X5 3.0i Poor Start

salenks · #1 07-22-2012, 10:50 AM

Hello,

I was wondering if anyone can help me with the issue I've been having.

My 2003 X5 3.0i sometimes starts like it only fires up a couple of cylinders and then a second or two later, the rest of them. This happens occasionally, not every time. I also noticed smell of gasoline when this happens.
I have been having issues with the battery where the voltage drops to 12.3 V and from what I've heard, it should be 12.5 or more volts. This is not the original battery but a Exide 72Ah/720A and same happens with another battery which is Optima 50Ah/815A. Could low battery voltage cause this? Or what else could be the problem?

I added the recording of engine sound to youtube

http://youtu.be/Zr1XXcx1YWs.

Little history of my X5:
-105,000 Miles
-Spark plugs changed at 95,000 miles (orignal installed)
-LPG installed (had to remove original battery because of this and place new battery in trunk side compartment)
-Replaced fuel pump with one for Opel vehicles (has 3.5 bars and BMW has 3 bars pressure)

I was told by a mechanic that this fuel pump will do the job but I am not so sure. I will probably get the original in a couple of weeks.

When the mechanic hooks up the computer to the car, there are no error codes regarding this problem. There are some error codes but those are normal when you have LPG installed.

Thank you all for your help,

Sasa

SlickGT1 · #2 07-22-2012, 10:54 AM

If you smell fuel, you are not burning it. So start with the spark plugs. Coils would give error codes.

salenks · #3 07-22-2012, 10:58 AM

Thanks for your reply.

Spark plugs were changed about 5-10k miles ago with original ones. Forgot to mention that in the original post. Fuel probably smells because not all the cylinders fire up when the car is started.

SlickGT1 · #4 07-22-2012, 12:16 PM

Ok. Could be your 3.5 bar fuel pump is flooding the cylinders.

What condition is your air filter in?

salenks · #5 07-22-2012, 12:21 PM

Thanks for your reply. Air filter (k&n) was cleaned about 2,000 miles ago but i will check it.

SlickGT1 · #6 07-22-2012, 12:34 PM

Hmm. Disconnect your maf and try staring the car. Let us know if it starts better.

salenks · #7 07-22-2012, 12:42 PM

I will try that. I know i can't drive it like that since it is automatic. I also have a replacement maf that i paid 90$ for. I know it is not original but it is for my car. Maybe i can replace it.

Thanks.

What about the battery voltage. Could that cause the problem?

SlickGT1 · #8 07-22-2012, 02:29 PM

deff could be.

Have you tried unlocking OBC, and running the voltage test while driving? Search here, use the search button on top, search for "Unlock OBC". instructions are easy and there. Then run the voltage test.

Report back what you observe.

Also, does it start fine after driving, or same deal?

salenks · #9 07-22-2012, 02:36 PM

I will try that. However, voltmeter says battery has 14V when car is running which means it is charging properly. Same deal after longer drive. Batteries are definatelly bad in my opinion. Warranty sucks here in Serbia though.

J-FEEZY · #10 07-26-2012, 05:12 AM

Quote:

Originally Posted by salenks

Hello,

I have been having issues with the battery where the voltage drops to 12.3 V and from what I've heard, it should be 12.5 or more volts. This is not the original battery but a Exide 72Ah/720A and same happens with another battery which is Optima 50Ah/815A. Could low battery voltage cause this? Or what else could be the problem?

Sasa

Quote:

Originally Posted by salenks

I will try that. However, voltmeter says battery has 14V when car is running which means it is charging properly. Same deal after longer drive. Batteries are definatelly bad in my opinion. Warranty sucks here in Serbia though.

which is it dude? is it 12.3v when the car is off or the car running? OR is it 14v when the car is running and 12.3v when the car is off? OR is it 14V while the car is running and you had a volt meter on it and saw the voltage drop to 12.3V Whats really going on?

I believe you when you say it sounds worse on the recording than standing next to it. makes sense.

If its me i'd get the "oem genuine bmw" from ecs tunning. they are $3 bucks more each. I like to go oem on that kind of stuff untill something else is "proven" to blow it away. those other ones look OE replacement which you can find on esc tunning for alot less. just sayin

The problem I had was the sound you have but ya you can't really notice right away that your shiz is running like crap. I also had the infamous hesitation in the throttle from a stopped position. There was a guy on here the other day and his explanation of what his symptoms were was exactly Word for Word how I would have explained my issue. He even said he had a misfire on cylinder 3. Some dude comes in and tells him its the torque converter and off he went and made an appointment with a tranny shop... guess what he got.. a new converter! you think that solved his misfire problem too? LOL

disclaimer: I have no idea if coils are going to solve your problem. I can only tell you what happened to me. When I put new coils in my shiz my shiz ran great. The problem in the throttle hesitation was no longer there and the sound of the engine running improved noticeably.