Author Topic: 318i 1997 won't start (Read 5816 times)

tunnie09 · « **on:** June 15, 2009, 09:56:54 AM »

Hi I'm a newbie, and I'm posting on behalf of my brother in law.

He recently bought a 1997 318i, at first it was running, idle was fine but really lacked power. I suggested changing the fuel filter, which he had done.

Now the car won't start. Right I'll go through what's been done so far:
1. Fuel Filter has been replaced
2. Coil, crank sensor, cam sensor has been changed for 2nd hand units
3, I have checked that we are getting a spark to each plug.

Yesterday I took out each plug and they where wet, I heated them under the grill then put them back in. The car did start with the throttle fully open, however when the throttle is released the engine dies. then just failed to start again.

I'm sort of at a deadend now as I don't have much experience with BMW's (Ex Rover Mechaninc)

Any advice will be appreciated. Thank you.

DesktopDave · « **Reply #1 on:** June 15, 2009, 10:45:18 AM »

I'd check that throttle position sensor. It could be that, or the DME is going into 'flood clear' mode. I don't have the resistance values off the TPS, but there's a copy of the e36 manual here that might help you.

The Crank pos sensor causes a lot of trouble too...you might want to double-check the resistance on that. I think it's around 600 ohms between pins 1 & 2. It'll spark but refuse to turn on the fuel pump if that sensor is bad.

Welcome to the board...sorry it's for a no-start.

AdamG · « **Reply #2 on:** June 23, 2009, 07:46:15 PM »

I'm also having trouble with my car, a 1997 318i with M44 engine. I was driving today on the highway when it broke down. For several miles I heard a tapping noise that seemed to be coming from the vent, but eventually I realized it was getting worse, and when I accellerated it was tapping and when I wasn't on the accellerator it wasn't tapping. I pulled to the shoulder and the engine stopped and smoke came from the engine. The car wouldn't start again. The oil level is good, there are no oil leaks, no holes in the engine block, and nothing looks wrong, it just won't start. The battery still has power and the starter will spin, the engine just won't turn over. After cranking the starter for a few seconds an odd odor apperars, sometimes it smells like gas. I'll check these suggestions for sure. Any other suggestions? Thanks!

DesktopDave · « **Reply #3 on:** June 23, 2009, 09:32:01 PM »

Stop turning your engine over. I have some bad news. I'd guess your chain tensioner failed, the cam gears skipped, and the valves were bent by the pistons. If I'm right you'll have to have your cylinder head removed and refurbished. A machine shop would be a good idea.

You can help us diagnose the trouble by removing the cylinder head cover and snapping a few pictures for us. You could also do a compression test...

Sorry to give you such bad news...hopefully I'm wrong and it's just a bad crank position sensor or something else trivial.

bullmand · « **Reply #4 on:** June 24, 2009, 09:37:43 AM »

Desktop Dave,
Thanks for the suggestion. I think AdamG's description is a little confusing. I picked him up from the side of the highway yesterday and we did a little unsuccessful troubleshooting. The engine does actually turn over, it just won't start. The starter sounds normal and the engine is clearly turning over without making any unusual noises, it's just not starting. We checked the spark and that seems good, but it seems like it might not be getting fuel. There's a hint of a smell of gas coming from the fuel rail area when you try to start it but it's pretty faint and there's no visible liquid. The check engine light did come on at some point during the pulling off the highway portion of this and we're trying to get a hold of a code reader now to see if that can point us in the right direction. We're going to follow the troubleshooting guide in the Bentley manual, but the tapping and the smoke are confusing and concerning. We'll keep you posted and if anyone has any more ideas we'd love to hear them.

DesktopDave · « **Reply #5 on:** June 24, 2009, 10:34:51 AM »

Sounds like your fuel pump isn't working. To test:

I'd try to get the codes read. Do you see the check engine light at all? If so, the ECU/DME is likely OK. Early e36s had trouble with the ECU flooding (especially after heavy rain or a pressure car wash) in the plenum. Just for kicks, check the drain tube coming out of the firewall on the passenger's side.

1. Turn the car power on (don't start it) and jump the fuel pump relay socket with a short wire from terminals 30 to 87. If you can hear the pump working, then you can eliminate it as a cause.

2. Test the fuel pump and main relays while you're at it...connect terminals 85 & 86 to a car battery and listen for the click. That'll eliminate the relays as a problem.

3. Test the crank position sensor for proper resistance. Pull the connector and ohm out pins 1 & 2. Should be about 700 ohms. If that sensor is too dirty or resistance is worong, the ECU/DME won't detect the engine spinning and it will not start the fuel pump. Oddly, it won't set a code either.

AdamG · « **Reply #6 on:** June 26, 2009, 11:08:05 AM »

DesktopDave,

Thanks for the information. We tested all three above. Numbers 1 & 2 were fine, but we found that the crank position sensor seemed to have low resistance. We replaced it. Here is the latest, I posted it to 318ti.org: http://www.318ti.org/forum/showthread.php?t=27191

DesktopDave · « **Reply #7 on:** June 26, 2009, 11:12:57 AM »

Damn, sorry to hear about the gasket. At least the bottom end is intact and no bent valves. Could have been far worse. If you do the swap, sell the block to us here. We always seem to need 'low-mileage' M42's!

I always thought those ti's were great cars. Lighter than the sedans with the same rear axle as our beloved e30's! I've seen some M50/M52/S52 swaps...it'd be a blast to drive, that's for sure.