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m78

At startup, the engine stalls several times before continuing to run correctly. I can smell just the fainest odor of fuel, which leads me to believe the engine's getting too much fuel and therefore stalling. On warmer days, it seems to start much better.

At first I thought it was coolant sensor(s), so I changed both of them, and still it stalls at startup. Then I replaced AFM, oxygen sensor, and spark plugs. Still no improvement.

Could this be a vacuum leak? Could it be a valve cover gasket?

Fuel pressure regulator is likely going to be my next part replacement along with checking vacuum lines.

Any other suggestions?
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Lachssilber Metallic 203 1988 325i sedan with 200,xxx miles

Top Speed 220 km/h

(OO=00=OO)

bearing01 · Joined: 22 Jul 2005 Posts: 520 Location: San Diego

Sounds like you could also be experiencing a lean start, not a rich start. I say this because when the car is warm you don't have the problem. That or a leaky injector.

Next time it's cold, try bypassing the fuel pump for a few seconds before putting in the key and cranking. See if you got low residual fuel pressure. This could be from a bad FPR, leaky injector or bad check valve in the pump.

rj7hills · Joined: 29 Jan 2004 Posts: 573 Location: Rome, GA

Could also be a leaking fuel line effectively letting the lines empty when it sits for a few hours. Check for small cracks in the lines. If it looks like the hoses have been recently replaced, check for the short hoses under the intake. Also make sure the fuel lines are made foro fuel injected systems. The hoses for carbureted cars are rated for a different pressure an it will make a difference.

m78 · Posted: Sat Mar 17, 2007 10:07 am Post subject:

That's not a bad thought, although I don't smell fuel at all, until I start the ignition. If it was a leaking fuel hose, I would think there would be a faint smell of fuel more often than there is.

I've now replaced the fuel pressure regulator, and results are undetermined, but it appears initially that it did not solve the problem.

Now I'm thinking, there must be a vacuum leak.

How many vacuum lines are there? Are there some that would be more obvious than others? Could there be a vacuum leak at the valve cover? I'm planning on replacing the valve cover gasket anyway, could there be a vacuum leak there that is causing this hard starting problem?
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Lachssilber Metallic 203 1988 325i sedan with 200,xxx miles

Top Speed 220 km/h

(OO=00=OO)

m78 · Posted: Sun Mar 18, 2007 4:37 pm Post subject:

I've now replaced the valve cover gasket, with no improvement on hard starting problem.

it happens generally when it's cold.

Am planning on pursuing the wiring for the coolant sensors and/or the fuel injectors.

anyone else have any suggestions.
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Lachssilber Metallic 203 1988 325i sedan with 200,xxx miles

Top Speed 220 km/h

(OO=00=OO)

AussieAl · Posted: Sun Mar 25, 2007 8:36 am Post subject:

M78, Invest in a fuel pressure tester..it will save you an enormous amount of time & $$ in uneccessary replacment parts. mine (84 323i Aust version) sufferred from the same symptoms & it turned out to be the check valve in the fuel pump. The logic behind this defeats me as the valve holds residual pressure so you would think when starting that there is no fuel in the rail & pressure builds as you crank. Maybe the mix is too lean initially & thats why you smell petrol. i think bearing01 is on the right track but you'll need a pressure tester to check the residual pressure. i dont think its a vacuum leak as it would manifest itself all the time not ust cold starts.

m78 · Posted: Sun Mar 25, 2007 8:49 am Post subject:

Interesting.

Yeah the pressure tester is not a bad idea. The cold start up is the thing that confuses me. I did invest in some techron injector cleaner this past week and it seems a bit better. I also replaced the 2 vacuum hoses at the idle control valve and replaced the main relay and that seems to have made a positive improvement.

Although, it's been fairly warm days, so it's hard to tell.

Now I'm chasing a central locking gremlin argghhh!!!!

At least she's still getting me back and forth to work everyday through all this. But these recent issues certainly illustrates why most men refer to their cars as "she" LOL.
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Lachssilber Metallic 203 1988 325i sedan with 200,xxx miles

Top Speed 220 km/h

(OO=00=OO)

AussieAl · Posted: Sun Mar 25, 2007 9:27 am Post subject:

M78, Glad to hear you've had some improvement. The australian versions arent motronic - still got a "normal distributor" & no idle control valve - so fault finding is a little easier as the fuel/ignition are separate systems. the cold start problem may have been a minor vacuum leak that manages to seal when warm. Thats not an uncommon scenario for coolant leaks, they can drip when cold but seal when warm ( and pressurised...figure that one out for logic!!). Hope the problems fixed but I'd still be leaning on the fuel side of things. Does it take long cranking when cold to start before stalling or the same as when warm? mine progressively worsened - longer & longer cold cranking - before it would start, which made me think it was the check valve. Good Luck

m78 · Posted: Sun Mar 25, 2007 10:36 am Post subject:

Actually it kicks right up whether it's warm or cold, but then suddenly dies when cold. 3-4 more starts and dies before it is able to idle on it's own.
_________________
Lachssilber Metallic 203 1988 325i sedan with 200,xxx miles

Top Speed 220 km/h

(OO=00=OO)

kyshadetreebmw · Joined: 16 Apr 2003 Posts: 849 Location: Berea, Kentucky

I just cured a stalling, while at cold idle, problem on a 318i by replacing the fuel filter! And I had thought it was a rich mixture problem but I guess it was a not enough volume problem=lean problem as suggested above.

m78 · Posted: Mon Mar 26, 2007 9:40 am Post subject:

Yeah, I've got that in mind too.

I bought a new fuel filter a few weeks ago and plan on changing that too.

Also, I am going to replace the idle control valve.

It was a bit cool this morning and although she started right up, with no problem, the green check engine light flickered while driving down the road immediately after startup. It generally happens when I push in the clutch to come to a stop shortly after taking off from starting up cold.
_________________
Lachssilber Metallic 203 1988 325i sedan with 200,xxx miles

Top Speed 220 km/h

(OO=00=OO)

kyshadetreebmw · Joined: 16 Apr 2003 Posts: 849 Location: Berea, Kentucky

Hey, have you resolved this?

m78 · Posted: Sun Apr 08, 2007 11:21 am Post subject:

Thanks for asking and no I haven't.

I've been chasing a couple of other gremlins. I haven't had time to replace the fuel filter. But at least she's running after warmup.

She still starts hard when it's cool though.

The central locking problem is still on my plate as well as a a/c issue. Which hopefully will get cured at the shop this week.

I truly like this car, but she can be so tempermental sometimes.
_________________
Lachssilber Metallic 203 1988 325i sedan with 200,xxx miles

Top Speed 220 km/h

(OO=00=OO)

mik_meister_99 · Joined: 24 Mar 2004 Posts: 121 Location: North TX

For a few years I had battled fuel smells and hard starting when HOT (I know this is contrary to your starting when cold condition), however I would question your injectors here. After 200k, I believe your problem is here. Have you ever replaced them? I replaced mine a month ago, and the car is running better than it ever has (even have a slight improvement in mpg). When I pulled mine, the pintels were broken and the injectors overall were very worn looking. I only had 148k on them, but like I said - the car is so smooth now, and no fuel smells at all, so I know (and suspected) I had a leaking injector. I got mine at Five O. Money well spent if your intending to continue driving it.
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1988 325is 5-speed (Molly)
172k
You know you've got an e30 when you turn your radio up to mask valve clatter.

m78 · Posted: Sun Apr 08, 2007 5:09 pm Post subject:

I agree. That's probably the next step.

I changed the fuel filter today, and it appears it's not made any difference.

I'll know better tomorrow morning when it's colder, but preliminary indications are it's looking more likely an injector problem.

Didn't want to spend that kind of money, especially with the a/c bill coming up, but if that's what it is, then I guess I'll have to take the plunge.

The good news is my central locking problem is resolved Hooray!!!

Did you upgrade your injectors?

How much did all six cost you?
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Lachssilber Metallic 203 1988 325i sedan with 200,xxx miles

Top Speed 220 km/h

(OO=00=OO)