Getting only 12.6v

[Rockenrog]

I was getting a maintenance light. Then I put in the fuel pump, it seemed to help but still won’t go over 30, but the surging was way better, just wouldn’t get up and go. Any ideas?

 

[mikidymac]

There are two Quantum pump numbers, one is reported to work, one does not.
There was a thread recently on it but can't remember.

 

[Rockenrog]

There are two Quantum pump numbers, one is reported to work, one does not.
There was a thread recently on it but can't remember.

How can I find that?

 

[mikidymac]

2001 GTX DI - Fuel Pump

 

[Rockenrog]

Updating this thread. Still need help. I have now put in a new fuel pump and still have the same but now kinda different problem. When I attached the key it goes to 65Psi then falls back down in increments of around 5 psi to 0 in less than about 3 seconds. The ski will still start but has the same problem surging and will only go around 30 psi running is only 100 please help,if you can.
Roger

 

[WaarrEagle]

65 psi with only the key points to a bad fuel regulator as it should hold to +27 psi over air pressure. You may want to take the fuel rail apart and check for sludge/clogs/etc.

 

[Grim]

I don't know much about injectors but could one or more be leaking? Maybe test them?

 

[SabotageR1]

I'm not that verse with pwc's but I used to be really good with repairing motorcycles. I had a client who had a similar issue and it turned out to be electrical. He had a bad ground. Once we solved the ground issue the bike ran great.

 

[Rockenrog]

Are you getting a maint light when it surges? If so, you may need to find someone that can pull the codes. Are you able to monitor fuel pressure while it surges?

No when I bought the new rectifier the light went away. Still only getting 100 psi on fuel. Quantum even sent me another pump for free. Still 100psi. I know this is the problem. Thoughts?

 

[Rockenrog]

Ok going to order a new fuel regulator. Any other thoughts on this?

 

[WaarrEagle]

Your earlier post about seeing 65 PSI with key on and engine off points to a regulator problem. Not too expensive or hard to replace so thats what I would do next.

 

[Rockenrog]

Your earlier post about seeing 65 PSI with key on and engine off points to a regulator problem. Not too expensive or hard to replace so thats what I would do next.

Yeah I have the fuel doing well now. But I have a low rpm miss it stumbles ba ba babababa. Like that until I hit 4700 rpm then it smooths out till wide open throttle then I feel it serge a little. Any thoughts?

 

[Rockenrog]

Your earlier post about seeing 65 PSI with key on and engine off points to a regulator problem. Not too expensive or hard to replace so thats what I would do next.

Any thoughts on my new problem?

 

[WaarrEagle]

Any thoughts on my new problem?

Are you sure you fully resolved the fuel pressure issue? Can you monitor fuel pressure while it is happening? Steady fuel pressure confirms performance of the air + fuel system so that is why it is so important in DI troubleshooting. Are you getting a Maint light?

 

[mikidymac]

About 4500 rpm is when the RAVE valves open. I would check them and make sure they are clean and functioning properly.