• This site contains eBay affiliate links for which Sea-Doo Forum may be compensated.

01' GTX DI Cranks but won't fire.

Status
Not open for further replies.

lmorefield41

New Member
I have a 2001 GTX DI that cranks and does not start. I've checked for fuel, spark, and combustion, good on all 3. The pressure was 130/131lbs for cylinder 1 and 2. I sprayed stater fluid into the intake and it starts up for a short amount of time, then dies. I tried revving the throttle after spraying the starting fluid in the intake and it revs, then dies again. It won't start unless I'm spraying starter fluid, which makes no sense because the fuel is being delivered and the pressure is good. I don't think there are any issues with the pump, it hums nicely when I put the key on. I also get the 2 beeps when putting on the key. Any help is greatly appreciated. I'm new to the forum. I received the jet ski from my uncle, he hasn't rode it in 2 years. It was garage kept and he let me have it as it was collecting dust. Had no issues prior 2 years ago when he rode it last. He can't ride anymore due to a bad hip. I put fresh gas in there, changed the battery, changed the plugs, and now I'm looking for help as I'm at wits end regarding what to do next. Thanks in advance!
 
Sounds like fuel injectors are plugged up. But check your fuses and get a simple test light, unplug an injector wire and hook up the test light to both pins (you may need to use a paperclip to get inside the connector) Crank the ski and see if it lights up. If it does, for sure fuel injectors, if not, then you have a wiring or computer issue. Check the crank sensor as well.

Also, the DI's need 108 PSI to run. Just because the pump runs, does not mean it has enough pressure to start. Do a pressure test and report back.
 
The DI's are very difficult if not impossible to diagnose without the proper test equipment. First thing with these machines is you need to make sure there are no maintenance warnings on the info center when your trying to start it. Also, make sure you have a good battery & that its producing over 10V while cranking.

The part of these machines that is not monitored by the MPEM is the fuel injection system. When you say its injecting fuel, I assume you either have the rail removed or its injecting with the spark plugs out?

The system has to be working with the correct air & fuel pressure to overcome the compression building in the cylinders. if either pressure is off by too much, its not going to inject in real time.

To test these systems you need to be able to test the fuel pressure & if that is out of spec, you may need to test the air pressure. to test the fuel pressure you need to purchase or make tester with a tee that will connect to the 5/16" snap connectors on the starboard side of the hull. its has to be in line, & not dead headed on the pump.

How are you verifying your fuel is being injected? your compression seems fine, but out of curiosity, are you holding the throttle wide open while testing? or leaving it at idle.

68RT
 
Sounds like fuel injectors are plugged up. But check your fuses and get a simple test light, unplug an injector wire and hook up the test light to both pins (you may need to use a paperclip to get inside the connector) Crank the ski and see if it lights up. If it does, for sure fuel injectors, if not, then you have a wiring or computer issue. Check the crank sensor as well.

Also, the DI's need 108 PSI to run. Just because the pump runs, does not mean it has enough pressure to start. Do a pressure test and report back.

Will do!

The DI's are very difficult if not impossible to diagnose without the proper test equipment. First thing with these machines is you need to make sure there are no maintenance warnings on the info center when your trying to start it. Also, make sure you have a good battery & that its producing over 10V while cranking.

The part of these machines that is not monitored by the MPEM is the fuel injection system. When you say its injecting fuel, I assume you either have the rail removed or its injecting with the spark plugs out?

The system has to be working with the correct air & fuel pressure to overcome the compression building in the cylinders. if either pressure is off by too much, its not going to inject in real time.

To test these systems you need to be able to test the fuel pressure & if that is out of spec, you may need to test the air pressure. to test the fuel pressure you need to purchase or make tester with a tee that will connect to the 5/16" snap connectors on the starboard side of the hull. its has to be in line, & not dead headed on the pump.

How are you verifying your fuel is being injected? your compression seems fine, but out of curiosity, are you holding the throttle wide open while testing? or leaving it at idle.

68RT

I'm going to rent the tools right now to test the fuel pressure. I bought and installed a brand new battery, I'm getting right around 10.5-10.7v while cranking. The battery is at around 12.7v when doing nothing. There are no maintenance warnings that are showing up. And to verify the fuel, it appeared to be injecting into the cylinders with the plugs out. I'm understanding now that this may not be enough pressure.

I will test out from everything that you guys have mentioned above then I will report back with what I find.

Thanks for all the help!
 
When you test the fuel pressure some varying things can happen.

First, you need to make sure there is no air pressure in the rail. remove the nylon braided air line off the rear of the rail. you can put it right back together after. the retaining screw should have at least blue thread locker, but should have a drop of red.

Then while watching the gage, install the lanyard. The pump will run for 2 seconds. you should see about 28-29 PSI, then sit & hold at 25-27psi. no matter how many times you install the key, this should keep happening. the pressure should not bleed out right away. It should hold for at least 20-30 minutes, I have seen them hold 50% or more for 12+ hours.

If that test good, now you need to spin the engine over as if you are trying to start it. Unlike the compression test, Do not touch the throttle, leave it in the idle position.

The fuel pressure should very quickly climb to 105+ essentially 80 psi more than you had at lanyard key install. however, this time the needle is going to be bouncing with the compression strokes of the air pump. Take note of the avg needle position. Thats what your looking for.
 
The the air side can be tested as well, in fact you can do a work around without the special pressure tester. But, you do need compressed shop air regulated around 85-90 psi. You just need to remove that same air line, but this time from the compressor side. carefully remove the o-ring from the line so you do not damage it. then clamp a 3/8 air line to that hose & connect it to you compressed air source. You need a way to regulate the air pressure & slowly raise the pressure. When you hit 78+/- PSI the regular will release the extra pressure out the back of the rail. you can hear it happen. just go slow, do not blast 140 PSI into the rail!

If this test passes & you can maintain that pressure. keep the air at that pressure & install the lanyard key. you should now see your target 105-107 fuel pressure. (without the bouncing needle) IF you do have the required pressure, you should be able to start the ski & run it as you have what is needed for pressures to fire. If your fuel pressure fails again, you have a fuel problem. then its going to be the fuel pressure regulator (not as likely at this point) or a fuel pump issue.

There is one more thing you can do to rule out the fuel regulator, but I don't want to dump to much info that might not be needed yet.

If the ski starts & runs with shop compressed air, you have an air pump problem. your can also put a gauge on the air pump & test it. should make 90 psi at cranking. Personally I like the first test better because its tests more things in one shot.

68RT
 
Last edited by a moderator:
Hey 68RT, a BRP factory trained mechanic friend said that he rarely sees a compressor problem, that it is most always the fuel pump, when the rail won't come up to the 107 psi.
Is that your experience, or can you offer different statistics?
 
I am just a hobbyist with a passion & I have worked on a limited amount of these machines so I could never give any statistic. But the air pumps are so simple in design that I would agree with you. Like you know, from your experience there is so much more that can go wrong on the fuel side.

I still think checking the air pump & pressure regulator is so easy that it seems worth doing before condemning a fuel pump for low pressure when its possible the air pump could be the problem. I would feel terrible telling another member their pump is shot from low pressure & then find out later it had to do with the air side.

One thing I did find interesting is the machines will start & run with lower air pressure. I had one of mine start & idle with only 50 psi of air & 77 lbs of fuel. It would seem the 27lb differential between the air/fuel is the really important part as far as starting goes anyway.

After studying these things, I think another easy backwards way to determine a fuel pump problem without any gauges would be to just disconnect the fuel return line, hook up a long length of 5/16" hose & put it in a bucket.
If zero fuel comes out while cranking & the pump is confirmed to be running at the time, the problem has more than likely just been found. :)

But, I still would want to see pressures as I am an complete information junkie...... ;)
 
Thanks for having such a passion and being so analytical and inquisitive, since we all benefit from it.

Your research is interesting since 50+77=127 which is 20 psi higher than the 107 psi usually needed. When I have observed fuel pumps going bad while riding with my fuel pressure gauge installed, the motor keeps running down to the mid 90's pressure then begins to stumble and finally die at about 90 to 93 psi. When pumps are dying like that, you can wait awhile and it will start up again and run, for awhile anyway.

I like your easy no gauge test to see what if any fuel returns from the rail to the tank (or bucket). This is certainly a quick test for the vast majority of people that don't have a pressure gauge tool built up.
 
Sorry if I made my numbers confusing.

I had 50 psi of air in the rail which bumped the fuel by 50psi 27+50 equalling 77 PSI in the fuel rail. I used a regulator on the air side & messed with a good running machine to see what would happen.

What your saying in your tests makes perfect sense, in fact it really confirms the importance of the 27 psi differential between the air & fuel rails. In your case, assuming you where around the required 78-80psi air, the 90-93 PSI (fuel) would leave you with maybe 12-15 lbs, difference between them? that must be the breaking point.

When I dropped the air pressure to 50 psi, that dropped the fuel regulator level to 77 & it still ran. but it still had the 27 psi fuel/air differential. It would seem this lower air pressure was enough to inject the air/fuel mix into the cylinder & run/start on the trailer, but I'll bet it would fail miserably in the water. When I raised the air pressure back to 78-80 (while it was running) it immediately sounded better & smoother.
 
I was finally able to fabricate something that allows me to test the pressure in line. The problem that I'm running into is the battery is dying before I can get the PSI to max out. Each time it's died around 70 PSI. I feel like there's more to go. Is this a problem? How long should it take to get to 107-110 PSI? I did not get a chance to check the air yet, have been fooling around with the tool to check the fuel pressure.
 
How long are you cranking?

With a healthy battery, it should only take 2-3 seconds. if its not getting there in 5-10 seconds, its not going to happen. But if the battery is failing quickly, you really need to install a new battery. Hopefully you are not spinning it over with a battery charger hooked up. that can cause damage the MPEM & then you'll have even bigger problems.

What was your pressure in the first part of the test?
 
How long are you cranking?

With a healthy battery, it should only take 2-3 seconds. if its not getting there in 5-10 seconds, its not going to happen. But if the battery is failing quickly, you really need to install a new battery. Hopefully you are not spinning it over with a battery charger hooked up. that can cause damage the MPEM & then you'll have even bigger problems.

What was your pressure in the first part of the test?

It was taking roughly 20+ seconds to die out. The battery is brand new, I purchased it on Saturday. Had to add the acid in and all that fun stuff. Not cranking it with the charger hooked up. I've been taking it out of the ski to charge it. The thing with the psi is it keeps increasing, it get to 70 PSI then it stops as the batter dies out. But it takes about 20 seconds to do so. When I opened the line up, an enormous amount of pressure shot out. I'll take a picture of the setup tonight and post it on here to make sure I actually have it hooked up right. I'm used to the Schrader valve when testing fuel pressure, so I may have it connected wrong. I'll take a video of me cranking and the PSI going up as well. I hate to keep killing the battery. It's warrantied so....
 
OK, good info.

The pressure should take seconds. if its not there in 10, its never going to happen. The gauge just needs to be in line so everything is still hooked up, not dead headed. however, if you dead headed the pump & only had 70 psi, your pump is pooched. That being said, don't try that, a healthy pump is strong enough to blow apart you connections. 150+ psi with no problems.

It will spray fuel all over the place with only 10 psi in it, so thats pretty normal. I have a fuel injection pulse tool that I use to bleed out the air & fuel pressures before I disconnect. The candoo can also do that, but not a cheap investment.

I think you should be able to cheat by pulling the fuel pump fuse & cranking it. it should bleed out the pressure through the injectors. yes, more fuel in the cylinders which isn't helping things much, so choose your poison. ;)

I hate to keep asking, but what was your pressure when you first put the key on? This is important to see if your regulator is working. If there is still air pressure in the rail that needs to be released first. Normally the air pressure will leak out on its own within a couple hours at most.


EDIT: I'll digress on the fuse pulling part. the fuel isn't going to bleed out unless you have the airline disconnected & spark plugs out too.

Really no need to keep pulling the gauge tho. that can stay in place & check other things. Get back with how the gauge is connected & your initial PSI. then we can go from there. pictures wouldn't hurt either.
 
Last edited by a moderator:
OK, so the links below are to my setup, what happens when I turn the key on, what happens when I try to start it, then a video of my fuel rail.

Setup:
https://www.youtube.com/watch?v=92B6Lqkoklo&index=2&list=UU1B9JKWqPik8BWpO9hrr9cQ

Inserting the Key:
https://www.youtube.com/watch?v=xNyEg06YQbE&list=UU1B9JKWqPik8BWpO9hrr9cQ&index=1

Trying to Start/Fuel Pressure test:
https://www.youtube.com/watch?v=lJJDCTK2ON0&list=UU1B9JKWqPik8BWpO9hrr9cQ&index=3

Fuel Rail:
https://www.youtube.com/watch?v=AdJCwwtCq6Q&index=4&list=UU1B9JKWqPik8BWpO9hrr9cQ

From what I read above, it looks like I'm either running this test incorrectly, or the fuel pump is toast. Thanks again in advance for all the help.
 
When you test the fuel pressure some varying things can happen.

First, you need to make sure there is no air pressure in the rail. remove the nylon braided air line off the rear of the rail. you can put it right back together after. the retaining screw should have at least blue thread locker, but should have a drop of red.

Then while watching the gage, install the lanyard. The pump will run for 2 seconds. you should see about 28-29 PSI, then sit & hold at 25-27psi. no matter how many times you install the key, this should keep happening. the pressure should not bleed out right away. It should hold for at least 20-30 minutes, I have seen them hold 50% or more for 12+ hours.

If that test good, now you need to spin the engine over as if you are trying to start it. Unlike the compression test, Do not touch the throttle, leave it in the idle position.

The fuel pressure should very quickly climb to 105+ essentially 80 psi more than you had at lanyard key install. however, this time the needle is going to be bouncing with the compression strokes of the air pump. Take note of the avg needle position. Thats what your looking for.

This is the post that I was referring to above.
 
Great job with the videos, very helpful.

I have to say though, I was feeling terrible for your starter & battery. ;)

Anyway, you have a definite fuel issue. when you put the key on, it should jump to 27+ psi in less than 2 seconds. I would test one more thing before pulling the pump though.

disconnect the return fuel line from the rail, & see if you can redirect that line into a can or bucket by adding a length of hose to it. Put the key on a bunch of times without starting it like in your video. if you get less than 27 lbs on the gauge & nothing out of the return line at the same time you can hear your pump run, your pump is definitely bad.

From what I see in the video tho, its looks like a bad fuel pump, or completely plugged internal filters. maybe even both?
 
Great job with the videos, very helpful.

I have to say though, I was feeling terrible for your starter & battery. ;)

Anyway, you have a definite fuel issue. when you put the key on, it should jump to 27+ psi in less than 2 seconds. I would test one more thing before pulling the pump though.

disconnect the return fuel line from the rail, & see if you can redirect that line into a can or bucket by adding a length of hose to it. Put the key on a bunch of times without starting it like in your video. if you get less than 27 lbs on the gauge & nothing out of the return line at the same time you can hear your pump run, your pump is definitely bad.

From what I see in the video tho, its looks like a bad fuel pump, or completely plugged internal filters. maybe even both?

I did what you said above, I got no pressure or no gas coming from the return line. I ordered a pump, however, it's way less than what I expected. This is the link, can you tell me what you think of this instead of the $900 OEM pump from the dealer? http://www.ebay.com/itm/290945806151?_trksid=p2060778.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT I looked at the reviews for this pump and looked at the problems the people had and this pump seemed to fix the problem. Any advice or suggestions on this?
 
This site contains eBay affiliate links for which Sea-Doo Forum may be compensated.
DooWacka, is probably the guys to ask when it comes to aftermarket pumps. He has a great right up on the swap out.

It seems pretty obvious now the pump is shot, but You might still want to pull out the baffle & make sure the internal filters are not plugged up tight. Its possible. however if they are plugged ,the pump might have failed because of it. still worth checking & it has to come apart anyway.
 
Thanks! I appreciate the feedback! It's warrantied for 1 year, and I can return it if I don't use it. I'll also try what you mentioned above. Is it normal for the fuel pump to hum with turning on the key even if it's not working?
 
[MENTION=57696]68ragtop[/MENTION], I have some new info regarding my current pump. I went out and hit the gas tank carefully with a hammer to try and shake up the pump (did this on a car tank before and got a few months out of the fuel pump before it went all the way out) and then put the key in, the pump not only sounded different, but I got roughly 15 psi out of just putting the key in. I then tried to start and it climbed to 80 psi rather quickly it still didn't start, however that should be a sure sign that the pump is absolutely bad right? Also, the pressure relieve valve on the fuel pressure tester never let anything but air out when pushed except air before, this time it let fuel out. I'm going to let the battery charge up overnight. Go back out in the morning and try to dig deeper. I'll do the test with return line as well tomorrow. If I can get it started I'm going to remove the pump, clean the internal filters and give it another shot.
 
The problem is the fuel injectors inject into the air rail. When the air rail is working correctly, it will be around 80 PSI in there even cranking, so when you see 80 PSI on the fuel pump its essentially like having no fuel pressure at all. 80 psi on both side of the injector, so no fuel comes out.

Air in the fuel line is really no big deal. pressure is pressure wether its air or fuel. The air of coarse will compress where the fuel will not, so I am not saying they are they same that way, just saying the air isn't going to effect the pressure reading your seeing on the gauge. the bleed off valves on test gauges are great for releasing pressure so you can remove them, but really don't serve any other purpose.
 
Last edited by a moderator:
It's alive!!

It seemed to start slow (cranked longer than it should) & I could hear a bog I think? How are your fuel pressures now? I am guessing they climb much faster than before & must get over 95 psi, but drop lower when you blip the throttle?

A healthy fuel pressure will actually rise a bit from idle when revved. I have a feeling yours is dropping a little? With it running, its a little tougher to read pressures as the fluctuation of air pressure in the rail will make the needle vibrate a bit. Not terrible, but noticeable.

How bad where the filters, did you replace them? they are available at most chain auto part stores. Just not by application.

The sad thing is, I have a feeling it may have been run for a while like this so if now your filters are completely clean, either your inline filter is plugged up, or the pump is bad. I cut apart an inline filter I replaced after finding some intake filters completely plugged up. The inline filter was really in good shape. They are so large, I think they are designed to outlast the life of the ski......

I think 2001 had the double oetiker clamps on the filter, so you could remove it & test that if you wanted too as well.

I sense some light at the end of the tunnel however......
 
Status
Not open for further replies.
Back
Top