like it does not have a limiter, or there may be a chip in the car already.

could this affect the car when it is warm with milage etc...?

Clean air filter P.s.

2002 guy that found an E30 as a daily
I dont know much about e30's but I have searched a bunch.

Thanks

haledj · « **Reply #1 on:** February 10, 2009, 12:41:38 AM »

Sounds like a coolant temperature sensor

tjts1 · « **Reply #2 on:** February 10, 2009, 01:18:15 AM »

I'm guessing massive vacuum leaks underneath your intake manifold from the previous owner's bodged attempt to remove the TB heater plate. See the link in my signature for more details. These cars have all sorts of issues with cold weather so you're definitely not alone.

fiftytakedowns · « **Reply #3 on:** February 10, 2009, 10:39:22 AM »

To check for vacuum leaks, dont I get a propane bottle, and if it changes the idle i am in the right spot?

Im compiling a to do, and possibility list of problems.

In addition, I noticed on the (messunder the intake thread) that my ICV is upside down. The Big bulky part with the wire boot is on top, while the connectors to the hoses are on the bottom. Not sure if it makes a difference though.

tjts1 · « **Reply #4 on:** February 10, 2009, 11:16:08 AM »

There is an arrow on the ICV that should be pointing toward the manifold. For the vacuum leaks, don't worry about using a propane torch. I would just take a very close look with a flashlight to check for cracks, loose hoses etc. Pretty much every M42 has this problem. Its a matter of age.

fiftytakedowns · « **Reply #5 on:** February 10, 2009, 02:37:29 PM »

The arrow is pointing towards the manifold, but it is upside-down

fiftytakedowns · « **Reply #6 on:** February 15, 2009, 06:37:23 PM »

I took a look at the engine bay looking for anything that could be corroded or any leaks that could occur. There was definitley no vacuum leaks that were obviously apparent. The hoses were all replaced by the PO.

I am stuck upon what could be the problem. I have to wait about 10 minutes to drive the car, or else it will agressively bog down at 1500 RPM. Sometimes sputter.

xwill112x · « **Reply #7 on:** February 15, 2009, 10:20:53 PM »

02 sensor.

AcSchnitzer318is · « **Reply #8 on:** February 16, 2009, 12:05:58 PM »

Check the "did we ever figure out the warm start issue" thread. If it applies to you great, if not, oh well it only takes 5 minutes to check and see if your wire is plugged in or not. Remember the wire should be disconnected for all US e30s with cats. Mine was plugged in after engine rebuild and did what you described for over a year until that thread.

xwill112x · « **Reply #9 on:** February 16, 2009, 03:15:17 PM »

Quote from: AcSchnitzer318is;66629

Check the "did we ever figure out the warm start issue" thread. If it applies to you great, if not, oh well it only takes 5 minutes to check and see if your wire is plugged in or not. Remember the wire should be disconnected for all US e30s with cats. Mine was plugged in after engine rebuild and did what you described for over a year until that thread.

+1

i didnt think of that.

fiftytakedowns · « **Reply #10 on:** February 20, 2009, 03:09:27 PM »

consdering the cat is bad, and rattling under the car, (supposedly replaced) AHA! it might be it,, Ill check when I make it back home

max123 · « **Reply #11 on:** February 22, 2009, 10:32:52 AM »

Mine had a similar problem. When the engine speed/idle starts going crazy do you get a check engine light? If so, best bet would be to take it down to your friendly neighbourhood mechanic and get them to scan it (even if the light goes out the error is saved - if you search this forum there is a low tech way to get this info involving turning the key on and off and pressing the gas - i'm not joking - search it).

On a related note - I had virtually the same problem, turned out to me the mass air-flow meter - sadly, $800 new from BMW - but happily $40 on craigslist. (Also, I've noticed that on this forum any and all idling problems are always traced back to the ICV or vacuum hoses. This might be right 90% of the time, but after I replaced my air flow sensor I noticed that engine response was much better and cold startup was dramatically improved)

Cheers,

max123 · « **Reply #12 on:** February 22, 2009, 10:34:30 AM »

One other note - I used an air flow meter from a 1992 e36 m42 - different part number but is still works (possibly even better than stock??). search junkyards.

fiftytakedowns · « **Reply #13 on:** February 22, 2009, 06:52:06 PM »

My check engine light only goes on sometimes, right after I turn on the motor, then it goes away after a couple of minutes. never goes on when I am driving though.

I will try the engine codes thing. see what I can get.

I might have an easier way to describe the problem also.

as the car warms up the number(Rev) for which it chokes out, and the motor decelerates increases at the same rate as the needle moves along the temp gauges. For example chokes out at 1500 RPM completely cold and then 2000RPm at about 1/4 distance, etc... Also chokes out or bogs, when I am just revving up the motor.

There is also a bumpy,surging Idle until the motor is cold.

Thanks

fiftytakedowns · « **Reply #14 on:** February 23, 2009, 03:27:10 PM »

how do I check if the AFM is faulty, I would like to order some parts, and make a junkyard parts list for tune up and to fix this problem.
so bump