Hellpp!!!small but big problem

[Hmf Ds450]

My quad will be running perfect for hours even days and it will just randolmly bog out with out no sign, the engine light goes on immidiatly after the bog, it's very dangerous becasue it bogged out at the lip of a 70 foot table which I nose dived, I have added new gas several timesbecause I thought it was bad gas but it wasn't , the oil was preetty dirty could that make it bog, and the throtle body was somewhat dirty , I need to know why it is bogging out randomly at higher rpms????? Please

[bomberman]

Sounds like its going in to limp home mode. Check the coolant level. Check the radiator is clear.

[joeyds450x]

mine does it too but it does it even when i just start riding.. theres no way itd overheat that fast?? took it to the dealer lol

[bomberman]

sometimes the dealer will need to reset it

[Hmf Ds450]

reset what does it cost much?

[Hmf Ds450]

yeah its usually half way between rides, it not getting to hot though i kknow, and its getting so dangerous when you hitting jumps and you got no throttle at the lip lol

[Hmf Ds450]

so do i take it to dealer and say reset my limp mode

[florentino]

Originally posted by Hmf Ds450
so do i take it to dealer and say reset my limp mode

yes but if you have the 2008 they can put the 2009 program its better.

if they reset limp mode can come back if you dont fix the problem.

so engine ice is a must for the ds.

fan on at all times works for me.

wrap the exaust heather with that heat tape.

make sure you have a clean filter

check the batt cables

i had limp mode and after i did all this mods it when away and never came back and i ride hard and even race it.

one more thing make shure radiator is super clean.

so you have pink wire cut ? what exaust?

[Hmf Ds450]

Wire cut, hmf slip on, velocity intake ,I have an hmf optimizer but not installed currently, does it cost much to change the limp mode thing

[Hmf Ds450]

How do you keep fan on at all times

[florentino]

Originally posted by Hmf Ds450
Wire cut, hmf slip on, velocity intake ,I have an hmf optimizer but not installed currently, does it cost much to change the limp mode thing

to change the limp mode or to flash it cost the same. the bad part is that most dealers dont have a clue.

to keep fan on at all times i hot wire it mine to my lites swich to i can turn it on or off really cool set up.

i dont run lites in my ds.

after you do all of this you may not have to take it to the dealer i never did. but disconec to batt cables for a day. sometimes the computer resets it self.

it work for me. i know that you can also send your box that controls that and they can remove limp mode if you are a harcore racer thats the only way to go

[Hmf Ds450]

Is it difficult to wire fan to light switch . I took my lights off aswell

[florentino]

Originally posted by Hmf Ds450
Is it difficult to wire fan to light switch . I took my lights off aswell

theres 3 wires at the end of your lites you only need 2.

the fan motor has only 2 ground and hot.

just remember that the fan can pull or push air. make you that when is runnig its pullin air.

i reconment taking your plastics out so you can see better.

test your fan with a 12 volt batt. by it self to make shure it works.

its also a good idea to have a voltmeter.

dont forget engine ice. i dont know where you live.

i live in california and i dont need too much antifreze.

did you know that too much antifrize will make your motor run hot.

you know there s a problem with the gas tank and you need to protec it so fuel is cooler and yes cut some holes on the plastics around the gas tank.

[Hmf Ds450]

Would installing my hmf fuel controller bypass the limp mode. And what do I ask when Iget to the dealer, like" reset my limp mode"?

[TNT]

Originally posted by Hmf Ds450
Would installing my hmf fuel controller bypass the limp mode. And what do I ask when Iget to the dealer, like" reset my limp mode"?

The ECM and fuel controller don’t talk or see one another, they don’t interact. The ECM use to deliver fuel signals to the injector, now you’re HMF does by intercepting the ECM signal or pulse. HMF does not send info back to the ECM so it can not prevent limp directly, can indirectly by the fuel map that keeps the motor cool or not running lean.

Limp home mode is in the ECM, a protection program that based on coolant sensor temp input limits certain engine functions or revs to allow limp home. Those temps for 08 are 226F/5500 rpm; 09 248F/8000 rpm. Rev limits if you will and there are others on the DS(there are other rev limits, electrical over/under charge, fuel drowning mode, and max speed), nice thing about an EFI engine management system lots of fail safe modes, but I think yours may be temp limp home related based on what you described. If you want to keep limp and have an 08, it’s wise to get the dealer update to 09 values or you will see it too often….good for trail riders.

Racers such as you need to get it completely removed. Last I was aware only BRP race dept or program can do that not dealers through BUDS. You have to send your ECM to Canada they have to reprogram it, they send it back you pay shipping and handling and a small processing fee…around $75 but call them for more accurate updated info.

Not totally sure this is your problem. If you have been running fine and this started up all the sudden you may want to visit the dealer get on BUDS and see what diagnostic codes are in your ECM and while your there get the 09 update/flash dealers can do in BUDS. If you normally don’t run hot as you say this may suffice. If you are running normal and functioning properly and you still go into limp it means you either are not maintaining the cooling system to prevent it, controller is running lean, or some other cause, or you have enough mods and riding ability to hit limp dangerously too often time to be safe get it removed.

Hope that helps, a little confusing this quad I know. :D

[allbones512]

If you want all the little problems to go away i would suggest sending your wire harness to bcs performance. They take out all the unnecessary wires, for example the lights and the fusses, and they make it so that your fan will say on all the time and i would get the race computer too, to replace the stock computer. I'm sponsored by bcs and i had everything done by them and i havn't had a single problem with my quad since.

[400exc]

I don't want to steal anyones thread, but how often does the limp mode occur on 08's? I have had mine since August and haven't had this happen yet. I plan on going to Hatfield and riding the hills, and do not want to be climbing a hill and then it goes into limp mode. How hard does someone have to ride it in order for this to occur?

[florentino]

Originally posted by 400exc
I don't want to steal anyones thread, but how often does the limp mode occur on 08's? I have had mine since August and haven't had this happen yet. I plan on going to Hatfield and riding the hills, and do not want to be climbing a hill and then it goes into limp mode. How hard does someone have to ride it in order for this to occur?

if you have low water, or radiaror ir dirty with mud or fan not working or a loose batt cable. but the main one is overheating.
once you figuere it never comes back.
yes limp mode sucks. it only gets better once your frame breaks
but i do ride hard.