Popping then sluggish performance(01' F4i)

C_J_GO · 08-16-2005, 09:15 AM

So I went to go pick up the g/f the other day and on the way there, I heard a couple loud pops, louder than normal backfire. I stopped to check things out, which I found nothing and the bike was idling fine. So I get back on and continue riding when i notice that there is no power anymore. I have to rev the motor way up when letting the clutch out and the exhaust note is quite a bit deeper(my two bros. pipe has the ricer whine to it). Did I blow maybe some plugs out and am only running on a few cylinders?

edit: Sorry, I have a 2001 F4i..with 6000 miles. i replaced the cct about 500 miles ago

meddling kid · 08-16-2005, 12:58 PM

what speed and rpm were you running when this happened?

when you rev the motor (without it being under load) does it seem to rev okay?

C_J_GO · 08-16-2005, 09:27 PM

i was coming up to a stop sign, downshifting through the gears,,coming from about a 30-35 mph to the stop sign.....
It is sluggish until about 4-5K then it picks up, but tis still not the same.
It doesn't seem to be as bad when ther is no load on the bike, but I can still tell something is wrong...the exhaust note is a definite indicator

C_J_GO · 08-16-2005, 11:33 PM

I just checked the plug wires and they were tight. I tried to take a plug out, but a piece of frame kept me from getting this done. Anything else I should check while the bike is in pieces?

C_J_GO · 08-23-2005, 03:57 PM

I amanged to pull a plug out and it seemed OK, just pretty wet, even after sitting there almost a week. So I put the bike back together and the problem still persists. I didn't have a gas can handy to drain the tank for possible water, so i added some gas treatment to the tank and I am hoping I will run out the problem. Is this typical for water in the tank?

Redstar11 · 08-23-2005, 08:16 PM

Sounds like you are getting a misfire on one or more of the cylinders. You can verify by spraying a bit of brake cleaner on your head pipes when your bike is warmed up. See how quickly it evaporates on each of the pipes. If one evaporates slower than the other, then you know that cylinder is mis-firing. A deeper odd sounding tone is fairly regularly a sign of mis-firing cylinder/cylinders.

You will want to take each of the plugs out and check them for color and such.

You wouldn't happen to be getting any Codes thrown would you?

C_J_GO · 08-23-2005, 09:23 PM

Quote:

Originally Posted by Redstar11

You will want to take each of the plugs out and check them for color and such.

You wouldn't happen to be getting any Codes thrown would you?

How would I check the codes? I've heard something about flashing lights..
What does a good plug look like? I pulled one out and it looked alright(as far as i know) Do you have to go to the dealership to get plugs? How much?
Thanks again for your help..

Redstar11 · 08-23-2005, 09:33 PM

Your MIL (malfunction indicator light) will start flashing. You recognize a short flash or long flash and count them. The number of flashes gives you a code number. Is yours doing that?

A good plug should be dry, and tannish in color. You can go to the dealership to get plugs. They should have them in stock.

C_J_GO · 08-23-2005, 11:48 PM

Well, I just rode around for a while and took the temps of my manifolds, and one pip was about 100 degrees cooler tha the rest, so i found the misfiring cylinder. Do i have to replace all plugs, or just the one? I mean as long as i am in there, as loing as the plugs are not too expensive, i might as well...thanks for all the help along the way...

Redstar11 · 08-24-2005, 12:04 AM

If you have the cash, go ahead and replace them all since you are going to be in there. The plugs aren't that expensive. Just make sure you use whatever comes out. I think you will be using NGK CR9E's.. or CR8E's. Just use the standard NGK's. You don't need all that fancy split fire bullshit. If you replace them all, you will know where you stand at plugs at least. Not to mention they give a good indication of whats going on in your combustion chamber down the road.

However, just replacing your plug may not solve the problem. Something caused the cylinder to misfire. It may be as simple as a fouled out plug, but on an f4i with as few miles as you have, I doubt it. When you have the plug out of the mis-firing cylinder, check to see if your old plug will spark when you have it out. If it doesnt, then we can go from there. MAKE SURE YOU GROUND THE PLUG TO A STEEL BOLT OR SOMETHING BEFORE YOU CRANK THE BIKE TO CHECK SPARK.