Help - Honda can't. Running rough and red pipes

Hi all

Got a 02 Vfr 800 vtec. It's running rough upto about 3000 rpm and the back downpipes are glowing red. With and without pciii.

Honda have just had it for six months checked timing fitted a different wax stat and charged me a fortune for fuck all progress.

Any one got any ideas?

 

What is the engine temp showing?

 

Seemingly any temp from cold to 107 when the fan kicks in.

 

Once warmed up, the bike should never drop below 168F or ~75C even when riding in freezing temperatures. If your bike is dropping below that temp when riding, check your thermostat. (You said wax thermostat so I'm not sure if they changed the FIWU or thermostat or both) The ECU does some really REALLY messed up stuff trying to get the bike to stay at optimal temperatures if the thermostat is stuck open including vast changes in fuel ratios.


You say that it does it with or without PCIII. What mods have been done to the bike? Stock exhaust? Stock headers? With or without O2 sensors?

Have you checked check engine codes that may or may not be lighting up the dash?

Lot's more questions to come I'm sure from lots of people but these are basic ones to start with.

 

Good idea. Not too terribly hard to check either but will require opening the heads IIRC.

 

For the pipes to run red hot, then the fuelling is way off or the timing is bad & getting live firing in the exhaust !
You said Honda had it, by that I assume you mean a dealer ? I'd contact Honda if the dealer has had it & not rectified the fault, but charged you. You are NOT obliged to pay for repairs where they fail to rectify the fault well in the UK anyway.

If you are not confident to do the diagnosis & repairs, then find a VFR expert near you that can help.

 

Sorry should have specified. It gets to 107 c.

 

Hi guys. Stock every thing except collector box and pciii. Loaded the standard pciii map to it.

 

We need more info. How many miles/kilometers on this bike? Have valve checks been performed? Did this happen all of a sudden while riding and was it accompanied by any other noises before hand?

 

Hi. Yes honda have checked the timing and vales. Changed throttle bodies. It's idling rough will rev to about 2250 rpm then shoots upto 5/6000 rpm even though the throttle is being very slowly opened. Very difficult to get it to steady rev at 3/4000 rpm.

Any one know and Vfr specialists in north west uk?