Hello Everyone, I am a new member reaching out for some guidance. Here's the issue. I recently purchased an '01 530i with 160k, when starting the car cranks for a bit but takes about 5-10 seconds to catchand runs perfectly after. The battery has checked out fine and the vehicle has been very well maintained. This only happens when the car sits for over an hour. Any thoughts as where to start?
Have you had the codes read? You might have a code in there. I had a similar symptom with a 2.8 Z3 and it eventually threw a CEL and it needed a new cam position sensor. Good luck.
To be continued....Continues on I am slowly receiving bits and pieces of repair history from the mechanic that worked on my vehicle (previous to my ownership), as of now he said he replaced both cam position sensors in the vehicle. So, anybody got another suggestion as to why the 530 is struggling to start? I am hoping the entire repair history will arrive in few days and maybe give a few clues. But until then, any direction would be helpful. Cheers, Adam
Adam, I can see your frustration. This problem alittle difficult to diagnosis without seeing in my opinion. I am trying to prevent you from throwing a lot of parts at this car. But lets try to check some basic things, first. Check condition of spark plug and verify correct type plug for your car. Note: check compression while all the plugs are remove. You will be one step ahead of the game. Fuel quality and pressure, how long has the fuel been in the tank and if pressure is leaking down or restriction. When started, any check engine lights? Verify that check engine light comes on...when starting car...then one for a few seconds...then goes out. Finally, check (air filter and anything blocking air flow sensor) if vehicle has enough air to breath, fire to ignite fuel and engine can exhale through the exhaust. How many miles?
Thanks to all of those people whom replied to my sick 530 question. I will take a look at the plugs and compression as well as the turning the key and waiting for 5 seconds. Another enthusiast suggested I take the car to a dealer and have the computer flashed. I guess I'd like to try a few more things on my own before I get a dealer involved. Like I said previously, the car was meticulously maintained. With regards to the mileage question......160k. Thanks everyone......To be continued
I take it waiting in ON before START had no effect. That was to give the fuel pump to come to pressure in case the pressure regulator was faulty. Does it turn over strong or weak? I know you said the battery was checked but I have little faith in the average battery tester. Several people have had partially bad batteries pass those tests. My next suggestion, because "it don't cost nuthin", is to jump start it and see if the problem persists. Alternatively, you could let it sit on a charger for the hour or so it takes for the problem to occur.
Starts very weak Yes, even letting the key in the ON position for 5 secs then turning to START the car struggles. I did notice the last light to stay lit on the dash board is the battery light and it eventually goes out after about 5 - 10 secs. It sounds as thought the car is gasping for air until I give it a tap on the gas and it idles perfectly after that. Should I replace the battery anyway and see what happens next? I am perplexed as to why the 530 isn't throwing a code!
I wouldnt go as far as replacing it unless it is due anyway (4yrs old). Just jump start or put it on a charger for a while before trying to start. Jump start is best putting it on a charger wont always work expect that yours works if onlt left for less than 1 hour. Also, watching the battery voltage during a start will help ID a bad battery.
bmwstepinstructor, What would be the best way to clean the air flow sensor? I have heard a few ways including some sort of solvent, gas and canned air. Thanks, AK
Wow..this just happened to my bmw 2003 530 yesterday...now it won't start at all. It's at the dealer right now and they are replacing the starter....we will see if it works tomorrow. This is the 2nd time, the first time they reset the computer module...worked for about 2 weeks...then it happened again. Now they say it's the starter...they are sooo lucky I have an extended warranty. I will keep you posted.
Starting Issue Continues on........ Well, here's the latest.........Changed the air filters all around, Cleaned the MAFS with the suggested cleaner. Still no change in the starting problem. BUT, I did receive the service records from the previous mechanic and they suggested replacing the Throttle Body Control Unit.This puppy is around 300 bucks? Any Suggestions?
I replaced my ECU module, and it only fixed it for about 2 weeks. I replaced the starter, and it's been running strong for 1.5 weeks now...replace the starter. Is it turning over when you start it?
Starter Yes, it starts eventually.It sounds as though it cranks and cranks and finally catches and idles a little rough until I tap the gas a little. Is there somewhere I can have the started tested? Autozone? The starter isn't making any of the ordinary death sounds that are associated with a dying strater. Worth a look. TBC........
I would bet money that the fuel pump check valve is allowing the pressure to bleed down, leaving the key on before cranking does raise the pressure, but not enough to compensate totally for the loss. Before spending money on any parts or diagnostics, buy a fuel pressure guage, leave it connected and observe the pressure at one hour intervals, it should hold pressure (3.5 bar, I think) overnight, even though the pressure jumps when the key is turned to on, those that don't hold pressure almost always exhibit a long crank. To verify this diagnosis, you can jump the fuel pump relay and run it for 10 seconds or so, it should fire immediately. Bmw offered an in line check valve for a recall on the E38, if you can get one, it's way cheaper than a pump.
Check Valve appears to be ok Just ran a few tests on the check valve and seems to be ok. Anyone have further suggestions as to why my 530 is struggling?