engine turn but would not crank

[Pharaon]

hi! my BMW 318i 1997 would not start the engine is turning but would not crank, I just had a new ignition put on it worked for few day then the starting problem occur could you please advice on what to do.

regard

Pharaon

[Manolito]

What you need to do is collect more information.

Most likely, either the spark plugs are not firing for some reason, or no fuel is getting into the engine. We have to narrow it down to one of those two problems before we can proceed.

When you say that you got a new ignition put on it, what parts exactly were replaced? Did someone confirm a lack of spark, hence the new ignition? If so, then I would continue down that path, looking for the problem beyond the parts that they replaced. For example, the crank position sensor can fail resulting in lack of spark, but that might not have been replaced.

[baymvay]

I have a 1985 BMW 318i, with almost 149,000 miles on it. I purchased this vehicle in non-running condition. In order to get it running again, I replaced the fuel tank, both fuel pumps, and fuel pump relay. The fuel injectors were cleaned and overhauled. The compression was about 150 psi on all of the cylinders. The car started and ran…until the other day. I started the car up on my driveway, and I let it warm up…soon thereafter, the catalytic converter was glowing red hot, and smoke was coming out from under the car. I shut the car off and let it cool down.

In the next few days, I verified that there is a spark at the ignition coil. I pulled all of the plugs and there was black carbon on them. I made sure that the fuel pumps were working, but I did not check the pressure. I loosened up the exhaust pipe before the catalytic converter in order to temporarily relieve excessive back pressure if the catalytic converter was clogged.

I checked all of the fuses and relays, and they were all good. Does this vehicle have a crankshaft position sensor? If so, where the heck is it? Could that be the problem? I cannot seem to get this car to start. What else could it be?

I'd appreciate your input.

Sincerely,

Jason

[bostogrun]

The reason your cat was red hot was because raw fuel was being dumped in it and igniting inside it.

Yes it does have crank sensor but I don't this is your problem. You said your injectors were cleaned and overhauled? How were they overhauled? I never heard of that.

[baymvay]

well, I took them out of the car, disassembled them (removed the seals, etc) and soaked them (in Chemtool or Seafoam)...got them squeaky clean...I connected voltage to them and listened for the 'click' sound...I installed new seals and cap...and installed them in the vehicle...engine started right up (after sitting for about two years before I bought it). Basically, I went thru the entire fuel system, replaced what it needed, and cleaned the rest up. I also replaced the fuel filter and some fuel lines. I made sure that everything was snug, tight, and secure. SOmeone suggested to me that the injectors may be stuck. I think that I will pull the injectors and check them out.