I just bought an 01 F4i, 18,000 miles. It's not running right, and I'm not sure where to start. The only thing that's not stock (as far as I can tell) is the exhaust. The previous owner had already done quite a bit to it, here's a list.

- Replaced injectors, fuel rail, pressure regulator, and fuel filter.

- Replaced MAP sensor.

- Swapped ECM, I have the spare, it currently has the original because it did not run differently with the spare. I'm not sure where he got it but it's a california ECM and the bike isn't a california model, don't if that matters.

- Replaced spark plugs.

None of these things have made the bike run any better.

Here's what it does:

If I hold the throttle wide open and crank the engine over, it will start, but idles rough jumping between 1000 and 1500 rpm.

If I push it (actualy I would have to roll it down a hill at about 20 mph) and dump the clutch in first gear, it will start, and if it's above about 3500 it will run with the throttle wide open, and rev up to about 6500 - 7000 rpm. I drove it this way up to about 65, it just boggs down when it gets to about 7000.

Once it is warmed up, if I start it with the throttle wide open, it will idle rough, slowly (and roughly) work it's way up to 3000 - 3500 rpm then it will start to run great and red line. But if I am driving it (there is a load on the engine) it boggs around 7000.

I haven't gotten a chance to tear it apart yet, but I'm hoping to do so tomorrow night and was wondering if anyone can point me in the right direction.

Thank You for your help.

 

Try some sea foam. I only gotta go 7mph to bump start mine.

 

I'll give that a try. I gues what I meant about bump starting it is I have to get going fast enough that when I do let the clutch out I get it above 3000 rpm, because it wont run below that.

 

Ah, I see. I've been riding on a dead battery for a while, so I've learned to mount, run, pop the clutch.lol

 

I had a chance to dig into it tonight, here's where I'm at,

- The injectors have the specified resistance, I'll assume they're ok.

- IAT sensor is ok.

- TPS seems to be ok. I hooked up a multimeter to measure the resistance, as I twist the throttle the resistance changes, I'm guessing this is right. The resistance went from 870 - 4700 ohms. I'm not sure what the spec is for this.

- The engine coolant sensor had a slightly low resistance reading.

- I did notice that the ECT and MAP sensors had a high voltage. Spec is around 5 and they had about 7 or 8 volts. Maybe my spec is wrong??

- I checked the FI code(s) and got the following:

1 - Map Sensor
2 - Map Sensor
8 - TPS
9 - IAT
12 - Injector 1
13 - Injector 2
14 - Injector 3
15 - Injector 4

I'm having a hard time believing that all of these things are bad. I'm starting to think that maybe the original and replacement ECM are bad.

The spark is also strong. I took the plugs out and they were wet with gas.

I'm running out of ideas and patience, please help.

 

it sounds almost like it's off time

 

I'm going to check the timing and compression today when I get out of work... Not sure where to look after that.

Thanks for the help.

 

Wow, you were right, the crank had skipped a tooth. Fixed the timing and it started right up.

Thanks!!

 

Sweet...gotta love it when folks get their sht fixed and actually tell us, instead of just riding off into the sunset. ride safe bro.