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DISCUSSION => General Topics => Topic started by: 318isbest on July 31, 2013, 05:58:39 AM

Title: check engine light.......help please
Post by: 318isbest on July 31, 2013, 05:58:39 AM
 hi everyone I have a 95 318i  and I just got on the road and come to find out I have a check engine light  I do the stomp code and I get 1222 which is the lambda sensor  and I can't figure out what's causing it I have replaced spark plugs fuel filter o2 sensor which is a three wire Mustang  sensor and I've checked all the hoses on the hood they look relatively decent I don't see any cracks or leaks in them  when I reset the computer the check engine light doesn't come on right away it it comes on after the car reaches about quarter weigh on the temperature and then the light comes on  I'm also getting code 1262 which after reading is something to do with the ICV  I have it clean that I forgot to do that yesterday when I had everything apart...... my main concern is going by the onboard computer I'm getting 15 mpg which bothers me because my last one I was getting roughly 40  the miles per gallon gauge on the cluster everytime I press the gas  bottoms out about 10 miles per gallon  any help would be greatly appreciated guys I need better mileage to fix all these problems
Title: Re: check engine light.......help please
Post by: DesktopDave on July 31, 2013, 08:47:22 PM
Your code is likely just from the mixture being too rich.  I'd bet your O2 sensor is fine.  A 1222 could also be a failed heater relay.

I'd check carefully for any vac leaks again, but it seems like you've done that already.

Be sure your coolant temp sensor has a good reading, and also check the fuel delivery - fuel pump pressure, fuel pressure regulator.  Replace the  injector o-rings while you're in there - those can have vac leaks as well.

That onboard MPG computer is just a calculator - it measure injector bandwidth and divides it by a MPH signal from the computer.  It's not accurate, just a ballpark figure.  Mine hits 15MPG all the time, but when I use the odo against gallons used, I average 31MPG.
Title: Re: check engine light.......help please
Post by: 318isbest on August 01, 2013, 06:52:47 AM
thats what I figured is that the obc is just weird what about the range one I just put in 10 gallons and it said that id only go 150 miles is.that just a calculation also.......im pretty sure I.have no vaccum leaks I sprayed the whole motor and.no rpm increase o and an off topic question why are there vacuum lines on my fuel injectors
Title: Re: check engine light.......help please
Post by: DesktopDave on August 02, 2013, 09:25:39 PM
Those aren't vac lines on your injectors - they're an air injection system meant to improve emissions.  Here's a good link explaining the system (http://bmw3series.johnavis.com/blog/default.asp?id=653).