Check engine light

[jdtech65]

I was riding my 2010 D-8 back in Iowa today - elevation around 1800- and I was noticing a stumble or hesitation around 6800-7000. You definetly noticed it was there but you could give it a little more throttle and get it to come out of it. Later though I noticed it was getting worse and I looked down and saw the check engine light flashing. It wasn't really flashing a blink code though. A couple weeks ago I had my Exhaust temp sensor go bad so I know how that flashed. This was just a constant very fast flashing. There was no pauses in it to count the flashes. I shut it off and restarted it and it never came back in the 2 miles to get home but the hesitation was still there.

Whats the fast flashing mean? Could it be detonation? I had probably 5 gallons of 91 still in there from the snowies last week where it ran perfect at 9000 ft and then another 6 gallons of 87 non ethanol from here in iowa where I always fill up.

I am going to order a PC-V for it on monday. This is the first time I've riden it back here in a low elevation but out West from 8-10,000 it has ran good for 300 miles so far.

 

[shabs]

ya its det if your riding around that rpm range, if it blinks fast or the light stays on its det. Try using just 91 oct with ethanol wires unplugged, these 4 injector 800 motors love octane and are very moody.

 

[ragincajun]

i had the same problem but it was doing it up high. turns out i had a crappy ecu map that made the det senson waay too sensative and would make it go nuts. got the new reflash last week and so far so good.

 

[jdtech65]

I was thinking it was detonation but wanted to make sure. I did unplug the ethanol wires today and that helped quite a bit. I usually run 91 but I didn't have time to run to the next town to get 91. Most stations here just have 87 non ethanol and 89 with 10 percent ethanol.