Hello interested people,
I have been having the Check Engine Light come on recently and was hoping the symptoms might ring a bell with someone. I know I should "take it to the man" and get the codes read, but my local indy mechanic has closed up shop, and the local dealer has moved to a PITA place and I will need to take a day off work.
2007 S4r, no mods apart from Termi shorty exhaust. Last service was major with cam belts replaced.
CEL comes on with level throttle over 5k rpms or so
Does not come on while under acceleration over 5k rpm, just when "close the throttle" after acceleration
The CEL will turn off again as soon as I decelerate and I pass exactly 4k rpms.
The bike itself is running fine. Level throttle is nice and even. Performance still fine, I can't fault the engine otherwise.
I wondering if its TPS, or just a sensor that has some logic to stop sensing below 4k rpm... I know its a stretch... but thought I'd ask before taking a day of work to hang around industrial areas (new dealer location).
I have an 07 S4R and it shut off on me once in slow traffic. Replaced the rectifier with a MOSFET design and no more problems. I was going to do it anyway so it's not like I was guessing and throwing parts at it without diagnosing. It just happened that there were no running issues afterward. Weird. Replacing the stock rectifier should be one of those things that everyone does as a matter of course, because the stocker gets extremely hot under the seat and basically cooks itself to death. Bike's reliable now.
Which one did you buy?
Derek V
Before going out and buying anything get someone with a scan tool see if there are any stored codes and do a charging system check. Installing a voltmeter could be a good idea too so you can observe what happens to voltage while riding. Yes, your regulator is a probable cause and Mosfet is a good upgrade, but don't you want to confirm the problem first?
Quote from: howie on February 14, 2018, 09:38:05 AM
Before going out and buying anything get someone with a scan tool see if there are any stored codes and do a charging system check. Installing a voltmeter could be a good idea too so you can observe what happens to voltage while riding. Yes, your regulator is a probable cause and Mosfet is a good upgrade, but don't you want to confirm the problem first?
Wait - I read OPs post wrong. The CEL turns off not the engine. Yes, pull the codes first. Sounds more like an O2 sensor malfunction perhaps.