3-Series (E21, E30)Chat relating to the BMW 3-Series from 1975-1983 and 1984-1991 line. Specific models: BMW 315, BMW 316, BMW 318, BMW 318i, BMW 320/4, BMW 320i, BMW 320/6, BMW 323i, BMW 320i. E30 Family models include: BMW 325e, BMW 325i, BMW 325is, BMW 325ix.
Before anyone flames me for asking that age old question, Why won't my E30 start" please recognise that I DID read all and every post I could find online ! I tried everything, I have the Bentley Guide, I have the Haynes manual and I have a pretty full toolkit, the only thing I don't have is a working 1985 325e !
OK That's out of the way.
I got a 1985 325e recently that was a fully running car and just needed some minor things fixed to get it on the road. When I say fully running, I drove it to my house and regularly moved it around ont he driveway while I waited for parts.
The first fix was the Windshield Wiper linkage and replacement of the blower motor. This was completed in an afternoon and the car still worked, i.e. turned over, fired and moved.
Second fix was a new alternator as there was no voltage from the old one. In replacing this I had to take off the Air Filter, diconnecting the MAF and something else connected to the top of the Air Filter. Replacing everything the way I found it, unfortunately since then the car has not fired !
I have beautiful spark, full fuel delivery and even have replaced the fuel with brand new fuel draining the tank by bypassing the relay to make the fuel pump run full time (as per Bentley).
However, the car will not fire at all, I can turn it over till the battery is dead (and then fully recharge) but nothing.
Took the plugs out, they were wet, dried them, left them out for a few hours after turning the car over with no plugs to clear the cylinders, nothing.
I'm at a bit of a loss at this stage and I'm REALLY hoping someone here can help.
Welcome to the Werkz. Hopefully someone here can help
So confirming that you have a solid crank from the starter motor, a spark on all xylinders and each injector is firing? You should get a strong smell of unburnt fuel from the exhaust but still no sign of ignition? Something doesn't add up, unless the crank position sensor is way out, or the injectors aren't firing properly. Is it possible that the MAF as collected some serious crud in the process? Try disconnecting the MAF and crank it over, see if there are any changes to the symptoms.
Confirmed, have spark, solid crank and fuel going through the rail as tested with the cold start injector, fuel entering the rail and fuel leaving the Fuel Pressure Regulator !
Last night about 10pm after posting I even called a friend to come an turn it over as I had a brain fart and wanted to make sure the timing belt was moving ! No problems there either, thank God I have an understanding Gear Head for a friend
The MAF is probably crudded up as there has been fuel coming UP through the intake it got flooded so bad ! I'll disconnect and try tonight.
Just another piece of info I forgot, even putting Quick Start (Ether) in the air intake on the side of the plenum while cranking gets not hint of ignition.
For the crank position sensor, I tested the resistance and get the proper spec from Bentley. I also thought if the sensor was gone, I wouldn't get spark at all, is that correct ?
To help dry out the cylinders of excess fuel, pull the spark plugs out as well as the fuel pump fuse. Crank it over to push some air through the system and hopefully expell the unburnt fuel that it sounds like you have accumulated in the system. Make sure that there is no source of spark when you are doing this. Are the injectors possibly sitting open constantly, or can you hear them firing individually?
Did these steps last night and made sure there was no fuel in the cylinders. Was a bit more risk taking and put a torch to the plug hole Yup all the fuel was gone after THAT !
I was humming and hawing about the possibility of reduced fuel pressure not atomizing through the injectors and in the absence of a fuel pressure gauge, clamped the return pipe off the pressure regulator to see if it would even fire after clearing out the cylinders.
I am utterly at a loss. To the best of my reading ability, if there is spark at the plugs and fuel is being pumped on turn over then the crank sensor et al are functioning ! So the engine has spark, fuel, air (took off the hose from the MAF to the intake) and compression. Am I missing something basic ? What's left !
Just decided to go through the triangle again, fuel, spark and air.
Pressure on the fuel rail, cold start injector working, have to get a noid set tomorrow but since it's flooding the fuel is getting there in some part anyway
Tested each spark plug individually, nice white/blue spark on each one
Hmm..... had been assuming air as I had the MAF disconnected from the plenum so theory would have that the engine can suck straight in through the throttle body.
Well, unless a 2.7 L engine can ignite fuel on a puff of air, there's probably something wrong here ! I have 4.2 L '95 Range Rover and on ignition if you put your hand over the intake like that you run the risk of losing it at the wrist ! Not on this test.
Nothing, I've taken off the hose to the air intake on the throttle body which also leaves the idle adjustment valve hose open.
Spraying quickstart in either of these doesn't do a thing !
I'm starting to wonder if my cam timing is off. Thought through it again and even out of sync I would get good compression, but the spark and compression would be off. However, I though this was an interference engine, so if it was off, I'm sure I would've HEARD it by now
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