ECM correction after new fuel pump

[RidetheLightning]

I've re-installed my rebuilt fuel pump assembly with new pump, and after priming the bike fired up and idled great. Didn't have time for a ride after that, so it sat a couple days. Fired it up yesterday and it idled rough, fluctuating between 800-1500 rpms, and died a couple times. Always fired right back up and idled all over the place again. When it warmed up it seemed to hold idle better, so I took it down the street and it coughed a bunch through the throttle body, backfired, and died. Babied it back to my driveway, and am wondering if maybe the previousyl failing fuel pump had caused the ECM to adjust for the lean scenario, and now needs to be re-calibrated. I was going to re-load my original map that used to run great before the pump died, and re-set TPS as a baseline, but was wondering if this is common after re-installing a new pump. Also, how quickly does an ECM adjust itself? I'll report back how it runs after re-setting the ECM fuel and TPS.

 

[34nineteen]

If the pump was failing and pressure/flow was low, the bike probably saw itself as running lean and fattened up the AFV to compensate. I would also check the plugs to make sure they didnt foul.

 

[RidetheLightning]

If the pump was failing and pressure/flow was low, the bike probably saw itself as running lean and fattened up the AFV to compensate. I would also check the plugs to make sure they didnt foul.

Yeah that's what I was hoping. Was saving the new plugs for when I rotate the engine but may drop em in sooner just to rule it out.

 

[34nineteen]

Yeah that's what I was hoping. Was saving the new plugs for when I rotate the engine but may drop em in sooner just to rule it out.

Just pull them and clean them. I'd get ahead of this now, because once you start the rotate, you will have a million other things on your mind, especially since its the first time. Hey, I was so preoccupied I forgot to install the O2 sensor!

 

[Cooter]

The ECM will adjust AFV pretty quickly and thats certainly easier to check before you open the tune nightmare.

IMO, re-check your work before adding more variables. No shame in making a mistake, only in not looking for it
Did you have the airbox off? Throttle body to airbox base gasket OK?
Was there a few attempted starts before it ran? Fouled plugs. They are easy to swap without a rotate. Use a short length of 3/8" fuel line shoved on the plug as a flexible extension to thread in the new one.
Fuel pump connection OK?
Was the sock disintigrating? Did you get debris in the fuel line?
Did you check for chaffed wires inside?
If it doesn't idle well, it won't run well
Once the little things are checked, I would re-start diagnosis as if I never touched the fuel pump.

 

[upaero]

Hunting idle and coughing through intake are sure signs of a lean condition. Did you replace all of the seals and o-rings on your pump assembly and did you check the fuel pressure afterward? The ECM will compensate for low fuel pressure by raising the AFV dramatically, so fixing the pump would make it run rich until the AFV is dialed back down.

 

[RidetheLightning]

hooked up to ECMdroid lat night and had a battery voltage code. Got my battery tested then charged. Re-loaded my fuel map, reset TPS, and adjusted the clutch cable (something I've been meaning to do already). Tonight I'll check out the plugs, which should be the last thing before I try again. Unfortunately between work and kids I have to work on it in very small increments.

 

[upaero]

hooked up to ECMdroid lat night and had a battery voltage code. Got my battery tested then charged. Re-loaded my fuel map, reset TPS, and adjusted the clutch cable (something I've been meaning to do already). Tonight I'll check out the plugs, which should be the last thing before I try again. Unfortunately between work and kids I have to work on it in very small increments.

Checking your AFV should always be step 1 and can be done in about a minute. If it adjusts itself to a number significantly higher than 100 that is normally indicative of low fuel pressure. When you load a new "map" it is usually defaulted to 100. If the fuel pressure is low it may not even start at 100. If you adjust the AFV to say 120 and it starts then you know you have a fuel problem.

 

[RidetheLightning]

Checking your AFV should always be step 1 and can be done in about a minute. If it adjusts itself to a number significantly higher than 100 that is normally indicative of low fuel pressure. When you load a new "map" it is usually defaulted to 100. If the fuel pressure is low it may not even start at 100. If you adjust the AFV to say 120 and it starts then you know you have a fuel problem.

Just realized I never said, but I checked it and it was 83.5% before I re-loaded my map. Got the new plugs in except I'm still struggling to get the boot back on the rear plug. Any tricks would be greatly appreciated.

 

[upaero]

Ah, ok. At the ~1100' elevation of Phoenix 83.5 is very low, and explains why your bike was running so bad. It's very common (more often than not I would bet) for these bikes to run unnecessarily lean because the ECM thinks the bike is going up a mountain. Reset the AFV to 100 and keep an eye on it to make sure it doesn't go down below about 98. I run my bikes in open loop with the O2 sensor still active to warn me of a lean condition , instead of allowing the ECM to adjust for it. rev-mo.com/openloop. What exhaust and mapping do you have? The EBR tune for the Jardine muffler has a nasty tendency to do exactly this. That causes a lot of decel popping which eventually causes the can to come apart.

 

[34nineteen]

Got the new plugs in except I'm still struggling to get the boot back on the rear plug. Any tricks would be greatly appreciated.

There are some specially designed spark plug boot pliers available to make this job a snap. Also make sure you have coated the inside of the boot with dielectric grease.

I've used an open end wrench (I think 1/2 or 9/16) to sort of grasp on to the boot in a pinch (aka too lazy to get up and go back to my tool box). Just be careful with this technique.

 

[RidetheLightning]

There are some specially designed spark plug boot pliers available to make this job a snap. Also make sure you have coated the inside of the boot with dielectric grease.

I've used an open end wrench (I think 1/2 or 9/16) to sort of grasp on to the boot in a pinch (aka too lazy to get up and go back to my tool box). Just be careful with this technique.

Good call on putting dielectric grease in the boot. I just put a little on the top of the plug and I'm sure most of it came off when I used the fuel line to help thread it in. I'm sure I have those goofy pliers around somewhere too, just didn't need them for removing the boot since I was able to get my fingers far enough up there to pop it off from the bottom.

 

[RidetheLightning]

Ah, ok. At the ~1100' elevation of Phoenix 83.5 is very low, and explains why your bike was running so bad. It's very common (more often than not I would bet) for these bikes to run unnecessarily lean because the ECM thinks the bike is going up a mountain. Reset the AFV to 100 and keep an eye on it to make sure it doesn't go down below about 98. I run my bikes in open loop with the O2 sensor still active to warn me of a lean condition , instead of allowing the ECM to adjust for it. rev-mo.com/openloop. What exhaust and mapping do you have? The EBR tune for the Jardine muffler has a nasty tendency to do exactly this. That causes a lot of decel popping which eventually causes the can to come apart.

Yeah I have an open airbox K&N w/ Jardine RT1, and buelltooth map for it. It had previously been dead on at around 100.7 I think before it all went to hell when my fuel pump died. Pretty sure everything will be just fine once I fire it back up, just wanted to check if this was a relatively normal symptom since I've never had as severe issues while riding. Should get it all buttoned up tonight.

 

[upaero]

Yeah I have an open airbox K&N w/ Jardine RT1, and buelltooth map for it. It had previously been dead on at around 100.7 I think before it all went to hell when my fuel pump died. Pretty sure everything will be just fine once I fire it back up, just wanted to check if this was a relatively normal symptom since I've never had as severe issues while riding. Should get it all buttoned up tonight.

Yes you should be fine as long as the AFV doesn't drop again. Don't be afraid to try open loop with the AFV at about 103. It will help drivability and run cooler with negligible effect on fuel economy. You can always revert back to the original version in seconds. If you're happy with how it runs in OL you can add a baro sensor for proper and continuous elevation compensation in the hills and mountains. Also, that's not a "Buelltooth" map, it's the EBR calibration for the RT1.

 

[RidetheLightning]

Alright so took it out again with new plugs, TPS reset and re-loaded map. Ran perfectly smooth and strong...right up until 4k rpm again. It wasn't as severe, but did cough, eventually backfire, and die on me. Fired right back up and cruised home. Codes are as follows:

15 - Air temp too high / short to ground
33 - Fuel pump short to ground
21 - AMC stuck open
21 - AMC stuck closed
21 - AMC short to ground

Next step is going through the service manual (sine I know that comment will be here soon enough haha, but any guidance is appreciated. Obviously checking grounds too. negative battery and cross bar braid are good. I believe that leaves only the one under the triple tree, which may explain past random blinker and horn intermittent failures. Could this ground affect the issues above (i.e. do all ground affect all operations), or are they for specific areas? My main worry is having to hike the bike back up in the air and pull the pump all over again. I made sure to connect the ground well on the assembly, but am wishing I inspected the wiring more thoroughly before plugging everything back up.

 

[Cooter]

Are those current or historical codes? Ignore code 21 and might as well turn on error masking for it while you're in ECMDroid.

 

[RidetheLightning]

Are those current or historical codes? Ignore code 21 and might as well turn on error masking for it while you're in ECMDroid.

Ah, right. Forgot my map re-set that masking I had previously switched. They are current. There were no codes before the ride.

 

[upaero]

Alright so took it out again with new plugs, TPS reset and re-loaded map. Ran perfectly smooth and strong...right up until 4k rpm again. It wasn't as severe, but did cough, eventually backfire, and die on me. Fired right back up and cruised home. Codes are as follows:

15 - Air temp too high / short to ground
33 - Fuel pump short to ground
21 - AMC stuck open
21 - AMC stuck closed
21 - AMC short to ground

Next step is going through the service manual (sine I know that comment will be here soon enough haha, but any guidance is appreciated. Obviously checking grounds too. negative battery and cross bar braid are good. I believe that leaves only the one under the triple tree, which may explain past random blinker and horn intermittent failures. Could this ground affect the issues above (i.e. do all ground affect all operations), or are they for specific areas? My main worry is having to hike the bike back up in the air and pull the pump all over again. I made sure to connect the ground well on the assembly, but am wishing I inspected the wiring more thoroughly before plugging everything back up.

The air temp sensor and fuel pump codes are remnants of having the bike turned on while those were disconnected, so you can disregard. The AMC error mask should already have been unchecked, but isn't affecting how it runs. Did you check your AFV again? If it's doing the same as before it probably adjusted itself back down while you were at cruise speed, which is where the "learn" area of the mapping is. You can actually watch AFV, EGO correction and everything else going on with the ECM in real time, even while riding (if you're careful). rev-mo.com/livedata

 

[RidetheLightning]

Fired it back up in the driveway, and was able to immediately replicate the issue the second revs got above 4k. Backfired a couple times then died. Threw a code 56 - sync failure this time. No other codes.

 

[RidetheLightning]

After doing some digging on old threads it sounds like the crankshaft position sensor may be the issue, and symptoms sound similar to mine. My bike has had a slight hiccup under hard acceleration at higher rpms for some time now, but wasn't coughing or backfiring. Only recently did it get this severe. It sounds like other people have had issues, sometimes never getting trouble codes related to it, but progressively running worse. While I still think my pump was most likely failing, the CKP sensor going could be what's confusing me. Going to go through the diagnostic procedure for this and see what's what.