Bimmerfest - BMW Forums

Bimmerfest - BMW Forums (
-   E36 (1991 - 1999) (
-   -   318is dies while idling/driving and bucks (

Hellrot_318is 11-29-2011 09:40 PM

318is dies while idling/driving and bucks
So I replaced the engine in my 97 318is with a stock M44 engine (1.9) about 3 months ago, and this problem just started happening.

The other day I was on my home from work going about 35MPH and the car started bucking. I pulled into the parking lot, shut it off, and started it back up. I drove around the parking lot and it was bucking again. I checked my battery and my positive cable is connected via a stereo terminal and it was a bit loose. I tightened it back up and disconnected the negative so the ECU can "recalibrate" hoping that was it.

The car still did it in the parking lot after that, but I gambled and drove home. It was totally fine. I thought it was a hiccup and then I remembered I usually fill it with 89 (which is what the sticker recommends), but the last time I put in a half a tank of 87. That gas was just about burned off and I filled it halfway with premium fuel.

The fuel filter is probably 3 years old (and over a year and a half the car sat while I put in the engine, long time I know). I replaced it today and started it up, and let it idle for a bit. It was totally fine, but then it just randomly died about 5-10 minutes later. It always starts back up without any problem though.

I took it for a spin around the block and it seemed fine, but then it started to buck and the throttle was unresponsive, and then it kicked back in and drove normal again.

When it idles or stalls out, it always starts back up fine.

I'm thinking:

-My o2 sensor is damaged slightly ( I think I had it still connected while removing the exhaust by accident, but it's been working for 3 months) Maybe it just gave out?
-Bad fuel pump? Do bad fuel pumps give "blips" or when they go bad, they are done for?
-MAF sensor?

Can someone point me in the right direction? Money is very tight right now and I cant afford to be throwing parts on it hoping to fix the problem.

Note: While revving it in neutral, idle to about 3K RPMS seems to be a bit rough. It's not a smooth rev.


Archetype 11-29-2011 10:39 PM

Sounds like a fuel pump issue. It ll get worse and then go out completely. I could be wrong, but sounds like thats it.

hornhospital 11-29-2011 11:08 PM

Agreed. Fuel pump and/or fuel pump regulator. Test your fuel pressure at the injector rail.

Hellrot_318is 11-30-2011 03:21 PM

Cool. I see if I can pick up a fuel pump. It has pumped 170K miles worth of gas. Anyone else experience this problem before?

tchavera 12-01-2011 06:28 PM

before you order parts.. do you have a check engine light? a MAF sensor will normally give a light. it is possible for the issue to be a MAF sensor. test your fuel pump by turning the key to the on position while having someone get down by the gas tank and listen for it to turn over

Hellrot_318is 12-02-2011 12:37 AM

There is no CEL. I guess I didn't listen for the fuel pump energizing, but the car does start every time, and it does run, but like i say will die out randomly.

Hellrot_318is 12-16-2011 03:58 PM

I replaced the fuel pump and let it idle for a while, and it sounded like it fixed it. But 5 minutes later the car died while idling, and stumbled upon startup. Once it starts, I "clear it up" by giving it some gas and it seems fine. But it will die again, and when I took it around the block, it jerked again, but then clears up.

Any other troubleshooting steps I can take? I know my o2 sensors have not been changed ever! (173K miles), and the front o2 sensor is slightly damaged. I'm going to replace it to see if that works as it probably needs to be replaced anyway, but can anyone think of anything else?

luckeedog 12-17-2011 10:48 AM

Just keep throwing parts at it you will get there eventually. If you had spent a portion of the money you spent on a fuel pump to buy a fuel pressure gauge to properly diag the problem you would be ahead of the game.

Hellrot_318is 12-17-2011 10:58 AM

Well the fuel pump wasn't too expensive, as I bought it used on ebay ($35). I'm going to rent a fuel pressure tester kit from autozone and check out the o2, MAF, check vacuum lines for a leak, possibly a smoke test and go from there.

kmorgan_260 11-19-2012 03:22 AM

OP, did you sort out your problem? What finally fixed it for you?

Hellrot_318is 11-19-2012 04:10 AM

Yes I did. It finally threw a code when it was sputtering and about to die. Yours might not throw a code, because mine did it a bunch of times with no code. Camshaft position sensor. I replaced it with an OEM one (about $110) and it worked perfect after that.

I also have an extra non-oem one that I put a bid on ebay for through my friends account. I forgot about it and bought the OEM one, and he ended up buying it. I still have it, and I'll sell it to you for $30 shipped. He bought it for $60 from a reputable import part specialist. Email me if you want it.

As always, OEM is better than generic, but hey it might be worth a shot for $30.


All times are GMT -7. The time now is 11:25 AM.

Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
© 2001-2015 performanceIX, Inc. All Rights Reserved .: guidelines .:. privacy .:. terms