GTX DI Will Not Start

[WaarrEagle]

My 2000 GTX DI will currently not start, ~225 hrs on the motor. For years it has idled a bit rough but would not die. Last year it was going into limp mode and I took it to a local mechanic. He replaced the regulator, gave it back, and the ski was still not running correctly. I took it back, he replaced another part (something cheap, ~$30, but not documented on receipt), and it ran better but even then I recall the idle was not perfect.

This season it ran okay for several weeks but recently it would die at idle. If you got on the gas it would run great, ran it up to ~6700 RPM without issue at ~55 MPH. When returning to idle it would slow to 1350, then 1250 and die. It is now at the point where it will not start at all, even with throttle. It turns over, catches quickly and runs for a brief moment, then stops and you hear the 2 puffs of air or whatever when you turn it off. I had the battery checked at the auto parts store... it tested fine. I used jumper cables to tie into a much larger boat battery thinking perhaps the voltage was dropping, but got the same result.

I am pretty tech savvy but have no tools currently for the ski. Should I be checking voltage, fuel pressure, compression, spark plugs, etc or just take it to the shop? I see lots of folks with trouble on these old DI's but would like to try a couple things before losing several weeks of summer waiting for service at the shop.

Edit: Not my video but it acts very similar to this:

The poster said the air injectors were his problem, but did not elaborate on what exactly needed replaced.

 

[jhjesse]

I would do a compression test first, especially with 225 hours. Needs to be 130 to 140psi. Anything 120psi or lower and it is in need of a rebuild.
What color are the plugs? Maybe black and sooty? If they are then you need to clean/replace the injectors.
If no maint lights the it is probably fuel related. Fuel pressure is probably low due to clogged filters. I would pull the pump clean it really good and replace the internal fuel filters as well as the external fuel filter.
I usually cut the expensive canister off and replace with a metal inline filter. Wix 33095.
Internal filters are Airtex FS220 and FS242

 

[WaarrEagle]

Update: I took the ski to a local shop and their front desk clerk just called to tell me it needs a "new motor". Estimate is $2500-$3000. The clerk was unable to explain any further, but I will be speaking with someone more knowledgeable tomorrow. What should I be asking in terms of diagnosis? Compression is obvious but what else should I question to make sure it truly needs a new motor?

 

[jhjesse]

Compression mainly. Ask to see the numbers. If it is actually bad, get the ski back and do it yourself for half or less cost.
The good people on this forum will help you through it.
Also ask what the fuel pressure number was when they checked it? (Doubt it was checked)

 

[WaarrEagle]

Talked to the shop owner. 150 in the back cylinder but 70 in the front. He did not go further and check fuel pressure after finding compression that low. Given the point in the season, I am just going to throw it in the garage and maybe make it a winter project.

 

[mikidymac]

It can’t be 150 as a DI is 130-140 on a perfect engine but either way the 70 means the engine is toasted.