Need help trouble shooting turbo rx1

[Freak]

So my turbo rx1 takes forever to start, when it does I have to pin the throttle and then it barely keeps running. If I sit and feather the throttle really hard and fast it will SLOWLY start to rev up after about a few MINUTES literally. Then it just runs crappy. If I let it idle down it starts all over again. What is it? We had a larger charge tube and went back to 2", no change. We had a smaller pick up for the float bowls and had it in the airbox, we changed to a 5/16id pick up in the middle of the 2" tube, no change. Im wondering if there is carb damage or blockage. Just wanted to post this to see if anyone could recognize these symptoms before I tear into things. Ohh if I could just go back and use the "If it aint broke dont fix it" method ......

 

[M5-]

Sounds just like when you roll an Rx and it floods. Check your fuel pressure at idle it should be set around 4-5 psi. Maybe your fuel pressure reg took a crap.

M5

 

[Wheel House Motorsports]

yeah, htat sous like what happens when I roll mine.

when you go to crank it it sort of burbles and stutters and you have to carefully work the htrottle to get it going, it slowly(VERY) gains RPM then sounds like it has a stutter button then revs up and clears out??

the interesting part is when mine rolls, it needs LOTS of fuel, the plugs are dry, for some reason it lean stalls when rolled. seems like it could be some sort of fuel delivery issue?

 

[NM]

Does the RX1 use a throttle position sensor? It sounds like what the Apex does when the TPS is shot.

 

[M5-]

Does the RX1 use a throttle position sensor? It sounds like what the Apex does when the TPS is shot.

Not in the sense you would see with a fuel injected system. The sled has a throttle postion switch is basically an on/off thing used to prevent run aways via the TORS system. There is one switch on the flipper and another on the carbs. If you don't have the TORS bypassed the two switches need to in sync or the TORS system will only let the sled rev to about 3300 rpm but up to the 3300 it will run clean.


I miss my Rx1.
M5

 

[Givemeaboost]

Try starting it without the intercooler on it and see if it still does it. My guess is the turbo isn't spinning or blockage in the charge tube. Ken...

 

[0007]

Do a leak down
U might be needing to do the exhaust valves
They lose a lot of signal strength when the valves leak and this shows up mostly at low speed and startup

 

[roughrider99]

symptoms are somewhat similiar to buddys rx1 that had a fuel regulator take a crap.

 

[Freak]

fuel pressure is correct, reg ok. Found a pinched slide diaphragm and we put a baffle in the intercooler as well as an equalizer tap in the airbox. It is running much better now. Going to take it up on the mountain and see how it does.

 

[summit-x]

hope it runs freak sled is extremely fast