Sounds like it is not getting any gas. I know I have a good fuel pump, fuel filter, spark plugs and the such. Started and drove just fine last night, no problems at all. Went to start it this morning, less than 10 hours after it having driven it last night, and no start. Checked all the spark plugs and they are all fine (replaced them a couple months ago anyways). Every few time I try starting it it almost starts (spedo and cluster all jump to life like on a normal start) but it never will get quite started. I'm thinking it might be the Fuel Presure Regulator, but I'm not sure. What else should I check? This is my daily/only car so I need it running bad.
-
sigpic -
Re: HELP!!! Car Wont Start
It kind of sounds like you are stabbing in the dark on the FPR diagnoses. I would recommend cranking it, and immediatly removing a spark plug. If it is oily/wet looking, you have fuel. IF that is the case, have a friend crank the engine while you hold a spark plug with the electrode against ground, while it is plugges into the spark plug wire. You should see it sparking.Originally posted by DarkWing6
that will tell you if you have spark and fuel. You didn't mess with timing, so we will assume it is fine.
Even with your fuel pressure way off, it should still be able to idle. well I think so anyway.
-
definetly check for spark. You had this problem once before, maybe they missed something? I know you had your injection harness replaced (told you that TB leak caused bad problems!). your poor car :(Comment
-
I'm gonna check the spark as soon as my g/f gets off work so she can turn the key. Swapped the FPR and that wasn't it. And I fixed that leak the day after I got my car back from the shop. Looked at the gasket today and looks good as new. I was all excited cause I finally stiffend up my KONIs last night after breaking them in and now this!!!!!Originally posted by nando
If I have no spark where do I start? If I do have spark where do I start?sigpicComment
-
If you don't have spark, but your engine is cranking, you should check to see that you are getting 12v+ and ground at the coil first... then check the coil. It will tell you in your bentley manual how to do it. You get the resistance value over the coil windings, and check them and compare it to the value in the bentley manual.
Another easy part to eliminate is the spark plug wires. Just set your multi-meter to resistance (ohms), and check every speark plug wire, with one electrode at each end. they should all the the same... and it is normal for them to have resistance.
If you do get spark, and you have fuel... We will assume they are not happening at the right time. You can check timing on a non running engine by turning it by hand while the ignition is in the on position. you hold a spark plug like you normally would for testing, and when the distributor sparks the plug, you should be close to top-dead-center on the corresponding cylinder. On a low compression engine like an M20, if it is even close, it should be able to run. *NOTE- I did this on a 1981 toyota... I don't know if the BMW distributor and coil can spark without the engine running.
One other thing you can do is a leakdown test. I suppose a compression test would help also. You can have the right ammount of fuel, and be sparking at the right time, but if you have no compression, you won't fire. When you proporly do a leakdown test, you eliminate any possiblity of that being the cause.Comment
-
I'm just thinking, would all this happen overnight? It ran like a champ less than 10 hours before. No problems whatsoever. Could something have just bounced loose since I had just stiffened my suspension that night?sigpicComment
-
OK, so I have spark. I saw it and felt it. Could this be bad gas? I always put either Chevron or Shell Premium in it but could bad gas even cause this? I fiddle around with a few more things tomorrow, but for now it is time to sleep. Anyone that is willing to recieve phone calls to offer me help tomorrow feel free to PM you # to me. Otherwise please continue to check R3V throughout the day. I am suppose to be moving on Sunday, but my car needs to come along.sigpicComment
-
I doubt it was bad gas. BAd gas mixed with your good gas, and you usually won't even know unless you are forced induction/high compression.Originally posted by DarkWing6
I am thinking it is more likely you had some wires barely hanging on someplace and you lost a ground. Did you happen to pull a plug after cranking and check for fuel? The plug will be wet.Comment
-
Just checked and the plug was not wet at all.
EDIT: Just double checked the fuel pump and it is working.sigpicComment
-
How do you know the fuel pump is working?Originally posted by DarkWing6
The easy way to test with no tools is just pull the fuel line. not the one coming off of the regulator... the one that goes into the fuel rail. IT should spray out some residual pressure. wear safety goggles.
Next we weill check to see if you have any injector pulse.Comment
-
Originally posted by E30SRPower
I know it is working cause I can hear it and I replaced it about 3 months ago. But just to check again where is the one that goes into the fuel rail? exlpain more. kinda a newbie at fixin cars, but i'm catchin on quick.sigpicComment
-
I sold my m20 a month ago... So I can't tell you.
3 fuel lines come come up the firewall right inside the drivers side frame/uinibody rail. You will trace one to a vent or a charcoal can, and the other two will go to the fuel rail. The fuel rail is on the edge of the valve cover running lengthwise along it. It is on the passenger side of the valve cover I believe. There will be metal tubes above or below it, and there will be 2 places where the lines connect to the metal tubes (the ones you traced from the firewall). One will connect to a barb fitting on a plain piece of metal tube, probably at the back. the other connects to the pressure regulator, which looks like a little matal cylinder with a barb fitting sticking out of it. The fuel pressure regulator will have a vacuum line going to it as well. The line you want to disconnect is the one that doesn't go into the fuel pressure regulator.
I hope that was informative without sounding condecending.
Don't forget to put a rag under the line... it should squirt out a little.Comment
-
Ok, figured it out but an easier way of explaining where the hose it to say right underneather the FPR. 2 hoses go up near the FPR and it is the one that doesn't go into the FPR, right? If I am talking about the correct line (I'm pretty sure I am) I unhooked it stuck it in an empty cup and tried starting the car a couple times and half the cup filled with gas. So that is saying that I am getting gas up to that point.
Next step please.sigpicComment
-
Pull a plug off of a fuel injector. Put the clip (ground) of a test light to the positive side of your battery. Touch the point to each pin on the injector harness, to see which one is ground.
Now, ground the test light like normal, and put the point on the prong that is not the ground. Have a friend crank the engine. You should see the test light flashing if you have an ijector pulse. If you dont get any flashing, then your injectors aren't being told to put fuel in.
The fuel injection computer is what tells them to inject, as well as when. It takes input from various sensors to determine this. I didn't own my M20 for more than like 50 days, and I never knew what all the sensors were on it. I didn't see any point in learning them since I wasn't keeping the engine.Comment
-
First off, how do I pull an injector? Second, should I try resetting my ECU by unplugging the battery for an hour or so before I do all this?sigpicComment
Comment